About the Disease: The powdery mild dew infects all kinds of cucurbits. It is a fungal disease.
Symptoms: The main symptom that is seen is the pale yellow colored spots that are found all over the surface of the leaves. These spots then get converted to large blotches. This will be covering the total stretch of the leaf. These blotches will also be covering the regions of the stem and the petiole. The whole foliage is covered with the infected fungal spores. The fruits will ripen before the actual time.
Pathogens: Podosphaera xanthii is the main causative agent. Humid conditions are needed for the infection to occur.
Time of Occurrence: This mainly occurs in the humid conditions. When the weather is warm and dry, this is the best condition for the development of the new fungal spores. Then the disease easily spreads from one plant to another. The old leaves or the mature ones are more prone to be attacked by the fungal disease than the young leaves.
Conditions Favoring Disease: The temperature that can easily favor the growth of the fungus and the progression of the disease is around 68 to 81 F.
Disease Management: The most sensible way to control the disease is by using the resistant varieties. Thus when you plan to cultivate the crops, you must choose healthy ones as well as those varieties that are less susceptible to this disease. Thus either a partially resistant or a completely resistant plant can be grown. The application of good fungicides that does not destroy the other neighboring crops is a good option. The recommended dosage of the fungicide ahs to be applies, so that the entire plant does not get killed.
There is a special guide for the Midwest vegetable production. This guide can be read and understood to gain more information on how to prevent tor manage the disease in the crop fields. For the protection of both the upper and the lower parts of the leaf, sulfur powder can be applied. Some soil test can also be done. This might help in understanding the deficiencies in soil. If the plants are overcrowded in the field, then there are chances for the occurrence of this disease. Thus overcrowding has to be surely avoided.
Before planting them, a thorough research on the total area available and the way to plant the crops without cramping them, has to be done. On each week, the mature leaves have to be thoroughly examined, to find out if there are symptoms of the infection on the plants.