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Phytophthora Blight

About the Disease: This disease will be infected crops like peppers, the eggplants and tomatoes. It can also affect some variety of beans. The cucurbit crops will be mainly affected.

Symptoms: There will be many irregular and giant spots, all over the surface of the leaves in the plants. The leaf petiole will have many lesions. The stem will also be seen with many lesions. Those fruits that are infected will be very soft. It will be fully covered with some white colored powder. This refers to the fungus growth on the fruits.

Pathogens: Phytophthora capsici is the main pathogen that is involved in causing the disease.

Time of Occurrence: During the late summer, you can expect to see the plants to get affected by this disease.

Conditions Favoring Disease: When the weather is a little wet as well as cool, it seems to be a favorable condition for the progression of the disease. The main mode of dispersal of the fungal spores is through the wind or water. There can be so many resilient spores that still thrive in the soil. There will be an indefinite count of such spores. Thus you can never predict the extent to which the crops or the yield can get affected in one season. There can also be some amount of infested residue of the infected crops.

Disease Management: Usually the resistant varieties can be grown to avoid the disease. In the pumpkin and squash plants, there are less number of resistant varieties. Thus you cannot find many pumpkin plants that are resistant to Phytophthora blight. But in the pepper plants, you can find some resistant plants. Apart from this disease management strategy, you can also use some protective fungicides. For instance, you can use the fungicides like Mancozeb or chlorothalonil.

One of the metals that can help in the process of reducing the progression of the disease is copper. There will be a great yield loss due to the fungi. This can be greatly used on application of copper. The method of crop rotation can help in preventing the disease. If you cultivate the cucumber for the first few months, then you can cultivate squash for another five months. After this period, the cucumber can be grown again. In this way there will not be a continuous chance for the multiplication of the disease. Another simple way of avoiding this disease is by preventing water logging. Stagnation of water in the crop fields will further enhance the efficiency of the application of these fungicides.