Cotton Section, Department of Plant Breeding, CCS Haryana Agricultural University, Hisar-125 004, India.
Abstracts of the papers presented at the 16th Annual Convention and International Symposium of Indian Virological Society on “Management of Vector-Borne Viruses” at International Crops Research Institute for the Semi-Arid Tropics (ICRISAT), Patancheru-502324, Hyderabad, India, February 7–10, 2006.
In North India, among all the diseases, the disease caused by Cotton leaf curl virus (CLCuV) alone is capable of causing 10–75 per cent of losses in yield of seed cotton. Whitefly transmitted geminivirus was first reported on Gossypium hirsutum near Sriganganagar in Rajasthan 1993 and in Haryana during the next crop season has spread to all the major cotton growing area and became a threat to cotton cultivation in this region. The disease can be managed by various methods like clean cultivation in and around cotton field, management of Bemisia tabaci (vector) from early stage. Viruliferous whitefly require very short period to transmit the CLCuV, therefore, common insecticides are not effective in controlling the disease. The genetic resistance is thus the best effective, economical and ecofriendly management method and is possible only by the development of resistant varieties/hybrids. The knowledge of source of resistance is must to carry out systematic breeding programme to incorporate resistant gene in promising genotypes. A total number of 938 cotton germplasm lines were screened against CLCuV disease during 2004–05 crop season at different stages of plant growth i.e. vegetative phase, reproductive phase and at maturity. 477 entries were found resistant against CLCuV disease under natural epiphytotic field conditions. These entries can be further used as a source of resistance for the development of disease resistant varieties.
