Epidemiological studies on Cotton Leaf Curl Disease on non transgenic genotypes in relation to environmental conditions

Abstract

Studies were conducted on Cotton leaf curl disease (CLCuD) in relations to environmental conditions. Three non-transgenic genotypes viz. CIM-554, CIM-591 and CIM-608.were planted with 15 days intervals from 15th  April to 15th June. Generally, 15th April planting showed significantly less disease incidence than all other sowing dates. The incidence increased as the sowing was delayed up to 15th June. The CLCuD boost up within 90 to 120 days after planting, regardless of sowing date and genotypes. The disease incidence increased gradually while CIM-554 gave maximum disease incidence than all other strains. The cultivars CIM-591 and CIM-554 showed no effect on the reduction of disease index on any planting dates, but however the strain CIM-608 showed some tolerance against the disease when planted on 15th  April- 1st  May. The maximum, 34.8~38.6°C, minimum 28.8~30.2°C temperature and relative humidity 67.8~75.4% favored CLCuD progression.