Grey Mildew : A Perilous Disease For Cotton Crop
Cotton, a principal cash crop touches India’s economy at several points. An estimated 60 million people are dependent for their livelihood, either by its cultivation, marketing, processing, export, textile manufacturing or by extraction of seed oil and production of ‘Vanaspati’. In recent years with increasing International demand and domestic consumption, cotton productivity, fibre quality improvement, as well as resistance breeding against insect pests and diseases, have become more mission-oriented. Among the various diseases of cotton, grey mildew disease is gaining more importance in recent years because of its increasing incidence.
Symptoms Of Grey Mildew:
The disease usually appears on the undersurface of the bottom leaves when the crop is nearing maturity. Irregular to angular pale translucent lesions which measure 1-10 mm (usually 3-4 mm) develop on the lower surface, usually bound by veinlets. On the upper surface, the lesions appear as light green or yellow-green specks. A frosty or whitish-grey powdery growth, consisting of conidiophores of the fungus, appears on the lower surface. When several spots coalesce, the entire leaf surface is covered by white to grey powdery growth. White or grey powdery growth may occur on the upper surface also. The infection spreads to upper leaves and the entire plant may be affected. The affected leaves dry up from margin, cup inward; turn yellowish-brown and fall off prematurely.
Favourable Conditions for grey mildew:
The pathogen survives during the summer in the infected crop residues. The perennial cotton plants and self-sown cotton plants also harbour the pathogen during summer months. The primary infection is through conidia from infected plant debris and secondary spread is through the wind, rain splash, irrigation water and implements.
Management For Grey Mildew In cotton :
Grey mildew has become a Matter of concern for every cotton grower. Every time they think that how can they protect their crop from this perilous disease. For Management of grey Mildew Hpm chemicals and Fertilizers presents Bhoomiputra ( A Systemic Fungicide ). It is a systemic, preventive and curative fungicide for control of a range of fungal leaf diseases in crops. It has preventative, antisporulant and early curative action with leaf disease control. It shows rapid translocation and inhibits spore germination and reduce spread. It Gives Best Result when it is applied to actively growing cotton in fine weather at least 2 hours before the rain. Ensure thorough coverage of leaves and stems. Apply at first sign of disease or as a protectant when disease risk is high. Use mixed spray within 24 hours. Application to stressed cotton may give unreliable results. Use Bhoomiputra with a different mode of action as follow up sprays.