Foot rot incidence in Kinnow orchards and its management through biorational paint formulations

Abstract

The prevalence of citrus Phytophthora in Kinnow orchards varied from 3.7-21.4% in Sriganganagar district situated in North-West part of Rajasthan. Old Kinnow orchards in high cropping intensity area with heavy soils exhibited comparatively high incidence of foot rot disease. Field studies were conducted to find out environmentally accepted paint formulation, alternate to metalaxyl for the control of foot rot disease in Kinnow. Stem painting with metalaxyl (Ridomil MZ 72 WP) @ 20 g/l linseed oil, talc based Pseudomonas fluorescence (2 × 109 cfu/g) or Trichoderma harzianum (2 × 107 cfu/g) @ 100 g/l water subsequently painting with linseed oil after 5 days each during February and August was found significantly superior over check and other paint formulations in giving maximum per cent recovery in trunk lesion size of Phytophthora rot of Kinnow. The per cent increase in yield under these treatments ranged between 98.73 - 87.93 per cent. Paint formulations involving tulsi (Ocimum sanctum L.) leaf powder and bulb extract of garlic (Allium sativum L.) @ 100 g/l linseed oil and T. harzianum formulation @ 100 g/l rice starch solution were found at par in controlling Phytophthora disease. The Kinnow plants painted with turmeric powder (Curcuma longa L.) @ 100 g/l linseed oil and untreated plants (control) enhanced trunk lesion size and yield under these treatments decreased to the extent of 29.26 and 78.54 per cent, respectively.