on cucumber and muskmelon is caused by the fungus Pseudoperonospora cubensis. Irregularly shaped yellowish to brown spots appear on upper sides of leaves, usually at the center of plants. Under moist conditions, a purplish mildew develops on the underside of leaf spots. Leaves die as spots increase in size. Spread is rapid from the crown toward new growth. The causal fungus overwinters in areas with a relatively warm climate and can be introduced to other areas by wind. Moist conditions favor disease development.
caused by Cercospora citrullina, affects cantaloupe and watermelon. Leaf spots are small, dark brown to black with a white center, and may have a yellow halo.
کلمات کلیدی: پاورپوینت آماده بررسی بيماريهاي خیار cucumber به زبان انگلیسی پاورپوینت آماده تحقیق درسی پاورپوینت آماده