Study of the Impact of climatic Factors on the Progression of Powdery Mildew on Okra incited by Erysiphe cichoracearum DC and Evaluation of the Effectiveness of Chemical Salts in Its Control

Abstract

One of the major vegetable crops, Okra, is a member of the Malvaceae family. Among the diseases, one of the most dangerous fungal diseases that severely reduces yield is powdery mildew, which is brought on by Erysiphe cichoracearum DC. During meteorological weeks 49, 2, and 3, the projected and observed PDI values were nearly equal. Between the 52nd and 1st week, the maximum apparent rate of infection (r) of 0.0758 was recorded; this value was comparable to the "r" value between the 3rd and 4th week. The crop is sensitive to powdery mildew at stage 60 DAS, with a maximum PDI of 64.65%. This is because nutrients are translocated from the source to the sink in later stages of the plant's life, rendering it susceptible. When the amount of chlorophyll in various disease-grade leaves is estimated, it is found that leaves with mildewed 0-scale content have larger amounts of chlorophyll "a," chlorophyll "b," and total chlorophyll, at 0.230, 0.083, and 0.327 mg/g, respectively, while leaves with mildewed 5-scale content have the lowest amounts.