Abstract

                                An experiment was conducted to study the effect of gossypol gland density in different plant parts in relation to bollworm incidence (Helicoverpa armigera) and seed cotton yield in 10 bollworm donor lines and their 45 F1's obtained in 10 x 10 diallel fashion (without reciprocals). A wide range of variability was observed for gossypol gland number, size and volume per unit arca on leaf, bract and calyx surfaces both in parents and hybrids. The present study revealed that both in parents and hybrids, the nature of relationship between gland density in different plant parts and bollworm incidence in reproductive parts did not follow similar trend. The study also revealed the scope for utilisation of high gossypol gland density on leaf, bract and calyx in future breeding programmes for development of high yielding cotton cultivars with inbuilt mechanism for bollworm tolerance especially for H. armigera.

Key words : Gossypol gland. Bollworm and American cotton