Search results
Results from the WOW.Com Content Network
Pyrenophora tritici-repentis and Drechslera tritici-repentis is a necrotrophic plant pathogen of fungal origin, phylum Ascomycota. [1] The pathogen causes a disease originally named yellow spot but now commonly called tan spot, yellow leaf spot, yellow leaf blotch or helminthosporiosis.
Symptoms can overlap across causal agents, however differing signs and symptoms of certain pathogens can lead to the diagnosis of the type of leaf spot disease. Prolonged wet and humid conditions promote leaf spot disease and most pathogens are spread by wind, splashing rain or irrigation that carry the disease to other leaves. [2]
The lesions found in Northern corn leaf blight are more acute if the leaves above the ear are infected during or soon after flowering of the plant. [4] In susceptible corn hybrids, lesions are also found on the husk of ears or leaf sheaths. In partially resistant hybrids, these lesions tend to be smaller due to reduced spore formation.
A raspberry leaf spot infection initially causes dark green circular spots on the upper side of young leaves, which will eventually turn tan or gray. [3] These spots are typically 1–2 millimetres (0.039–0.079 in) in diameter, but can get as big as 4–6 millimetres (0.16–0.24 in). [4]
The spots merge, eventually forming irregular necrotic patches on the leaves. Leaf spots may be surrounded by a zone of yellow leaf tissue of varying width. Spot may also appear on the leaf sheaths, necks and heads of the plant. Heavily infected leaves dry up completely, and infections on the flag leaf during kernel filling are the most serious.
Significant variation in symptoms is seen between diseases, though some symptoms are expressed across species. On a macroscopic scale, plants infected with a X. fastidiosa-related disease exhibit symptoms of water, zinc, and iron deficiencies, [27] manifesting as leaf scorching and stunting in leaves turning them yellowish-brown, gummy substance around leaves, [27] fruit reduction in size and ...
Alternaria leaf spot or Alternaria leaf blight are a group of fungal diseases in plants, that have a variety of hosts. [ 1 ] [ 2 ] [ 3 ] The diseases infects common garden plants, such as cabbage, and are caused by several closely related species of fungi. [ 4 ]
Lupinus polyphyllus, the large-leaved lupine, big-leaved lupine, many-leaved lupine, [2] blue-pod lupine, [3] or, primarily in cultivation, garden lupin, is a species of lupine (lupin) native to western North America from southern Alaska and British Columbia [4] and western Wyoming, and south to Utah and California.