Search results
Results from the WOW.Com Content Network
The most common cause of bacterial leaf spots are by bacteria in the genera Pseudomonas and Xanthomonas. For example, Pseudomonas syringae pv. tabaci is known to cause angular leaf spots of cucumber, Pseudomonas syringae pv. phaseolicola to cause bean leaf spot and Xanthomonas campestris pv. phaseoli, angular leaf spot of cotton. [7]
Fungal diseases; Common name: Scientific name: Plants affected: Alternaria leaf spot Alternaria panax: B, D, Fl, P,S Anthracnose Colletotrichum trichellum: H Cercospora leaf spot Cercospora spp. B, S Damping-off Pythium spp. B,Fj,S Gray mold Botrytis cinerea: H Phyllosticta leaf spot Phyllosticta concentrica. Discochora philoprina [teleomorph] H
This disease affects strawberry plant foliage causing purple spots 1 ⁄ 8 to 1 ⁄ 4 in (3.2 to 6.4 mm) in diameter across on the upper side of the leaves. [3] At first, the whole spot is purple but as the disease matures the center of the leaf spots on older leaves become tan or gray, then almost white. Lesions on younger leaves remain light ...
The fungus is spread by wind. Affected leaves fall prior to healthy ones and plants may be defoliated in serious infections. Anthracnose Sphaceloma rosarum on Rosa rugosa. Anthracnose Sphaceloma rosarum – Spots caused by this fungus originate from a point where leaves are water soaked, usually unnoticeable at first, until they turn black with ...
Most commonly Cephaleuros virescens is identified by the leaf spots it causes. Theses leaf spots are an orange-brown rust in color and usually occur entirely on the upper leaf surface, although leaf spots on the undersides of infected leaves have been reported. The spots are fuzzy in texture and approximately 2 cm (0.8 in) in diameter. [2]
However, leaf spots may, in advanced stages, expand to kill entire areas of leaf tissue and thus exhibit blight symptoms. Blights are often named after their causative agent. For example, Colletotrichum blight is named after the fungus Colletotrichum capsici, and Phytophthora blight is named after the water mold Phytophthora parasitica. [11]
Phyllosticta leaf spot Phyllosticta erratica Phyllosticta theae. Pink disease Corticium salmonicolor. Poria root rot and stem canker Poria hypobrunnea. Purple root rot Helicobasidium compactum. Red leaf spot Phoma theicola. Red root rot Ganoderma philippii Poria hypolateritia [1] = Ceriporiopsis hypolateritia [1] Red rust (alga) [2] Cephaleuros ...
The lesions continue to grow, and by the end of summer form leaf spots that look like tar. [2] The spot can grow up to 1.5 inches (4 cm) in diameter. [4] A microscopic sign of the pathogen are the stroma, mats of hyphae found in the lesions. [2] These lesions can cause senescence of leaves but are mostly of cosmetic importance.