Cotton is an important fiber cash crop of India and cotton leaf curl disease is the major biotic constraint that can significantly reduce the production and productivity of the crop. Gossypium hirsutum L. suffered losses in Northern part of India mainly in Haryana due to high incidence of cotton leaf curl disease (CLCuD) and “whitefly” which is the vector of this disease. Development of resistant variety to this disease is most effective, long term and safe method to tackle with this problem. First step in this direction is screening and identification of resistant sources and their incorporation in the agronomical superior genotypes/varieties. | Study of genetic diversity in upland cotton (Gossypium hirsutum L.) of cotton leaf curl disease resistant and susceptible genotypes by using ISSRS