Spores on leaf Black and White Stock Photos & Images - Page 3

The bright green backlit leaves of a hard fern, Pelleae Calomelanos, on a hill in the ridges of the Vredefort Dome, South Africa Stock Photo

RF2R71XH6–The bright green backlit leaves of a hard fern, Pelleae Calomelanos, on a hill in the ridges of the Vredefort Dome, South Africa

Greenery bring happiness. Fern growing outdoor. Fern bed in woods. Green fern tree in spring or summer. Fern leaves on natural background. Stock Photo

RF2A184NH–Greenery bring happiness. Fern growing outdoor. Fern bed in woods. Green fern tree in spring or summer. Fern leaves on natural background.

Image of spores and cysts on a rose leaf, vintage line drawing or engraving illustration. Stock Vector

RF2BTH204–Image of spores and cysts on a rose leaf, vintage line drawing or engraving illustration.

. [Scientific lectures]. of conida of the OidiumMonilioides; 6, portion of grass leaf with samespecies of blight, the spores being the self-same beads and egg-shaped bodies, whencethe generic name, but careful observationwill show us that this ig not its perfect con-dition; and when later in autumn thesethreads become more compact, and are sur-mounted on their horizontal surfaces byshining black capsules, or perithecia, each ofwhich is filled with elegant eUiptical andelongated cells, and each in turn contain-ing several spores, we shall find in Erisypliethat we have arrived at the conclusion Stock Photo

RM2AG36W7–. [Scientific lectures]. of conida of the OidiumMonilioides; 6, portion of grass leaf with samespecies of blight, the spores being the self-same beads and egg-shaped bodies, whencethe generic name, but careful observationwill show us that this ig not its perfect con-dition; and when later in autumn thesethreads become more compact, and are sur-mounted on their horizontal surfaces byshining black capsules, or perithecia, each ofwhich is filled with elegant eUiptical andelongated cells, and each in turn contain-ing several spores, we shall find in Erisypliethat we have arrived at the conclusion

Close up nature portrait of puffball fungi, Selsdon Wood, England, United Kingdom, Europe Stock Photo

RM2A8YCD8–Close up nature portrait of puffball fungi, Selsdon Wood, England, United Kingdom, Europe

. Manual of tree diseases . Trees. MAPLE DISEASES 229 fungus. The spores from these structiu'es are disseminated by the rain. It is to be expected that perithecia with ascospores are formed in the leaves on the ground during the winter. The twigs have not been found affected. This disease is similar to the leaf- and twig-blight of sycamores described on page 333. The control measures are the same for both of these diseases. Canker Caused by Nectria cinnabarina Fries Maples are commonly affected by this canker. Other deciduous trees may also be attacked by this disease but it never assumes grea Stock Photo

RMPG14JA–. Manual of tree diseases . Trees. MAPLE DISEASES 229 fungus. The spores from these structiu'es are disseminated by the rain. It is to be expected that perithecia with ascospores are formed in the leaves on the ground during the winter. The twigs have not been found affected. This disease is similar to the leaf- and twig-blight of sycamores described on page 333. The control measures are the same for both of these diseases. Canker Caused by Nectria cinnabarina Fries Maples are commonly affected by this canker. Other deciduous trees may also be attacked by this disease but it never assumes grea

RMRDX0Y9–. Fungi, ascomycetes, ustilaginales, uredinales. Fungi. 186 HEMIBASIDIOMYCETES [CH. fields. As a rule the conidia are of the same oblong form as the basidio- spores, but, in the genus Tilletia and some of its allies, they may be stout or sickle-shaped, whereas the basidiospores are long and narrow. In Entyloma the brand-spores are capable of germination on the tissues of the host leaf, where they give rise to hyphae which penetrate through the stomata and form basidia from which basidiospores are produced. During their development the cells of the basidium, the basidiospores, or the conidia bu

. Botany for agricultural students . Botany. POTATO BLIGHT (PHYTOPHTHORA INFESTANS) 357 scattered about like spores. When the conidia germinate, instead of producing hyphae they produce zoospores, which, after swimming about for a few minutes, lose their cilia and begin to produce new hyphae. If favorably located, the new hyphae find entrance to a leaf through its stomata and start the disease anew. The oogonia and antheridia resemble those of Saprolegnia, but are produced on short hyphae within the tissues of the host. The oospore has a heavy wall and is not liberated until the tissues of the Stock Photo

RMPG4B3W–. Botany for agricultural students . Botany. POTATO BLIGHT (PHYTOPHTHORA INFESTANS) 357 scattered about like spores. When the conidia germinate, instead of producing hyphae they produce zoospores, which, after swimming about for a few minutes, lose their cilia and begin to produce new hyphae. If favorably located, the new hyphae find entrance to a leaf through its stomata and start the disease anew. The oogonia and antheridia resemble those of Saprolegnia, but are produced on short hyphae within the tissues of the host. The oospore has a heavy wall and is not liberated until the tissues of the

RMRDFDYW–. Manual of tree diseases . Trees. MAPLE DISEASES 229 fungus. The spores from these structiu'es are disseminated by the rain. It is to be expected that perithecia with ascospores are formed in the leaves on the ground during the winter. The twigs have not been found affected. This disease is similar to the leaf- and twig-blight of sycamores described on page 333. The control measures are the same for both of these diseases. Canker Caused by Nectria cinnabarina Fries Maples are commonly affected by this canker. Other deciduous trees may also be attacked by this disease but it never assumes grea

. A manual of veterinary hygiene. Veterinary hygiene. 164 VETEKINAEY HYGIENE and spots. The colour is due to the spores of the fungus, which can be shaken off the leaf and are found to be of a rusty appearance. These spores, known as uredosjyores, are produced by the growth of a mycelium in the substance of the leaf, and should they get detached from the plant by air currents or otherwise, and fall on members of the grass tribe, these become infected with rust. As the summer advances, the mycelium on the leaf which has been producing the orange-red uredospores, now. Fig. 27-—Rust and Mildew (F Stock Photo

RMPG0E21–. A manual of veterinary hygiene. Veterinary hygiene. 164 VETEKINAEY HYGIENE and spots. The colour is due to the spores of the fungus, which can be shaken off the leaf and are found to be of a rusty appearance. These spores, known as uredosjyores, are produced by the growth of a mycelium in the substance of the leaf, and should they get detached from the plant by air currents or otherwise, and fall on members of the grass tribe, these become infected with rust. As the summer advances, the mycelium on the leaf which has been producing the orange-red uredospores, now. Fig. 27-—Rust and Mildew (F

. Microbes, ferments and moulds . Bacteria; Fungi; Fermentation. 48 MICROBES, FERMENTS, AND MOULDS. wasp, because it is attacked during its lifetime by a fungus which it carries about for some time, and which finally causes its death: this is Torrubia spherocephala (Tulasne). Isaria sphingum, another m Fig. 21.—Two filaments of Sapro- legnia containing spores (grejitly magnified).. Fig. 22.—Oogonium of Saprolegnia surrounded by Antheridia (much magnified). species of the same genus, has been observed on the back of a butterfly, which was poised upon a leaf as if alive, and which was probably k Stock Photo

RMRDJ5B9–. Microbes, ferments and moulds . Bacteria; Fungi; Fermentation. 48 MICROBES, FERMENTS, AND MOULDS. wasp, because it is attacked during its lifetime by a fungus which it carries about for some time, and which finally causes its death: this is Torrubia spherocephala (Tulasne). Isaria sphingum, another m Fig. 21.—Two filaments of Sapro- legnia containing spores (grejitly magnified).. Fig. 22.—Oogonium of Saprolegnia surrounded by Antheridia (much magnified). species of the same genus, has been observed on the back of a butterfly, which was poised upon a leaf as if alive, and which was probably k

. A text-book of mycology and plant pathology . Plant diseases; Fungi in agriculture; Plant diseases; Fungi. 190 MYCOLOGY upright and divided transversely into four cells, each of which cuts off abasidiospore. These basidiospores are blown to the leaves, twigs, or fruits of the barberry where a mycelium is formed. Later pycnia (spermogonia) appear on the upper side of its leaf. These are accom- panied by round, fringed depressions, the cluster cups or aecia, which appear in the spring on the lower side of the leaves. The aeciospores are arranged in chains. These spring spores, asciospores, are Stock Photo

RMPG4529–. A text-book of mycology and plant pathology . Plant diseases; Fungi in agriculture; Plant diseases; Fungi. 190 MYCOLOGY upright and divided transversely into four cells, each of which cuts off abasidiospore. These basidiospores are blown to the leaves, twigs, or fruits of the barberry where a mycelium is formed. Later pycnia (spermogonia) appear on the upper side of its leaf. These are accom- panied by round, fringed depressions, the cluster cups or aecia, which appear in the spring on the lower side of the leaves. The aeciospores are arranged in chains. These spring spores, asciospores, are

RMRDE2F6–. A text-book of mycology and plant pathology . Plant diseases; Fungi in agriculture; Plant diseases; Fungi. 190 MYCOLOGY upright and divided transversely into four cells, each of which cuts off abasidiospore. These basidiospores are blown to the leaves, twigs, or fruits of the barberry where a mycelium is formed. Later pycnia (spermogonia) appear on the upper side of its leaf. These are accom- panied by round, fringed depressions, the cluster cups or aecia, which appear in the spring on the lower side of the leaves. The aeciospores are arranged in chains. These spring spores, asciospores, are

. Botany for agricultural students . Botany. 440 PTERIDOPHYTES (FERN PLANTS) The strobilus, therefore, arose as a result of differentiating the leaves in function and aggregating the sporophylls. Differing in function, sporophylls and vegetative leaves would come to differ in form. One can see considerable advantage in this to the plant. It permits a large amount of leaf tissue to be devoted entirely to the manufacture of food, while the sporophylls, since they are not depended upon for food, can be much crowded, and as a result many spores can be produced on a small region. In scattering the Stock Photo

RMPG4A3J–. Botany for agricultural students . Botany. 440 PTERIDOPHYTES (FERN PLANTS) The strobilus, therefore, arose as a result of differentiating the leaves in function and aggregating the sporophylls. Differing in function, sporophylls and vegetative leaves would come to differ in form. One can see considerable advantage in this to the plant. It permits a large amount of leaf tissue to be devoted entirely to the manufacture of food, while the sporophylls, since they are not depended upon for food, can be much crowded, and as a result many spores can be produced on a small region. In scattering the

. Text-book of botany, morphological and physiological. Botany. 1J2, MORPHOLOGY OF MEMBERS. transformed into the sporogonium, a structure without leaves, roots, or branches, the sole function of which is the production of spores. A new Moss-plant is, on the contrary, constituted by the production of a leaf-bearing shoot from a branch of the alga-like Protonema, which branches, strikes root (by root- hairs), and is independently nourished. The shoot first produced, from which are developed the rest, is termed the Primary Shoot; it is often more strongly developed than its lateral shoots, as in Stock Photo

RMRPXR7X–. Text-book of botany, morphological and physiological. Botany. 1J2, MORPHOLOGY OF MEMBERS. transformed into the sporogonium, a structure without leaves, roots, or branches, the sole function of which is the production of spores. A new Moss-plant is, on the contrary, constituted by the production of a leaf-bearing shoot from a branch of the alga-like Protonema, which branches, strikes root (by root- hairs), and is independently nourished. The shoot first produced, from which are developed the rest, is termed the Primary Shoot; it is often more strongly developed than its lateral shoots, as in

. A manual of weeds : with descriptions of all the most pernicious and troublesome plants in the United States and Canada, their habits of growth and distribution, with methods of control . Weeds. DESCRIPTIVE LIST AND MEANS OF CONTROL COMMON BRAKE, OR BRACKEN Ptiris aquilina, L. Other English names: Eagle Fern, Upland Fern, Turkey-foot Brake. Native. Perennial. Propagates by spores and by rootstocks. Season of leaf-production: Early spring until autumn frosts. - Fruiting fronds: Ripe in August. Range: Throughout the world. In this country most troublesome on the Pacific Coast. Habitat: Upland Stock Photo

RMPG23R2–. A manual of weeds : with descriptions of all the most pernicious and troublesome plants in the United States and Canada, their habits of growth and distribution, with methods of control . Weeds. DESCRIPTIVE LIST AND MEANS OF CONTROL COMMON BRAKE, OR BRACKEN Ptiris aquilina, L. Other English names: Eagle Fern, Upland Fern, Turkey-foot Brake. Native. Perennial. Propagates by spores and by rootstocks. Season of leaf-production: Early spring until autumn frosts. - Fruiting fronds: Ripe in August. Range: Throughout the world. In this country most troublesome on the Pacific Coast. Habitat: Upland

. Elementary botany. Botany. Fig. 24V Base of leaf of isoetes, showing sporangium with macrospores. (Isoetes en- gelmannii.). Fig. 250. Section of plant of Isoetes engelmanii, showing cup- shaped stem, and longitudinal sections of the sporan- gia in the thickened bases of the leaves. ure from the other portions of the leaf. This is a sporangiuvi. Beside the spores on the inside of the sporangium, there are strands of sterile tissue which extend across the cavity. This is peculiar to isoetes of all the members of the class of plants to which the ferns belong, but it will be remembered that ster Stock Photo

RMRDW83A–. Elementary botany. Botany. Fig. 24V Base of leaf of isoetes, showing sporangium with macrospores. (Isoetes en- gelmannii.). Fig. 250. Section of plant of Isoetes engelmanii, showing cup- shaped stem, and longitudinal sections of the sporan- gia in the thickened bases of the leaves. ure from the other portions of the leaf. This is a sporangiuvi. Beside the spores on the inside of the sporangium, there are strands of sterile tissue which extend across the cavity. This is peculiar to isoetes of all the members of the class of plants to which the ferns belong, but it will be remembered that ster

. Minnesota plant diseases. Plant diseases. Minnesota Plant Diseases. 389 The fungus threads, which are found in the swollen parts of the host plant and which cause the stimulation, whereby the increase of growth or swelling of the stem takes place, form their winter rust-spores inside of the cells of the epidermis of. Fig. 206.—Sunflower rust. Winter and summer spore clusters on the leaf of <l sunflower. Original. the host. This epidermis is much altered on account of the action of the fungus. Its cells have thin, instead of thick, outer walls, and are much increased in size. These spores Stock Photo

RMPG4EHE–. Minnesota plant diseases. Plant diseases. Minnesota Plant Diseases. 389 The fungus threads, which are found in the swollen parts of the host plant and which cause the stimulation, whereby the increase of growth or swelling of the stem takes place, form their winter rust-spores inside of the cells of the epidermis of. Fig. 206.—Sunflower rust. Winter and summer spore clusters on the leaf of <l sunflower. Original. the host. This epidermis is much altered on account of the action of the fungus. Its cells have thin, instead of thick, outer walls, and are much increased in size. These spores

RMRDCY6Y–. Botany for agricultural students . Botany. 440 PTERIDOPHYTES (FERN PLANTS) The strobilus, therefore, arose as a result of differentiating the leaves in function and aggregating the sporophylls. Differing in function, sporophylls and vegetative leaves would come to differ in form. One can see considerable advantage in this to the plant. It permits a large amount of leaf tissue to be devoted entirely to the manufacture of food, while the sporophylls, since they are not depended upon for food, can be much crowded, and as a result many spores can be produced on a small region. In scattering the

RMPG4AR8–. Botany for agricultural students . Botany. 398 THALLOPHYTES teleutospore produces a promycelium bearing the basidiospores, often called sporidia, as shown in Figure 355. Thus the teleuto- spore occupies the same position in the life history of Rusts as the brand spore occupies in the life history of Smuts. The basidio spores are scattered by the wind, and in regions where Barberry bushes grow, they come in contact with the leaves of the Barberry where they grow and produce mycelia in the leaf tissues. Upon the Barberry, the mycelia produce on the under surface of the leaf small cups called a

. Elementary botany. Botany. 342 ECOLOG V. divisions of the pinnse, are inrolled into little spherical masses which lie close on the side of the pinnae. If we unroll one of these pinnules we find that there are several fruit dots within protected by this roll. In fact when the spores are mature these. Fig. 446- Sensitive fern ; one fertile leaf nearly changed to vegetative leaf. pinnules open somewhat, so that the spores may be dissemi- nated. There is very little green color in these fertile leaves, and what green surface there is is very small compared with that of the broad expanse of the s Stock Photo

RMRDWE4M–. Elementary botany. Botany. 342 ECOLOG V. divisions of the pinnse, are inrolled into little spherical masses which lie close on the side of the pinnae. If we unroll one of these pinnules we find that there are several fruit dots within protected by this roll. In fact when the spores are mature these. Fig. 446- Sensitive fern ; one fertile leaf nearly changed to vegetative leaf. pinnules open somewhat, so that the spores may be dissemi- nated. There is very little green color in these fertile leaves, and what green surface there is is very small compared with that of the broad expanse of the s

. Comparative morphology and biology of the fungi, mycetozoa and bacteria . Plant morphology; Fungi; Myxomycetes; Bacteriology. Fig. 130. chrysomyxa Rhododendri in a leaf of Rh. hirsutttm. Vertical section through a teleutospore-layer. e—€ epidermis of the under surface of the leaf. Adjoining the spores is the tissue of the leaf traversed and distorted by mycelial filaments m of Chrysomyxa; a a row of teleutospores which have not yet germinated; / a similar row in which the uppermost teleutospore has formed a promycelium, and on this sterigmata and sporidia are beginning to be formed in basipe Stock Photo

RMPG1WTX–. Comparative morphology and biology of the fungi, mycetozoa and bacteria . Plant morphology; Fungi; Myxomycetes; Bacteriology. Fig. 130. chrysomyxa Rhododendri in a leaf of Rh. hirsutttm. Vertical section through a teleutospore-layer. e—€ epidermis of the under surface of the leaf. Adjoining the spores is the tissue of the leaf traversed and distorted by mycelial filaments m of Chrysomyxa; a a row of teleutospores which have not yet germinated; / a similar row in which the uppermost teleutospore has formed a promycelium, and on this sterigmata and sporidia are beginning to be formed in basipe

. Botany, with agricultural applications. Botany. POTATO BLIGHT (PHYTOPHTHORA INPESTANS) 357 scattered about like spores. When the conidia germinate, instead of producing hyphae they produce zoospores, which, after swimming about for a few minutes, lose their cilia and begin to produce new hyphae. If favorably located, the new hyphae find entrance to a leaf through its stomata and start the disease anew. The oogonja and antheridia resemble those of Saprolegnia, but are produced on short hyphae within the tissues of the host. The oospore has a heavy wall and is not liberated until the tissues o Stock Photo

RMRDWD5B–. Botany, with agricultural applications. Botany. POTATO BLIGHT (PHYTOPHTHORA INPESTANS) 357 scattered about like spores. When the conidia germinate, instead of producing hyphae they produce zoospores, which, after swimming about for a few minutes, lose their cilia and begin to produce new hyphae. If favorably located, the new hyphae find entrance to a leaf through its stomata and start the disease anew. The oogonja and antheridia resemble those of Saprolegnia, but are produced on short hyphae within the tissues of the host. The oospore has a heavy wall and is not liberated until the tissues o

. Plant studies; an elementary botany. Botany. 2Y2 PLANT STUDIES fiiKilly deadened spots on the leaves, where the tissues have been killed. From this internal mycelium numerous sporojihores arise, coming to the surface of tlie host and securing the scattering of their spores, which fall u])on other leaves and germinate, the new niycelia pene- trating among the tissues and begin- ning their ravages. The sporophores, af- ter rising above the surface of the leaf, branch freely; and many of them risiiig near together, they form little velvety patches on the surface, suggesting the name " down Stock Photo

RMPG3D31–. Plant studies; an elementary botany. Botany. 2Y2 PLANT STUDIES fiiKilly deadened spots on the leaves, where the tissues have been killed. From this internal mycelium numerous sporojihores arise, coming to the surface of tlie host and securing the scattering of their spores, which fall u])on other leaves and germinate, the new niycelia pene- trating among the tissues and begin- ning their ravages. The sporophores, af- ter rising above the surface of the leaf, branch freely; and many of them risiiig near together, they form little velvety patches on the surface, suggesting the name " down

. Elementary botany. Botany. 342 ECOLOG V. divisions of the pinnje, are inrolled into little spherical masses which lie close on the side of the pinnae. If we unroll one of these pinnules we find that there are several fruit dots within protected by this roll. In fact when the spores are mature these. Fig. 446. Sensitive fern ; one fertile leaf nearly changed to vegetative leaf. pinnules open somewhat, so that the spores may be dissemi- nated. There is very little green color in these fertile leaes, and what green surface there is is very small compared ^•ith that of the broad expanse of the Stock Photo

RMRE1N20–. Elementary botany. Botany. 342 ECOLOG V. divisions of the pinnje, are inrolled into little spherical masses which lie close on the side of the pinnae. If we unroll one of these pinnules we find that there are several fruit dots within protected by this roll. In fact when the spores are mature these. Fig. 446. Sensitive fern ; one fertile leaf nearly changed to vegetative leaf. pinnules open somewhat, so that the spores may be dissemi- nated. There is very little green color in these fertile leaes, and what green surface there is is very small compared ^•ith that of the broad expanse of the

. The fungal diseases of the common larch . Larches. 174 LEAF AND SEEDLING DISEASES to live till the spring and then to send out a small germ tube of limited growth, called the promycelium, and this bears a few, generally four, very small spores, which are known as sporidia. The sporidia are very light, and being lifted by the wind settle on the leaves of neighbouring plants. But, though they may germinate, they inevitably perish imless they happen to come in contact with a plant. Please note that these images are extracted from scanned page images that may have been digitally enhanced for rea Stock Photo

RMPG4DMJ–. The fungal diseases of the common larch . Larches. 174 LEAF AND SEEDLING DISEASES to live till the spring and then to send out a small germ tube of limited growth, called the promycelium, and this bears a few, generally four, very small spores, which are known as sporidia. The sporidia are very light, and being lifted by the wind settle on the leaves of neighbouring plants. But, though they may germinate, they inevitably perish imless they happen to come in contact with a plant. Please note that these images are extracted from scanned page images that may have been digitally enhanced for rea

. College botany; structure, physiology and economics of plants. Botany. Fig. 126.—Albugo Candida showing the formation of the conidia spores just below the epider- mis of the host plant and also the antheridium and archegonium. swim for a few minutes m the moisture on the surface of the leaf, come to rest, lose their cilia and produce new hyphse which penetrate the leaf through the stomata. The oogonia and anthe- ridia are very similar to those of the Albugo. The late blight of the potato is in reality a mildew and is caused by a fungus (Phytophthora infestans). It is very similar to the grap Stock Photo

RMRE1N9Y–. College botany; structure, physiology and economics of plants. Botany. Fig. 126.—Albugo Candida showing the formation of the conidia spores just below the epider- mis of the host plant and also the antheridium and archegonium. swim for a few minutes m the moisture on the surface of the leaf, come to rest, lose their cilia and produce new hyphse which penetrate the leaf through the stomata. The oogonia and anthe- ridia are very similar to those of the Albugo. The late blight of the potato is in reality a mildew and is caused by a fungus (Phytophthora infestans). It is very similar to the grap

. Botany for agricultural students . Botany. BLACK RUST OF GRAIN (PUCCINIA GRAMINIS) 399. Fig. 356. — Stage of the Wheat Rust on the Barberry bush, BcrherU vulgaris. Left, leaf of Barberry, showing the affected areas which are red- dish, much thickened, and contain many cup-like depressions; right, a very much enlarged section through the affected area of the leaf, showing one of the cups (c) with chains of aecidiospores (X 200). The very small spores at (p) are the spermatia or pycniospores.. Please note that these images are extracted from scanned page images that may have been digitally enh Stock Photo

RMPG4AR3–. Botany for agricultural students . Botany. BLACK RUST OF GRAIN (PUCCINIA GRAMINIS) 399. Fig. 356. — Stage of the Wheat Rust on the Barberry bush, BcrherU vulgaris. Left, leaf of Barberry, showing the affected areas which are red- dish, much thickened, and contain many cup-like depressions; right, a very much enlarged section through the affected area of the leaf, showing one of the cups (c) with chains of aecidiospores (X 200). The very small spores at (p) are the spermatia or pycniospores.. Please note that these images are extracted from scanned page images that may have been digitally enh

. Microbes, ferments and moulds . Bacteria; Fungi; Fermentation. 16 MICROBES, FERMENTS, AND MOULDS, of -wheat, but only upon the leaves of another plant, the barberry. Borne by the dew or by a drop of rain on to the young leaves of the barberry, the teleutospores germi- nate, and form reddish-brown patches which affect both sides of the leaf. On its lower surface the spores are smaller, and are termed spermata; their function is not thoroughly understood. The larger spores on the upper surface are called cecidiospores (Fig. 6), and with these we are more concerned, since. Fig. 6.—section of a Stock Photo

RMRDJ5F2–. Microbes, ferments and moulds . Bacteria; Fungi; Fermentation. 16 MICROBES, FERMENTS, AND MOULDS, of -wheat, but only upon the leaves of another plant, the barberry. Borne by the dew or by a drop of rain on to the young leaves of the barberry, the teleutospores germi- nate, and form reddish-brown patches which affect both sides of the leaf. On its lower surface the spores are smaller, and are termed spermata; their function is not thoroughly understood. The larger spores on the upper surface are called cecidiospores (Fig. 6), and with these we are more concerned, since. Fig. 6.—section of a

. Manual of fruit diseases . Fruit. STRAWBERRY DISEASES 423 amass themselves beneath the cuticle of either surface of the leaf, and from these masses conidiophores bearing conidia arise. These spores develop, are scattered and produce in- fections through- out the summer; with the advent of winter conidial formation ceases, but the mycelium remains alive in the leaves until the following spring. At this time a new crop of conidia develop, which begin the cycle anew by in- fecting again the strawberry plants. Should any of these spores per- chance fall on the common cinquefoil, the disease woul Stock Photo

RMPG3XYB–. Manual of fruit diseases . Fruit. STRAWBERRY DISEASES 423 amass themselves beneath the cuticle of either surface of the leaf, and from these masses conidiophores bearing conidia arise. These spores develop, are scattered and produce in- fections through- out the summer; with the advent of winter conidial formation ceases, but the mycelium remains alive in the leaves until the following spring. At this time a new crop of conidia develop, which begin the cycle anew by in- fecting again the strawberry plants. Should any of these spores per- chance fall on the common cinquefoil, the disease woul

. Botany, with agricultural applications. Botany. 440 PTERIDOPHYTES (FERN PLANTS) The strobilus, therefore, arose as a result of differentiating the leaves in function and aggregating the sporophylls. Differing in function, sporophylls and vegetative leaves would come to differ in form. One can see considerable advantage in this to the plant. It permits a large amount of leaf tissue to be devoted entirely to the manufacture of food, while the sporophylls, since they are not depended upon for food, can be much crowded, and as a result many spores can be produced on a small region. In scattering Stock Photo

RMRDWCM8–. Botany, with agricultural applications. Botany. 440 PTERIDOPHYTES (FERN PLANTS) The strobilus, therefore, arose as a result of differentiating the leaves in function and aggregating the sporophylls. Differing in function, sporophylls and vegetative leaves would come to differ in form. One can see considerable advantage in this to the plant. It permits a large amount of leaf tissue to be devoted entirely to the manufacture of food, while the sporophylls, since they are not depended upon for food, can be much crowded, and as a result many spores can be produced on a small region. In scattering

. Essentials of botany. Botany; Botany. THE FUNGI 267 Examine first with m.p., and then with h.p. Note: (a) The forms of the cluster-cups at various stages of growth. Compare with the cup on an anemone leaf, shown in Fig. 181. (6) The structure of the cup, surrounded by a layer of mycelium, next to which comes theperidium, or wall of the cup. The latter is filled with chains of spores (cecidiospores). Draw the cup with its contents. (c) The size and shape of the mature f spores which separate from the ends of the chains. (d) The cavities, smaller than the cluster cups and on the opposite surfa Stock Photo

RMPG41FA–. Essentials of botany. Botany; Botany. THE FUNGI 267 Examine first with m.p., and then with h.p. Note: (a) The forms of the cluster-cups at various stages of growth. Compare with the cup on an anemone leaf, shown in Fig. 181. (6) The structure of the cup, surrounded by a layer of mycelium, next to which comes theperidium, or wall of the cup. The latter is filled with chains of spores (cecidiospores). Draw the cup with its contents. (c) The size and shape of the mature f spores which separate from the ends of the chains. (d) The cavities, smaller than the cluster cups and on the opposite surfa

RMRDD7NF–. Botany for agricultural students . Botany. POTATO BLIGHT (PHYTOPHTHORA INFESTANS) 357 scattered about like spores. When the conidia germinate, instead of producing hyphae they produce zoospores, which, after swimming about for a few minutes, lose their cilia and begin to produce new hyphae. If favorably located, the new hyphae find entrance to a leaf through its stomata and start the disease anew. The oogonia and antheridia resemble those of Saprolegnia, but are produced on short hyphae within the tissues of the host. The oospore has a heavy wall and is not liberated until the tissues of the

. Diseases of plants induced by cryptogamic parasites : introduction to the study of pathogenic Fungi, slime-Fungi, bacteria, & Algae . Plant diseases; Parasitic plants; Fungi. USTILAGO. 279 Ustilago maydis (D.C.)^ (Britain and U.S. America).^ This smut of Zea Mais produces large and conspicuous deformations on leaves, leaf-sheaths, stems, roots, and all parts of the male and female flowers. These are whitish, gall-like swellings and blisters, containing a mass of gelatinous mycelium, from which spores are produced. The swellings may- attain to the size of a fist, or even larger. The spore Stock Photo

RMPG4BBD–. Diseases of plants induced by cryptogamic parasites : introduction to the study of pathogenic Fungi, slime-Fungi, bacteria, & Algae . Plant diseases; Parasitic plants; Fungi. USTILAGO. 279 Ustilago maydis (D.C.)^ (Britain and U.S. America).^ This smut of Zea Mais produces large and conspicuous deformations on leaves, leaf-sheaths, stems, roots, and all parts of the male and female flowers. These are whitish, gall-like swellings and blisters, containing a mass of gelatinous mycelium, from which spores are produced. The swellings may- attain to the size of a fist, or even larger. The spore

RMRDCGX5–. A manual of veterinary hygiene. Veterinary hygiene. 164 VETEKINAEY HYGIENE and spots. The colour is due to the spores of the fungus, which can be shaken off the leaf and are found to be of a rusty appearance. These spores, known as uredosjyores, are produced by the growth of a mycelium in the substance of the leaf, and should they get detached from the plant by air currents or otherwise, and fall on members of the grass tribe, these become infected with rust. As the summer advances, the mycelium on the leaf which has been producing the orange-red uredospores, now. Fig. 27-—Rust and Mildew (F

. Beginners' botany. Botany. Fig. 256. — Common Polypode Fern. Polypodium vulgare. Fig. 257. —Sori and Spo- rangium OF Polypode. A chain of cells lies along the top of the sporangium, which springs back elasti- cally on drying, thus dis- seminating the spores. Fig. 258. —The Brake Fruits underneath THE Revolute Edges of the Leaf. The sporangia are collected into little groups, known as sori (singular, sorus) or fruit-dots. Each sorus is covered with a thin scale or shield, known as an indusium. This indusium sepa- rates from the frond at its edges, and the sporangia are exposed. Not all ferns Stock Photo

RMPG25PM–. Beginners' botany. Botany. Fig. 256. — Common Polypode Fern. Polypodium vulgare. Fig. 257. —Sori and Spo- rangium OF Polypode. A chain of cells lies along the top of the sporangium, which springs back elasti- cally on drying, thus dis- seminating the spores. Fig. 258. —The Brake Fruits underneath THE Revolute Edges of the Leaf. The sporangia are collected into little groups, known as sori (singular, sorus) or fruit-dots. Each sorus is covered with a thin scale or shield, known as an indusium. This indusium sepa- rates from the frond at its edges, and the sporangia are exposed. Not all ferns

. Elementary botany. Botany. Fig. 337. Fig-33S. Base of leaf of isoetes, Section of plant of Isoetes engelmanii, showing cup- showing sporan,t<ium with shaped stem, and longitudinal sections of the sporan- macrospoi-cs. (Isoetes en- gia in the thickened bases of the leaves, gelmannii.) ure from the other portions of the leaf. This is a sporangium. Beside the spores on the inside of the sporangium, there are strands of sterile tissue which extend across the cavity. This is peculiar to isoetes of all the members of the class of jilants to which the ferns belong, but it will be remembered that Stock Photo

RMRE2MAW–. Elementary botany. Botany. Fig. 337. Fig-33S. Base of leaf of isoetes, Section of plant of Isoetes engelmanii, showing cup- showing sporan,t<ium with shaped stem, and longitudinal sections of the sporan- macrospoi-cs. (Isoetes en- gia in the thickened bases of the leaves, gelmannii.) ure from the other portions of the leaf. This is a sporangium. Beside the spores on the inside of the sporangium, there are strands of sterile tissue which extend across the cavity. This is peculiar to isoetes of all the members of the class of jilants to which the ferns belong, but it will be remembered that

. Minnesota plant diseases. Plant diseases. 278 Minnesota Plant Diseases. of the tree interfered with but the tree is usually stunted and may eventually die. The leaves of the diseased shoots contain less leaf-green and are paler in color than the ordi- nary leaves. The exact method of the infection by spores in this country is not yet known. A similar disease on the silver fir in Europe has recently been thoroughly investigated. It is found that the cluster-cup spores of the silver fir brooms can- not infect the silver iir leaves but can cause infection on certain plants be- longing to the pi Stock Photo

RMPG4EY2–. Minnesota plant diseases. Plant diseases. 278 Minnesota Plant Diseases. of the tree interfered with but the tree is usually stunted and may eventually die. The leaves of the diseased shoots contain less leaf-green and are paler in color than the ordi- nary leaves. The exact method of the infection by spores in this country is not yet known. A similar disease on the silver fir in Europe has recently been thoroughly investigated. It is found that the cluster-cup spores of the silver fir brooms can- not infect the silver iir leaves but can cause infection on certain plants be- longing to the pi

. Elementary botany. Botany. Kig. 249. Base of leaf of isoetes, showing sporangium with macrospores. (isoetes en- gelmannii.). Fig. 250. Section of plant of Isoetes engelmanii, showing cup- shaped stem, and longitudinal sections of the sporan- gia in the thickened bases of the leaves. ure from the other portions of the leaf. This is a sporangium. Beside the spores on the inside of the sporangium, there are strands of sterile tissue which extend across the cavity. This is peculiar to isoetes of all the members of the class of plants to which the ferns belong, but it will be remembered that ster Stock Photo

RMRDWFDG–. Elementary botany. Botany. Kig. 249. Base of leaf of isoetes, showing sporangium with macrospores. (isoetes en- gelmannii.). Fig. 250. Section of plant of Isoetes engelmanii, showing cup- shaped stem, and longitudinal sections of the sporan- gia in the thickened bases of the leaves. ure from the other portions of the leaf. This is a sporangium. Beside the spores on the inside of the sporangium, there are strands of sterile tissue which extend across the cavity. This is peculiar to isoetes of all the members of the class of plants to which the ferns belong, but it will be remembered that ster

. Minnesota plant diseases. Plant diseases. 364 Minnesota Plant Diseases.. Fic. 194.—Black rot of apple. After Clinton. fruit, when attacked, turns at first a reddish brown but later be- comes blaclf. On attacked portions of the tree the fungus pro- duces its spores. It is an "imperfect" fungus and produces spores in small capsules, which appear on the leaf, twig or fruit spots as tiny black warts. These open to the exterior by minute pores through which the spores, which are cut off of threads lin- ing the interior of the capsule, are thrown out. The treatment which is used against Stock Photo

RMPG4EK0–. Minnesota plant diseases. Plant diseases. 364 Minnesota Plant Diseases.. Fic. 194.—Black rot of apple. After Clinton. fruit, when attacked, turns at first a reddish brown but later be- comes blaclf. On attacked portions of the tree the fungus pro- duces its spores. It is an "imperfect" fungus and produces spores in small capsules, which appear on the leaf, twig or fruit spots as tiny black warts. These open to the exterior by minute pores through which the spores, which are cut off of threads lin- ing the interior of the capsule, are thrown out. The treatment which is used against

. A handbook of cryptogamic botany. Cryptogams. KiG. 27.—Section of megasporange of ^. itupquttli/olia, showing double wall of sporange, layer of tapetal cells, and mega- spores. (After Goebel, magnified.) comes to be placed in the axil or even on the base of the leaf. The ' vascular' bundle of the leaf passes beneath the sporange without sending a branch into it. As in the other heterosporous families, the two kinds of sporange present no differentiation in their early stages. The archespore is the terminal hypodermal cell of an axial row. This divides into the sporogenous tissue surrounded b Stock Photo

RMRE3N98–. A handbook of cryptogamic botany. Cryptogams. KiG. 27.—Section of megasporange of ^. itupquttli/olia, showing double wall of sporange, layer of tapetal cells, and mega- spores. (After Goebel, magnified.) comes to be placed in the axil or even on the base of the leaf. The ' vascular' bundle of the leaf passes beneath the sporange without sending a branch into it. As in the other heterosporous families, the two kinds of sporange present no differentiation in their early stages. The archespore is the terminal hypodermal cell of an axial row. This divides into the sporogenous tissue surrounded b

. A textbook of botany for colleges and universities ... Botany. Fig. 931. —A leaf of Ficus religiosa^ a tree of the tropical rain forest, showing a so- called dripping point (d). —After Stahl. Fig. 932. — A portion of a leaf of a tropical Asplenium^ illustrating reproduction by leaves; on the under sides of the ultimate leaf divisions (pinnules) are fruit dots or sori (i), in which are sporangia with their spores; on the upper sides of the pinnules are bulbils (6), which here have germi- nated while connected with the parent plant, giving rise to bulblings whose leaves (/) already are conspic Stock Photo

RMPG20WR–. A textbook of botany for colleges and universities ... Botany. Fig. 931. —A leaf of Ficus religiosa^ a tree of the tropical rain forest, showing a so- called dripping point (d). —After Stahl. Fig. 932. — A portion of a leaf of a tropical Asplenium^ illustrating reproduction by leaves; on the under sides of the ultimate leaf divisions (pinnules) are fruit dots or sori (i), in which are sporangia with their spores; on the upper sides of the pinnules are bulbils (6), which here have germi- nated while connected with the parent plant, giving rise to bulblings whose leaves (/) already are conspic

. Elementary botany. Botany. DIMORPHISM OF FERNS. 275 divisions of the pinnse, are inroUed into little spherical masses which lie close on the side of the pinna;. If we unroll one of these pinnules we find that there arc several fruit dots within protected by this roll. In fact when the spores are mature these. â V, 4 ' -^u^' Fig. 317- Sensitive fern; one fertile leaf nearly changed to vegetative leaf. pinnules open somewhat, so that the spores may be dissemi- nated. There is very little green color in these fertile leaves, and what green surface there is is very small compared ^'ith that of Stock Photo

RMRE2MCX–. Elementary botany. Botany. DIMORPHISM OF FERNS. 275 divisions of the pinnse, are inroUed into little spherical masses which lie close on the side of the pinna;. If we unroll one of these pinnules we find that there arc several fruit dots within protected by this roll. In fact when the spores are mature these. â V, 4 ' -^u^' Fig. 317- Sensitive fern; one fertile leaf nearly changed to vegetative leaf. pinnules open somewhat, so that the spores may be dissemi- nated. There is very little green color in these fertile leaves, and what green surface there is is very small compared ^'ith that of

. Botany for agricultural students . Botany. Fig. 356. — Stage of the Wheat Rust on the Barberry bush, BcrherU vulgaris. Left, leaf of Barberry, showing the affected areas which are red- dish, much thickened, and contain many cup-like depressions; right, a very much enlarged section through the affected area of the leaf, showing one of the cups (c) with chains of aecidiospores (X 200). The very small spores at (p) are the spermatia or pycniospores.. Fig. 357. — Diagram showing the life cycle of the Wheat Rust. A, wheat plants; B, barberry bush; u, uredospore; t, teleutospore; s, basidio- spore Stock Photo

RMPG4APK–. Botany for agricultural students . Botany. Fig. 356. — Stage of the Wheat Rust on the Barberry bush, BcrherU vulgaris. Left, leaf of Barberry, showing the affected areas which are red- dish, much thickened, and contain many cup-like depressions; right, a very much enlarged section through the affected area of the leaf, showing one of the cups (c) with chains of aecidiospores (X 200). The very small spores at (p) are the spermatia or pycniospores.. Fig. 357. — Diagram showing the life cycle of the Wheat Rust. A, wheat plants; B, barberry bush; u, uredospore; t, teleutospore; s, basidio- spore

RMRDWCWX–. Botany, with agricultural applications. Botany. 398 THALLOPHYTES teleospore produces a promycelium bearing the basidiospores, often called sporidia, as shown in Figure 355. Thus the teleo- spore occupies the same position in the life history of Rusts as the brand spore occupies in the life history of Smuts. The basidio- spores are scattered by the wind, and in regions where Barberry bushes grow, they come in contact with the leaves of the Barberry where they grow and produce myceha in the leaf tissues. Upon the Barberry, the mycelia produce on the under surface of the leaf small cups called

. Elements of botany. Botany; Botany. 234 ELEMENTS OF BOTANY. The mycelium of these is generally concealed in the substance of the earth, decaying wood, or other material on which the fungus grows, and the conspicuous portion of the plant is that on which the spores are borne. Lichens, familiar objects encrusting rocks or hanging in. Fig. 201. — Spore-Formation in Potato Blight {Phytophthora infestans). A, an unbranched stalk, proceeding from the mycelium m in the interior of the potato leaf, passing out of the epidermis c through the stoma sp, and bearing a single spore-case ; JB, an older gr Stock Photo

RMPG41M4–. Elements of botany. Botany; Botany. 234 ELEMENTS OF BOTANY. The mycelium of these is generally concealed in the substance of the earth, decaying wood, or other material on which the fungus grows, and the conspicuous portion of the plant is that on which the spores are borne. Lichens, familiar objects encrusting rocks or hanging in. Fig. 201. — Spore-Formation in Potato Blight {Phytophthora infestans). A, an unbranched stalk, proceeding from the mycelium m in the interior of the potato leaf, passing out of the epidermis c through the stoma sp, and bearing a single spore-case ; JB, an older gr

RMRDEABE–. Comparative morphology and biology of the fungi, mycetozoa and bacteria . Plant morphology; Fungi; Myxomycetes; Bacteriology. Fig. 130. chrysomyxa Rhododendri in a leaf of Rh. hirsutttm. Vertical section through a teleutospore-layer. e—€ epidermis of the under surface of the leaf. Adjoining the spores is the tissue of the leaf traversed and distorted by mycelial filaments m of Chrysomyxa; a a row of teleutospores which have not yet germinated; / a similar row in which the uppermost teleutospore has formed a promycelium, and on this sterigmata and sporidia are beginning to be formed in basipe

. Minnesota plant diseases. Plant diseases. Fic. 194.—Black rot of apple. After Clinton. fruit, when attacked, turns at first a reddish brown but later be- comes blaclf. On attacked portions of the tree the fungus pro- duces its spores. It is an "imperfect" fungus and produces spores in small capsules, which appear on the leaf, twig or fruit spots as tiny black warts. These open to the exterior by minute pores through which the spores, which are cut off of threads lin- ing the interior of the capsule, are thrown out. The treatment which is used against the apple scab is usually recom Stock Photo

RMPG4EJY–. Minnesota plant diseases. Plant diseases. Fic. 194.—Black rot of apple. After Clinton. fruit, when attacked, turns at first a reddish brown but later be- comes blaclf. On attacked portions of the tree the fungus pro- duces its spores. It is an "imperfect" fungus and produces spores in small capsules, which appear on the leaf, twig or fruit spots as tiny black warts. These open to the exterior by minute pores through which the spores, which are cut off of threads lin- ing the interior of the capsule, are thrown out. The treatment which is used against the apple scab is usually recom

RMRDETH0–. The fungal diseases of the common larch . Larches. 174 LEAF AND SEEDLING DISEASES to live till the spring and then to send out a small germ tube of limited growth, called the promycelium, and this bears a few, generally four, very small spores, which are known as sporidia. The sporidia are very light, and being lifted by the wind settle on the leaves of neighbouring plants. But, though they may germinate, they inevitably perish imless they happen to come in contact with a plant. Please note that these images are extracted from scanned page images that may have been digitally enhanced for rea

. Fungous diseases of plants : with chapters on physiology, culture methods and technique . Fungi in agriculture. PROTOBASIDIOMYCETES 431 produced in short chains and measure 24-28 x 18-21 fj, (Fig. 210,b). The uredesori occur on the under surface of the leaf. They are somewhat lighter colored than the casoma and are constantly inclosed by paraphyses. Individual spores are about the same in size and form, however, as the previous type (Fig. 210, c). In the same sori with the latter may be produced also the teleutospores,. Please note that these images are extracted from scanned page images tha Stock Photo

RMPG3NKB–. Fungous diseases of plants : with chapters on physiology, culture methods and technique . Fungi in agriculture. PROTOBASIDIOMYCETES 431 produced in short chains and measure 24-28 x 18-21 fj, (Fig. 210,b). The uredesori occur on the under surface of the leaf. They are somewhat lighter colored than the casoma and are constantly inclosed by paraphyses. Individual spores are about the same in size and form, however, as the previous type (Fig. 210, c). In the same sori with the latter may be produced also the teleutospores,. Please note that these images are extracted from scanned page images tha

RMRD9WNA–. A manual of weeds : with descriptions of all the most pernicious and troublesome plants in the United States and Canada, their habits of growth and distribution, with methods of control . Weeds. DESCRIPTIVE LIST AND MEANS OF CONTROL COMMON BRAKE, OR BRACKEN Ptiris aquilina, L. Other English names: Eagle Fern, Upland Fern, Turkey-foot Brake. Native. Perennial. Propagates by spores and by rootstocks. Season of leaf-production: Early spring until autumn frosts. - Fruiting fronds: Ripe in August. Range: Throughout the world. In this country most troublesome on the Pacific Coast. Habitat: Upland

. Manual of fruit diseases . Fruit. 400 MANUAL OF FRUIT DISEASES developed. In their full maturity they appear as black specks. The tissue about them is yellowish. These bodies are not found on all leaves nor on all leaflets of a given leaf. Two or three weeks after the appearance of these structures evidence of rust is seen on the lower surface of the leaves. When mature, these bodies (sori) break open and expose an orange-colored mass of spores; whence the name orange-rust. Ordi- narily these sori with their spore- masses practically cover the lower sur- face of the leaf. Affected leaves are Stock Photo

RMPG3Y6X–. Manual of fruit diseases . Fruit. 400 MANUAL OF FRUIT DISEASES developed. In their full maturity they appear as black specks. The tissue about them is yellowish. These bodies are not found on all leaves nor on all leaflets of a given leaf. Two or three weeks after the appearance of these structures evidence of rust is seen on the lower surface of the leaves. When mature, these bodies (sori) break open and expose an orange-colored mass of spores; whence the name orange-rust. Ordi- narily these sori with their spore- masses practically cover the lower sur- face of the leaf. Affected leaves are

RMRDG51N–. Essentials of botany. Botany; Botany. THE FUNGI 267 Examine first with m.p., and then with h.p. Note: (a) The forms of the cluster-cups at various stages of growth. Compare with the cup on an anemone leaf, shown in Fig. 181. (6) The structure of the cup, surrounded by a layer of mycelium, next to which comes theperidium, or wall of the cup. The latter is filled with chains of spores (cecidiospores). Draw the cup with its contents. (c) The size and shape of the mature f spores which separate from the ends of the chains. (d) The cavities, smaller than the cluster cups and on the opposite surfa

. The mushroom book. A popular guide to the identification and study of our commoner Fungi, with special emphasis on the edible varieties. Mushrooms; Cookery (Mushrooms); cbk. From Spore to Mushroom AH corn smuts, wheat smuts, leaf rusts, toadstools, puff- balls, and brackets bear their spores on club-like cells, and for this reason are put in one group, called Basidiomycetes. The fact that corn smuts and leaf rusts feed on living plants, while toad- stools, brackets, and pufifballs feed on dead plants, separates them in- to two groups ; the smuts and rustsformingthe lower group, and the other Stock Photo

RMPG44YT–. The mushroom book. A popular guide to the identification and study of our commoner Fungi, with special emphasis on the edible varieties. Mushrooms; Cookery (Mushrooms); cbk. From Spore to Mushroom AH corn smuts, wheat smuts, leaf rusts, toadstools, puff- balls, and brackets bear their spores on club-like cells, and for this reason are put in one group, called Basidiomycetes. The fact that corn smuts and leaf rusts feed on living plants, while toad- stools, brackets, and pufifballs feed on dead plants, separates them in- to two groups ; the smuts and rustsformingthe lower group, and the other

. Plant studies; an elementary botany. Botany. 272 PLANT STUDIES finally deadened spots on the leaves, where the tissues have been killed. From this internal mycelium numerous sporophores arise, coming to the surface of the host and securing the scattering of their spores, which fall upon other leaves and germinate, the new mycelia pene- trating among the tissues and begin- ning their ravages. The sporophores, af- ter rising above the surface of the leaf, branch freely; and many of them rising near together, they form little velvety patches on the surface, suggesting the name " downy mild Stock Photo

RMRE1JK2–. Plant studies; an elementary botany. Botany. 272 PLANT STUDIES finally deadened spots on the leaves, where the tissues have been killed. From this internal mycelium numerous sporophores arise, coming to the surface of the host and securing the scattering of their spores, which fall upon other leaves and germinate, the new mycelia pene- trating among the tissues and begin- ning their ravages. The sporophores, af- ter rising above the surface of the leaf, branch freely; and many of them rising near together, they form little velvety patches on the surface, suggesting the name " downy mild

RMPG25PE–. Beginners' botany. Botany. Fig. 256. — Common Polypode Fern. Polypodium vulgare. Fig. 257. —Sori and Spo- rangium OF Polypode. A chain of cells lies along the top of the sporangium, which springs back elasti- cally on drying, thus dis- seminating the spores. Fig. 258. —The Brake Fruits underneath THE Revolute Edges of the Leaf. The sporangia are collected into little groups, known as sori (singular, sorus) or fruit-dots. Each sorus is covered with a thin scale or shield, known as an indusium. This indusium sepa- rates from the frond at its edges, and the sporangia are exposed. Not all ferns

. Plants; a text-book of botany. Botany. 56 PLANT STKUCTDEES finally deadened spots on the leaves, where the tissues have been killed. From this internal mycelium numerous sjiorophores arise, coming to the surface of the host and securing the scattering of their spores, which fall upon other leaves and germinate, the new mycelia pene- trating among the tissues and begin- ning their ravages. The sporophores, af- ter rising above the surface of the leaf, branch freely ; and many of them rising near together, they form little velvety patches on the surface, suggesting the name " downy mildew Stock Photo

RMRDWB15–. Plants; a text-book of botany. Botany. 56 PLANT STKUCTDEES finally deadened spots on the leaves, where the tissues have been killed. From this internal mycelium numerous sjiorophores arise, coming to the surface of the host and securing the scattering of their spores, which fall upon other leaves and germinate, the new mycelia pene- trating among the tissues and begin- ning their ravages. The sporophores, af- ter rising above the surface of the leaf, branch freely ; and many of them rising near together, they form little velvety patches on the surface, suggesting the name " downy mildew

. Timber and some of its diseases. Timber; Trees. 156 TIMBER AND SOME OF ITS DISEASES, [chap. series of dark shining strings, looking almost like the purple-black leaf-stalks of the maidenhair fern, and. Fig. 15.—a small group of Agaricus (Arfmllarz'a) melhus. The toad-stool is taw ny-ycllow, and produces white spores; the gills are decurrent, and the stem bears a ring. The fine hair-like appendages on the pileus should be bolder, these strings branch and meander in the wood of the tree, and in the soil, and may attain even great. Please note that these images are extracted from scanned page i Stock Photo

RMPFXCWX–. Timber and some of its diseases. Timber; Trees. 156 TIMBER AND SOME OF ITS DISEASES, [chap. series of dark shining strings, looking almost like the purple-black leaf-stalks of the maidenhair fern, and. Fig. 15.—a small group of Agaricus (Arfmllarz'a) melhus. The toad-stool is taw ny-ycllow, and produces white spores; the gills are decurrent, and the stem bears a ring. The fine hair-like appendages on the pileus should be bolder, these strings branch and meander in the wood of the tree, and in the soil, and may attain even great. Please note that these images are extracted from scanned page i

. Fungi and fungicides. Fungi; Fungicides. Fig. 2. Appearance of the lungus on an apple. Fig. 3. A blotch—enlarged. apricot. It makes its appearance upon the leaves, forming reddish-brown spots, which, when mature, shrink from the surrounding tissue and are blow^n away, leaving the leaf perforated. When the fungus attacks the fruit, it first appears as minute red pimples, which are very often mistaken for scale insects. These soon develop and burst open at the top, the new spores escaping and spreading the disease. The old spot forms a scab, which spreads and joins others, and soon the surface Stock Photo

RMRE1GYT–. Fungi and fungicides. Fungi; Fungicides. Fig. 2. Appearance of the lungus on an apple. Fig. 3. A blotch—enlarged. apricot. It makes its appearance upon the leaves, forming reddish-brown spots, which, when mature, shrink from the surrounding tissue and are blow^n away, leaving the leaf perforated. When the fungus attacks the fruit, it first appears as minute red pimples, which are very often mistaken for scale insects. These soon develop and burst open at the top, the new spores escaping and spreading the disease. The old spot forms a scab, which spreads and joins others, and soon the surface

RMPG0R63–. Diseases of plants induced by cryptogamic parasites : introduction to the study of pathogenic Fungi, slime-Fungi, bacteria, & Algae . Plant diseases; Parasitic plants; Fungi. 124 PHYCOMYCETES. is very frequent on wild and cultivated Cruciferae throughout the whole world, and causes deformation of shoot, leaf, and flower.. Fig. 3i.Cj/xtopus candidta. B, Conidlophores isolated from the cushion ; the coDidia or sponuigia are united by intermediate cells. C, Sporangia breaking up CO form swarm-spores. I), Swarm-sporcs escaping. E, Swarm-spores in motile condition. F, Swarm-spores come to re

. A manual of poisonous plants, chiefly of eastern North America, with brief notes on economic and medicinal plants, and numerous illustrations. Poisonous plants. Fig. 101. Spores of Yellow Leaf Disease of Barley (Helminthosporium gramineum). a. and e. Spores germinating, d. Conidiophore. 2. Leaf browning of Corn (.Helmin- thospOTum turcicum). Spore and conidiophore to the left. To the right, conidiophore pushing through stoma. Distribution and hosts. On corn, widely distributed in North America. Poisonous properties. All of these fungi may be regarded as injurious, possibly producing stomatit Stock Photo

RMRDW23K–. A manual of poisonous plants, chiefly of eastern North America, with brief notes on economic and medicinal plants, and numerous illustrations. Poisonous plants. Fig. 101. Spores of Yellow Leaf Disease of Barley (Helminthosporium gramineum). a. and e. Spores germinating, d. Conidiophore. 2. Leaf browning of Corn (.Helmin- thospOTum turcicum). Spore and conidiophore to the left. To the right, conidiophore pushing through stoma. Distribution and hosts. On corn, widely distributed in North America. Poisonous properties. All of these fungi may be regarded as injurious, possibly producing stomatit

RMPG4AWC–. Diseases of plants induced by cryptogamic parasites : introduction to the study of pathogenic Fungi, slime-Fungi, bacteria, & Algae . Plant diseases; Parasitic plants; Fungi. GYMNOSPORANGIUM. 397 the species already described in remaining closed at the apex, the spores escaping through trellis-like slits on the lateral walls of the peridia (Fig. 234). This fungus will not germinate on apple-trees, but on pears every leaf may be thickly covered with aecidia and pycnidia, and considerable damage to the crop thereby ensue (Fig. 233)... Pig. 231.—Longitudinal section through a conical teleut

RMRDHGBJ–. Plant studies; an elementary botany. Botany. 2Y2 PLANT STUDIES fiiKilly deadened spots on the leaves, where the tissues have been killed. From this internal mycelium numerous sporojihores arise, coming to the surface of tlie host and securing the scattering of their spores, which fall u])on other leaves and germinate, the new niycelia pene- trating among the tissues and begin- ning their ravages. The sporophores, af- ter rising above the surface of the leaf, branch freely; and many of them risiiig near together, they form little velvety patches on the surface, suggesting the name " down

. Minnesota plant diseases. Plant diseases. 325 Minnesota Plant Diseases. >ft<f ife; «' The leaf blight of celery (Cercospora apii Fr.). The fungus, causing this disease is a loose spored, imperfect fungus. It causes the formation of red- dish to brownish spots on the leaves, which may spread and increase in size until the leaf is seriously injured. The fungus thrives well on plants in dry || situations and is particularly ! effective against young plants. When badly affected the leaf turns yellow and finally brown. Spots may also appear on the stem. The spores arise from upright fungus- Stock Photo

RMPG4EP7–. Minnesota plant diseases. Plant diseases. 325 Minnesota Plant Diseases. >ft<f ife; «' The leaf blight of celery (Cercospora apii Fr.). The fungus, causing this disease is a loose spored, imperfect fungus. It causes the formation of red- dish to brownish spots on the leaves, which may spread and increase in size until the leaf is seriously injured. The fungus thrives well on plants in dry || situations and is particularly ! effective against young plants. When badly affected the leaf turns yellow and finally brown. Spots may also appear on the stem. The spores arise from upright fungus-

. A text-book of elementary botany. Botany. Jlcidmm Fig. 121. of these is not known. The Escidiospores germinate, and when on the proper host-plants the germ-tube grows through the stomates. A dense mycelium is then formed in the paren- chyma of the leaf; from this mycelium grow pedicelled spores, called uredospores. They form, when they burst through the epidermis, orange-colored spots, called Red Rust. This stage was formerly designated as the genus Uredo (Fig. 122). The. Fig. 122. uredospores germinate quickly, and from their mycelium other uredospores are produced, and this process may con Stock Photo

RMRE1ND4–. A text-book of elementary botany. Botany. Jlcidmm Fig. 121. of these is not known. The Escidiospores germinate, and when on the proper host-plants the germ-tube grows through the stomates. A dense mycelium is then formed in the paren- chyma of the leaf; from this mycelium grow pedicelled spores, called uredospores. They form, when they burst through the epidermis, orange-colored spots, called Red Rust. This stage was formerly designated as the genus Uredo (Fig. 122). The. Fig. 122. uredospores germinate quickly, and from their mycelium other uredospores are produced, and this process may con

. The fungi which cause plant disease . Plant diseases; Fungi. FiQ. 159.—^A single perithecium of A. vaccinii taken from a pure culture on corn meal. After Shear. Fig. 160.—Acan- thorhynchus; a germinating as- cospore bearing the peculiar appressorium, 17, view from above. After Shear. old fallen leaves. In culture, however, it produces abundant peri- thecia. When on the leaf the perithecia are subepidermal and are sparsely scattered over the lower surface. No conidial or pycnidial form is known. Remarkable appressoria are produced by the germ tubes from the spores, Fig. 160. Sphseriacese (p. Stock Photo

RMPG4G79–. The fungi which cause plant disease . Plant diseases; Fungi. FiQ. 159.—^A single perithecium of A. vaccinii taken from a pure culture on corn meal. After Shear. Fig. 160.—Acan- thorhynchus; a germinating as- cospore bearing the peculiar appressorium, 17, view from above. After Shear. old fallen leaves. In culture, however, it produces abundant peri- thecia. When on the leaf the perithecia are subepidermal and are sparsely scattered over the lower surface. No conidial or pycnidial form is known. Remarkable appressoria are produced by the germ tubes from the spores, Fig. 160. Sphseriacese (p.

RMRDC0M3–. Manual of fruit diseases . Fruit. STRAWBERRY DISEASES 423 amass themselves beneath the cuticle of either surface of the leaf, and from these masses conidiophores bearing conidia arise. These spores develop, are scattered and produce in- fections through- out the summer; with the advent of winter conidial formation ceases, but the mycelium remains alive in the leaves until the following spring. At this time a new crop of conidia develop, which begin the cycle anew by in- fecting again the strawberry plants. Should any of these spores per- chance fall on the common cinquefoil, the disease woul

. Minnesota plant diseases. Plant diseases. 162 Minnesota Plant Diseases. the cluster-cup stage or rather just preceding it one very often finds another accessory spore-form in which small spore-cases of pear-shaped structure are produced, sunken into the oppo- site—usually upper—side of the leaf from that on which the cluster cup occurs. Inside of these pear-shaped cases the spores are produced on long threads from which they are pinched ofif just as in very similar structures found in many of the acces- sory spore-forms of the sac fungi. These spores are often ac- companied by the production Stock Photo

RMPG4FDM–. Minnesota plant diseases. Plant diseases. 162 Minnesota Plant Diseases. the cluster-cup stage or rather just preceding it one very often finds another accessory spore-form in which small spore-cases of pear-shaped structure are produced, sunken into the oppo- site—usually upper—side of the leaf from that on which the cluster cup occurs. Inside of these pear-shaped cases the spores are produced on long threads from which they are pinched ofif just as in very similar structures found in many of the acces- sory spore-forms of the sac fungi. These spores are often ac- companied by the production

. Botany, with agricultural applications. Botany. BLACK RUST OF GRAIN (PUCCINIA GRAMINIS) 399. Fig. 356. — Stage of the Wheat Rust on the Barberry bush, Berberis wlgaris. Left, leaf of Barberry, showing the affected areas which are red- dish, much thickened, and contain many cup-like depressions; right, a very much enlarged section through the affected area of the leaf, showing one of the cvips (c) with chains of aeciospores (X 200). The very small spores at (p) are the pycniospores.. Please note that these images are extracted from scanned page images that may have been digitally enhanced for Stock Photo

RMRDWCWK–. Botany, with agricultural applications. Botany. BLACK RUST OF GRAIN (PUCCINIA GRAMINIS) 399. Fig. 356. — Stage of the Wheat Rust on the Barberry bush, Berberis wlgaris. Left, leaf of Barberry, showing the affected areas which are red- dish, much thickened, and contain many cup-like depressions; right, a very much enlarged section through the affected area of the leaf, showing one of the cvips (c) with chains of aeciospores (X 200). The very small spores at (p) are the pycniospores.. Please note that these images are extracted from scanned page images that may have been digitally enhanced for

. Minnesota plant diseases. Plant diseases. Minnesota Plant Diseases. 391 posed of three cells arranged in clover-leaf fashion. The spore clusters are usually very dense and vary in size from a pin- head's width to three-quarters inch broad. The leaf under the spores colors black, so that the groups can readily be seen from the upper surface of the leaf. Cluster cups and summer spores are not known for this rust. Rust of sedges [Puccinia caricis (Sghum.) Reb.]. This is an exceedingly common rust on many Minnesota sedges. The summer and winter spores are produced on the sedge plant and the clus Stock Photo

RMPG4EH2–. Minnesota plant diseases. Plant diseases. Minnesota Plant Diseases. 391 posed of three cells arranged in clover-leaf fashion. The spore clusters are usually very dense and vary in size from a pin- head's width to three-quarters inch broad. The leaf under the spores colors black, so that the groups can readily be seen from the upper surface of the leaf. Cluster cups and summer spores are not known for this rust. Rust of sedges [Puccinia caricis (Sghum.) Reb.]. This is an exceedingly common rust on many Minnesota sedges. The summer and winter spores are produced on the sedge plant and the clus

. Microbes, ferments and moulds . Bacteria; Fungi; Fermentation. 36 MICROBES, FERMENTS, AND MOULDS. oidium. Brown patches appear on the upper surface of the leaf, as if it had been scorched; and in corre- spondence with these there is a delicate down " like the whiteness of a slight hoar-frost" (Vaissier) on its lower surface. The hyphse issuing from the mycelium ramify at right angles, and these branches bear the spores, as in the potato-fungus, Peronospora infestans (Figs. 17,18). These numerous spores, diffused through the air, are powerful sources of contagion.. Fig. 17.—Mildew • Stock Photo

RMRDJ5C8–. Microbes, ferments and moulds . Bacteria; Fungi; Fermentation. 36 MICROBES, FERMENTS, AND MOULDS. oidium. Brown patches appear on the upper surface of the leaf, as if it had been scorched; and in corre- spondence with these there is a delicate down " like the whiteness of a slight hoar-frost" (Vaissier) on its lower surface. The hyphse issuing from the mycelium ramify at right angles, and these branches bear the spores, as in the potato-fungus, Peronospora infestans (Figs. 17,18). These numerous spores, diffused through the air, are powerful sources of contagion.. Fig. 17.—Mildew •

. Manual of tree diseases . Trees. 342 MANUAL OF TREE DISEASES common and is found generally distributed throughout the northern states. The other two are apparently rare and are kliown only in Colorado and Utah. The leaf- rusts are impor- tant on yoimg trees because defoliation often results. Symptoms, The three rust- diseases are very similar in appear- ance. In early simi- mer the affected leaves show yellow- ish areas on which are borne small orange-yellow pus- tules. These pus- tules appear pow- dery, due to the mass of spores they contain. Later in the season on the The. Fig. 70. —Powder Stock Photo

RMPG0D3T–. Manual of tree diseases . Trees. 342 MANUAL OF TREE DISEASES common and is found generally distributed throughout the northern states. The other two are apparently rare and are kliown only in Colorado and Utah. The leaf- rusts are impor- tant on yoimg trees because defoliation often results. Symptoms, The three rust- diseases are very similar in appear- ance. In early simi- mer the affected leaves show yellow- ish areas on which are borne small orange-yellow pus- tules. These pus- tules appear pow- dery, due to the mass of spores they contain. Later in the season on the The. Fig. 70. —Powder

RMRDE323–. Minnesota plant diseases. Plant diseases. Minnesota Plant Diseases. 389 The fungus threads, which are found in the swollen parts of the host plant and which cause the stimulation, whereby the increase of growth or swelling of the stem takes place, form their winter rust-spores inside of the cells of the epidermis of. Fig. 206.—Sunflower rust. Winter and summer spore clusters on the leaf of <l sunflower. Original. the host. This epidermis is much altered on account of the action of the fungus. Its cells have thin, instead of thick, outer walls, and are much increased in size. These spores

. Manual of tree diseases . Trees. 198 MANUAL OP TREE DISEASES produced on the small twigs of the red juniper. When very young, the galls can be seen to start as outgrowths of the juniper leaves (Fig. 31). The tissues of the leaf are stimulated to ovei^ growth and finally form, in a single season, the large cedar- apples, which are often an inch in diameter (Fig. 32). In this. Fig. 33. — Cedar-apple in spring of second year, showing expanded spore-horns. condition they pass the winter, and the following spring brown horns of spores are pushed out from the surface of the cedar- apples (Fig. 33) Stock Photo

RMPG14KM–. Manual of tree diseases . Trees. 198 MANUAL OP TREE DISEASES produced on the small twigs of the red juniper. When very young, the galls can be seen to start as outgrowths of the juniper leaves (Fig. 31). The tissues of the leaf are stimulated to ovei^ growth and finally form, in a single season, the large cedar- apples, which are often an inch in diameter (Fig. 32). In this. Fig. 33. — Cedar-apple in spring of second year, showing expanded spore-horns. condition they pass the winter, and the following spring brown horns of spores are pushed out from the surface of the cedar- apples (Fig. 33)

. The British rust fungi (Uredinales) their biology and classification. Rust fungi. 204 PUCCINIA On Viola palustris. Rare; Wales, Scotland, and near Birmingham. The beginnings of the sori may be seen by the middle of May. (Fig. 151.) This species is easily recognised by its large and pulvinate groups of sori. The mycelium spreads considerably beyond the part occupied by the spores, and consequently causes large yellow patches, usually only one or at most two on each leaf, each the result of a separate infection by the basidiospores. P. asarina Cooke, Handbook, p. 504, Plowright, Uredinese, p. Stock Photo

RMRE37DN–. The British rust fungi (Uredinales) their biology and classification. Rust fungi. 204 PUCCINIA On Viola palustris. Rare; Wales, Scotland, and near Birmingham. The beginnings of the sori may be seen by the middle of May. (Fig. 151.) This species is easily recognised by its large and pulvinate groups of sori. The mycelium spreads considerably beyond the part occupied by the spores, and consequently causes large yellow patches, usually only one or at most two on each leaf, each the result of a separate infection by the basidiospores. P. asarina Cooke, Handbook, p. 504, Plowright, Uredinese, p.

. Beginners' botany. Botany. STUDIES IN CRYPTOGAMS 193 each producing a short branch with a httle spo- ridium, s. A most remarkable circumstance in the life history of the wheat rust is the fact that the my- celium produced by the sporidium can live only in barberry leaves, and it follows that if no-bar- berry bushes are in the neighborhood the sporidia finally perish. Those which happen to lodge on a barberry bush germinate immediately, produc- ing a mycelium that enters the barberry leaf and grows within its tissues. Very soon the fungus produces a new kind of spores on the barberry leaves. Stock Photo

RMPG0NGX–. Beginners' botany. Botany. STUDIES IN CRYPTOGAMS 193 each producing a short branch with a httle spo- ridium, s. A most remarkable circumstance in the life history of the wheat rust is the fact that the my- celium produced by the sporidium can live only in barberry leaves, and it follows that if no-bar- berry bushes are in the neighborhood the sporidia finally perish. Those which happen to lodge on a barberry bush germinate immediately, produc- ing a mycelium that enters the barberry leaf and grows within its tissues. Very soon the fungus produces a new kind of spores on the barberry leaves.

. Experimental morphology. Protoplasm; Growth. §2] UPON THE DIRECTION OF GROWTH 341 by a fine needle point. The solutions were injected into the leaf of Tradescantia, spores were sown upon its stoma-bearing surface, and the whole was kept in a moist chamber. If the solution was attractive, the growing hyphse penetrated into the stomata, whereas in the absence of the solution they showed no tendency to do so. Similarly, spores sown on the perforated plate sent hyphse downwards through the holes when the plate was floating on attractive solutions, but not otherwise. Mole-. FiG. 94. — Upper figur Stock Photo

RMRE0GA1–. Experimental morphology. Protoplasm; Growth. §2] UPON THE DIRECTION OF GROWTH 341 by a fine needle point. The solutions were injected into the leaf of Tradescantia, spores were sown upon its stoma-bearing surface, and the whole was kept in a moist chamber. If the solution was attractive, the growing hyphse penetrated into the stomata, whereas in the absence of the solution they showed no tendency to do so. Similarly, spores sown on the perforated plate sent hyphse downwards through the holes when the plate was floating on attractive solutions, but not otherwise. Mole-. FiG. 94. — Upper figur

$. Mosses with a hand-lens; a non-technical handbook of the more common and more easily recognized mosses of the north-eastern United States. Mosses. Figure 87. Pnllavicinia Lyellii (After Sullivant.) Plant; part of thallus with involucre, perianth and ca- lyptra; part of perianth cut away to show young calyp- tra; capsule closed and open; antheridium enclosed in a leaf; elater and spores. in swampy places and on PALLAVICINIA. p. Lyellii S. F. Gray {Steetsia of authors) has a flat creeping thallus, J4 to nearly ^ inch wide, sometimes reaching four inches in length, with margin somewhat sinuate, Stock Photo$

RMPG3J2H–. Mosses with a hand-lens; a non-technical handbook of the more common and more easily recognized mosses of the north-eastern United States. Mosses. Figure 87. Pnllavicinia Lyellii (After Sullivant.) Plant; part of thallus with involucre, perianth and ca- lyptra; part of perianth cut away to show young calyp- tra; capsule closed and open; antheridium enclosed in a leaf; elater and spores. in swampy places and on PALLAVICINIA. p. Lyellii S. F. Gray {Steetsia of authors) has a flat creeping thallus, J4 to nearly ^ inch wide, sometimes reaching four inches in length, with margin somewhat sinuate,

RMRDC165–. Botany for agricultural students . Botany. 398 THALLOPHYTES teleutospore produces a promycelium bearing the basidiospores, often called sporidia, as shown in Figure 355. Thus the teleuto- spore occupies the same position in the life history of Rusts as the brand spore occupies in the life history of Smuts. The basidio spores are scattered by the wind, and in regions where Barberry bushes grow, they come in contact with the leaves of the Barberry where they grow and produce mycelia in the leaf tissues. Upon the Barberry, the mycelia produce on the under surface of the leaf small cups called a

. The fungi which cause plant disease . Plant diseases; Fungi. THE FUNGI WHICH CAUSE PLANT DISEASE 623 tapering, obtuse, basally dark-brown, slightly constricted at the septa, 5 to 9 times cross-septate and 0-5 times longitudinally septate. It causes injury on carnation leaves and stems. A. solani (E. & M.) Jones & Grout. '"• ^''''"'-'" Spots brown, circular to elliptic, concentrically zonate, amphige- nous, irregularly scattered over the leaf surface; mycelium. Fio. 422.—A. solani, 2, spores germinating and penetrating the living potato leaf; 5, showing cateuulatiou of Stock Photo

RMPG45GC–. The fungi which cause plant disease . Plant diseases; Fungi. THE FUNGI WHICH CAUSE PLANT DISEASE 623 tapering, obtuse, basally dark-brown, slightly constricted at the septa, 5 to 9 times cross-septate and 0-5 times longitudinally septate. It causes injury on carnation leaves and stems. A. solani (E. & M.) Jones & Grout. '"• ^''''"'-'" Spots brown, circular to elliptic, concentrically zonate, amphige- nous, irregularly scattered over the leaf surface; mycelium. Fio. 422.—A. solani, 2, spores germinating and penetrating the living potato leaf; 5, showing cateuulatiou of

. Introduction to botany. Botany. /'-* Fig. 209. The rootstock of a fern The outer part of the stem is made up of hard tissue, aud in the interior are also bundles of hard tissue (s) known as sclerenchyma; numerous woody bundles (f.b) are also surrounded by the large amount of pith. Fig. 210. Diagram of cross section of a fern leaf On the underside of the leaf are the indusium (i) and the sporangia (s); within the sporangia are the spores. After Engler and Prantl. Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - colora Stock Photo

RMRE2JN1–. Introduction to botany. Botany. /'-* Fig. 209. The rootstock of a fern The outer part of the stem is made up of hard tissue, aud in the interior are also bundles of hard tissue (s) known as sclerenchyma; numerous woody bundles (f.b) are also surrounded by the large amount of pith. Fig. 210. Diagram of cross section of a fern leaf On the underside of the leaf are the indusium (i) and the sporangia (s); within the sporangia are the spores. After Engler and Prantl. Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - colora

. Minnesota plant diseases. Plant diseases. Minnesota Plant Diseases. 569 celium is at work witliin the leaf. On the under surface these patches show at first a faint light grey shimmer, which later de- velops into the grey mold-like growth of the fully developed patches of the summer spores. These patches spread rapidly and the whole leaf, in the course of a few weeks, dies, becomes brittle and useless as a starch-making organ and dangerous as a pro-. FlG. 197.—Downy mildew of grape. On the right is a healthy bunch of grapes; on the left a bunch badly diseased. Original. ducer of the fungus s Stock Photo

RMPG4EJH–. Minnesota plant diseases. Plant diseases. Minnesota Plant Diseases. 569 celium is at work witliin the leaf. On the under surface these patches show at first a faint light grey shimmer, which later de- velops into the grey mold-like growth of the fully developed patches of the summer spores. These patches spread rapidly and the whole leaf, in the course of a few weeks, dies, becomes brittle and useless as a starch-making organ and dangerous as a pro-. FlG. 197.—Downy mildew of grape. On the right is a healthy bunch of grapes; on the left a bunch badly diseased. Original. ducer of the fungus s

RMRDW23G–. A manual of poisonous plants, chiefly of eastern North America, with brief notes on economic and medicinal plants, and numerous illustrations. Poisonous plants. FUNGI IMPERFECTI—SCOLECOTRICHUM 283. Fig. 101a. Spot Disease of Orchard Grass {Scolectotrichum graminis). Cross- section of leaf, general fruiting layer of fungus with conidiophores and conidia. A, spores germinating. After Trelease.. Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and appearance of these illustrations may not perfectly resemble t

. The fungi which cause plant disease . Plant diseases; Fungi. THE FUNGI WHICH CAUSE PLANT DISEASE 561 spots but since diseased tissue soon drops out they are often diffi- cult to find. Bark spots are often sterile. Late in the season spores abound scattered on the surfaces of twigs, especially at rough places, as near leaf scars. Spores near bud scales penetrate them with a mycelium and kill the buds or if on bark they enter the twig and produce dead spots. C. foliicolum Fuckel.^o^ Spots epiphyllous, ochraceous, indefinite; acervuli punctiform, erumpent; conidia ellipsoid-oblong, 17 x 6-7 /i, Stock Photo

RMPG45MH–. The fungi which cause plant disease . Plant diseases; Fungi. THE FUNGI WHICH CAUSE PLANT DISEASE 561 spots but since diseased tissue soon drops out they are often diffi- cult to find. Bark spots are often sterile. Late in the season spores abound scattered on the surfaces of twigs, especially at rough places, as near leaf scars. Spores near bud scales penetrate them with a mycelium and kill the buds or if on bark they enter the twig and produce dead spots. C. foliicolum Fuckel.^o^ Spots epiphyllous, ochraceous, indefinite; acervuli punctiform, erumpent; conidia ellipsoid-oblong, 17 x 6-7 /i,

. Essentials of botany. Botany; Botany. THE FUNGI 257 Examine first with m.p., and then with h.p. Note : (a) The forms of the cluster-cups at various stages of growth. Compare with the cup on an anemone leaf, shown in Fig. 181. (b) The structure of the cup, surrounded by a layer of mycelium, next to which comes theperidium, or wall of the cup. The latter is filled with chains of spores (cecidiospores). Draw the cup with its contents. (c) The size and shape of the mature ^ spores which separate from the ends of the chains. (rf) The cavities, smaller than the cluster cups and on the opposite sur Stock Photo

RMRDWFGW–. Essentials of botany. Botany; Botany. THE FUNGI 257 Examine first with m.p., and then with h.p. Note : (a) The forms of the cluster-cups at various stages of growth. Compare with the cup on an anemone leaf, shown in Fig. 181. (b) The structure of the cup, surrounded by a layer of mycelium, next to which comes theperidium, or wall of the cup. The latter is filled with chains of spores (cecidiospores). Draw the cup with its contents. (c) The size and shape of the mature ^ spores which separate from the ends of the chains. (rf) The cavities, smaller than the cluster cups and on the opposite sur

. Lessons in botany. Botany. FUNGI: WHEAT RUST. 133 For a fuller study of the wheat rust and of other fungi see the author's larger " Elementary Botany," Chapters XX, XXI.. Wheat rust. Fig. 113- Section through leaf of barberry at point affected with the cluster-cup stage of the wheat rust; spermagonia above, aecidia below. (After Marshall-Ward.) Synopsis. A parasite on grains, grasses, and on the barberry. Vegetative part of plant; mycelium growing within the tissues of the host. Fruiting part of the plant. 1st. Red rust (one-celled spores in pustules on blades and stems of the whea Stock Photo

RMPG00XN–. Lessons in botany. Botany. FUNGI: WHEAT RUST. 133 For a fuller study of the wheat rust and of other fungi see the author's larger " Elementary Botany," Chapters XX, XXI.. Wheat rust. Fig. 113- Section through leaf of barberry at point affected with the cluster-cup stage of the wheat rust; spermagonia above, aecidia below. (After Marshall-Ward.) Synopsis. A parasite on grains, grasses, and on the barberry. Vegetative part of plant; mycelium growing within the tissues of the host. Fruiting part of the plant. 1st. Red rust (one-celled spores in pustules on blades and stems of the whea

RMRDC15Y–. Botany for agricultural students . Botany. BLACK RUST OF GRAIN (PUCCINIA GRAMINIS) 399. Fig. 356. — Stage of the Wheat Rust on the Barberry bush, BcrherU vulgaris. Left, leaf of Barberry, showing the affected areas which are red- dish, much thickened, and contain many cup-like depressions; right, a very much enlarged section through the affected area of the leaf, showing one of the cups (c) with chains of aecidiospores (X 200). The very small spores at (p) are the spermatia or pycniospores.. Please note that these images are extracted from scanned page images that may have been digitally enh

. Fungous diseases of plants : with chapters on physiology, culture methods and technique . Fungi in agriculture. FUNGI IMPERFECTI 311 as in a moist" chamber, the length mentioned may be considerably exceeded. After the death of a leaf, spores may be produced over the entire surface. Spores found upon old leaves in the field five months after the beets were harvested were able to germinate. The fresh spores germinate readily in ordinary nutrient media, and pure cultures may be obtained by the poured plate method. After a growth of a few days the colonies show up well. The sub- merged myce Stock Photo

RMPG3YDB–. Fungous diseases of plants : with chapters on physiology, culture methods and technique . Fungi in agriculture. FUNGI IMPERFECTI 311 as in a moist" chamber, the length mentioned may be considerably exceeded. After the death of a leaf, spores may be produced over the entire surface. Spores found upon old leaves in the field five months after the beets were harvested were able to germinate. The fresh spores germinate readily in ordinary nutrient media, and pure cultures may be obtained by the poured plate method. After a growth of a few days the colonies show up well. The sub- merged myce

RMRDE33G–. Minnesota plant diseases. Plant diseases. Fic. 194.—Black rot of apple. After Clinton. fruit, when attacked, turns at first a reddish brown but later be- comes blaclf. On attacked portions of the tree the fungus pro- duces its spores. It is an "imperfect" fungus and produces spores in small capsules, which appear on the leaf, twig or fruit spots as tiny black warts. These open to the exterior by minute pores through which the spores, which are cut off of threads lin- ing the interior of the capsule, are thrown out. The treatment which is used against the apple scab is usually recom

. Mosses with a hand-lens; a non-technical handbook of the more common and more easily recognized mosses of the north-eastern United States. Mosses. MOSSES WITH A HAND-LENS 173. Figure 100. Scapania nemorosa. Branch X 2. Leaf X 10. tinctly longer than broad and are strongly ciliate-dentate. The leaves are stiff and only a little larger above. The perianth mouth is ciliate-dentate. The spores mature in spring. S. UNDULATA (L.) Dum., the Aquatic Scapania, is less common than the pre- ceding and grows on stones in streams or in very wet places. It is green, or frequently red or dark brownish-red. Stock Photo

RMPG3J02–. Mosses with a hand-lens; a non-technical handbook of the more common and more easily recognized mosses of the north-eastern United States. Mosses. MOSSES WITH A HAND-LENS 173. Figure 100. Scapania nemorosa. Branch X 2. Leaf X 10. tinctly longer than broad and are strongly ciliate-dentate. The leaves are stiff and only a little larger above. The perianth mouth is ciliate-dentate. The spores mature in spring. S. UNDULATA (L.) Dum., the Aquatic Scapania, is less common than the pre- ceding and grows on stones in streams or in very wet places. It is green, or frequently red or dark brownish-red.

RMRE0REB–. The mushroom book : a popular guide to the identification and study of our commoner Fungi, with special emphasis on the edible varieties . Mushrooms; Mushrooms, Edible; Cookery (Mushrooms); cbk. Section to show gills All corn smuts, wheat smuts, leaf rusts, toadstools, puff- balls, and brackets bear their spores on club-like cells, and for this reason are put in one group, called Basidiomycetes. The fact that corn smuts and leaf rusts feed on living plants, while toad- stools, brackets, and puffballs feed on dead plants, separates them in- to two groups ; the smuts and rustsforming the lower

. The fungi which cause plant disease . Plant diseases; Fungi. THE FUNGI WHICH CAUSE PLANT DISEASE 397 EricacejE. Cultural work and studies in infection are needed be- fore species can be properly delimited.'' E. vaccinii (Fcl.) Wor. occurs on Vaccinium vitis idaea, forming large blisters on the leaves, rarely on petioles and stems, discoloration red or purple. The fungus appears as a white bloom on the under surface of the leaf; spores narrowly fusiform, 5-8 x 1-2 n. Richards ^ who studied E. vaccinii and E. an- dromedse from inoculations concludes: "Aside from the form of the distortion Stock Photo

RMPG45XX–. The fungi which cause plant disease . Plant diseases; Fungi. THE FUNGI WHICH CAUSE PLANT DISEASE 397 EricacejE. Cultural work and studies in infection are needed be- fore species can be properly delimited.'' E. vaccinii (Fcl.) Wor. occurs on Vaccinium vitis idaea, forming large blisters on the leaves, rarely on petioles and stems, discoloration red or purple. The fungus appears as a white bloom on the under surface of the leaf; spores narrowly fusiform, 5-8 x 1-2 n. Richards ^ who studied E. vaccinii and E. an- dromedse from inoculations concludes: "Aside from the form of the distortion

. Outlines of plant life : with special reference to form and function . Botany. 38 OUTLINES OF PLANT LIFE. mount and show the mycelium of the fungus consisting of tangled hyphse ramifying among the cells of leaf. (TJT[ 44, 45.) Examine a dried leaf. Observe 2. The white blisters (sfore beds) here and there on the surface ; the thin membrane (the epidermis of the leaf) by which they are covered ; in older blisters the cracking and final disappearance of this skin. (1 269, fig. 141.) 3. The white powdery spores which jar out or can be dislodged vifith needle. 47. Fusion.—When the hyphae of a fu Stock Photo

RMRDHBR5–. Outlines of plant life : with special reference to form and function . Botany. 38 OUTLINES OF PLANT LIFE. mount and show the mycelium of the fungus consisting of tangled hyphse ramifying among the cells of leaf. (TJT[ 44, 45.) Examine a dried leaf. Observe 2. The white blisters (sfore beds) here and there on the surface ; the thin membrane (the epidermis of the leaf) by which they are covered ; in older blisters the cracking and final disappearance of this skin. (1 269, fig. 141.) 3. The white powdery spores which jar out or can be dislodged vifith needle. 47. Fusion.—When the hyphae of a fu

. Lessons in botany. Botany. 204. BOTANY. organs. Now the fern leaf bears the spores and the spore forms the prothallium. So it is in the flowering plants. The stairen bears the small spores—pollen grains—and the pollen grain. Fig- 182. Diagrammatic section of a flower. Ke, calyx; K, corolla ; A the filament, and <z, the anther, of the stamen ; p, pollen-cells, some in the anther, others on the stigma ; F, the ovary, surmounted by the style, g, and the stigma, n (this ovary contains one ovule, which has a single coat, i, enclosing the ovule-body, S) ; em, the embryo-sac; E, germ-cell; /j, a Stock Photo

RMPG00J4–. Lessons in botany. Botany. 204. BOTANY. organs. Now the fern leaf bears the spores and the spore forms the prothallium. So it is in the flowering plants. The stairen bears the small spores—pollen grains—and the pollen grain. Fig- 182. Diagrammatic section of a flower. Ke, calyx; K, corolla ; A the filament, and <z, the anther, of the stamen ; p, pollen-cells, some in the anther, others on the stigma ; F, the ovary, surmounted by the style, g, and the stigma, n (this ovary contains one ovule, which has a single coat, i, enclosing the ovule-body, S) ; em, the embryo-sac; E, germ-cell; /j, a

. The British rust fungi (Uredinales) their biology and classification. Rust fungi. COLEOSPORIUM 323. Teleutospores. Sori filling large intercellular spaces of the mesophyll towards the lower sur- face of the leaf; spores prismatic, length up to 140/x, breadth 18— 28 fj,; epispore 18—21 fj, thick, or more, at the summit. ^cidia on (?both) leaves of Pinus silvestris; uredo- and teleu- tospores on Tussilago Farfara, May—November, very common. (Fig. 243.) The connection of the spore-forms on the alternate hosts has been demon- strated by Plowright, Klebahn, Fischer and Wagner. Klebahn and Fischer Stock Photo

RMRE2G9C–. The British rust fungi (Uredinales) their biology and classification. Rust fungi. COLEOSPORIUM 323. Teleutospores. Sori filling large intercellular spaces of the mesophyll towards the lower sur- face of the leaf; spores prismatic, length up to 140/x, breadth 18— 28 fj,; epispore 18—21 fj, thick, or more, at the summit. ^cidia on (?both) leaves of Pinus silvestris; uredo- and teleu- tospores on Tussilago Farfara, May—November, very common. (Fig. 243.) The connection of the spore-forms on the alternate hosts has been demon- strated by Plowright, Klebahn, Fischer and Wagner. Klebahn and Fischer

. Botany for agricultural students . Botany. Fig. 322. —Pus- tules on the bark of n Chestnut caused by the Chestnut Blight Fungus. From Bulletin 380, U. S. Dept. Agri- culture, 1917. Fig. 323. — Powdery Mildew on an Apple leaf. The light areas arc due to the presence of many superficial hyphae. From BuUelin ISO, Maine Agr. Exp. Sta. produced {Fig. 322). The summer spores are extruded in threads and spread the disease to other trees. In autumn these same pustules develop deeply buried perithecia in which the ascospores (winter spores) develop. The ascospores germinate the next spring and when c Stock Photo

RMPG4B1B–. Botany for agricultural students . Botany. Fig. 322. —Pus- tules on the bark of n Chestnut caused by the Chestnut Blight Fungus. From Bulletin 380, U. S. Dept. Agri- culture, 1917. Fig. 323. — Powdery Mildew on an Apple leaf. The light areas arc due to the presence of many superficial hyphae. From BuUelin ISO, Maine Agr. Exp. Sta. produced {Fig. 322). The summer spores are extruded in threads and spread the disease to other trees. In autumn these same pustules develop deeply buried perithecia in which the ascospores (winter spores) develop. The ascospores germinate the next spring and when c

RMRDA879–. Beginners' botany. Botany. Fig. 256. — Common Polypode Fern. Polypodium vulgare. Fig. 257. —Sori and Spo- rangium OF Polypode. A chain of cells lies along the top of the sporangium, which springs back elasti- cally on drying, thus dis- seminating the spores. Fig. 258. —The Brake Fruits underneath THE Revolute Edges of the Leaf. The sporangia are collected into little groups, known as sori (singular, sorus) or fruit-dots. Each sorus is covered with a thin scale or shield, known as an indusium. This indusium sepa- rates from the frond at its edges, and the sporangia are exposed. Not all ferns

. Lessons in botany. Botany. Fig Under side dium spinulosum showing dots (sori). of pinna of Aspi- fruit. Fig- '35- Four pinnjE of adiantum, showing recurved margins which cover the sporangia. fern, or of any one of many of the species of the true ferns just at the ripening of the spores, and place a portion of a leaf on a piece of white paper in a dry room, in a very short time we shall see that the paper is being dusted with minute brown objects which fly out from the leaf. Now if we take a portion of the same. Please note that these images are extracted from scanned page images that may hav Stock Photo

RMPG00T2–. Lessons in botany. Botany. Fig Under side dium spinulosum showing dots (sori). of pinna of Aspi- fruit. Fig- '35- Four pinnjE of adiantum, showing recurved margins which cover the sporangia. fern, or of any one of many of the species of the true ferns just at the ripening of the spores, and place a portion of a leaf on a piece of white paper in a dry room, in a very short time we shall see that the paper is being dusted with minute brown objects which fly out from the leaf. Now if we take a portion of the same. Please note that these images are extracted from scanned page images that may hav

. The British rust fungi (Uredinales) their biology and classification. Rust fungi. 382 HEMILEIA On leaves of Gattleya Dowiana Batem., imported from Costa Rica, 1899. (Fig. 285.) Only a small patch of Rust was present on the leaf when the plant was received from Costa Rica, but this continued to increase in size and the falling spores infected other leaves. The uredospores germinated readily, and young Gattleya leaves, inoculated on the under surface, produced mature uredospores in thirteen days. No success attended the efforts to infect other orchids, not belonging to the genus Gattleya. This Stock Photo

RMRE2FXB–. The British rust fungi (Uredinales) their biology and classification. Rust fungi. 382 HEMILEIA On leaves of Gattleya Dowiana Batem., imported from Costa Rica, 1899. (Fig. 285.) Only a small patch of Rust was present on the leaf when the plant was received from Costa Rica, but this continued to increase in size and the falling spores infected other leaves. The uredospores germinated readily, and young Gattleya leaves, inoculated on the under surface, produced mature uredospores in thirteen days. No success attended the efforts to infect other orchids, not belonging to the genus Gattleya. This

. Mosses with a hand-lens; a non-technical handbook of the more common and more easily recognized mosses of the north-eastern United States. Mosses. Figure 100. Scapania nemorosa. Branch X 2. Leaf X 10. tinctly longer than broad and are strongly ciliate-dentate. The leaves are stiff and only a little larger above. The perianth mouth is ciliate-dentate. The spores mature in spring. S. UNDULATA (L.) Dum., the Aquatic Scapania, is less common than the pre- ceding and grows on stones in streams or in very wet places. It is green, or frequently red or dark brownish-red. The leaves are flaccid and d Stock Photo

RMPG3HYN–. Mosses with a hand-lens; a non-technical handbook of the more common and more easily recognized mosses of the north-eastern United States. Mosses. Figure 100. Scapania nemorosa. Branch X 2. Leaf X 10. tinctly longer than broad and are strongly ciliate-dentate. The leaves are stiff and only a little larger above. The perianth mouth is ciliate-dentate. The spores mature in spring. S. UNDULATA (L.) Dum., the Aquatic Scapania, is less common than the pre- ceding and grows on stones in streams or in very wet places. It is green, or frequently red or dark brownish-red. The leaves are flaccid and d

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