Evaluation of Gamma Irradiation on Cotton Genotypes Fruiting Parts and Infestation of Spotted Bollworm, Earias Vittella (Fab.)

Abstract

Research trial was carried out in the fields of Agriculture Research Institute, Tandojam during 2008 and 2009. The effects of gamma (“Gy” 150, 200 and 250) were evaluated on six cotton genotypes i.e. St-7, BNT, B-3, SB, SP and B-4. The data were recorded on mean number of fruiting bodies; squares, flowers, green bolls setting and spotted bollworm damage percent on square, flowers and green bolls. Results revealed that the gamma irradiated genotypes were significantly effective when compared to untreated cotton genotypes. The highest mean number of squares was found in mutant genotype SP* (200 Gy) and (250 Gy), during both years. The maximum mean number of flowers was observed in B-4* and SP*, with (200 Gy) during 2008 and 2009. In the year 2008 higher mean numbers of green bolls were found in B-4* with (150 Gy) and BNT with (250 Gy). While in year 2009 B-4* (150 Gy) and BNT with (250 Gy). The comparative infestation of spotted bollworms E. vittella on squares, flowers and green bolls in cotton genotypes indicated high resistance, moderate susceptibility and high susceptibility in untreated and gamma irradiated strains during above of mentioned period. Results showed that there were significant differences between untreated parent and their gamma irradiated cotton genotypes bearing fruiting bodies and pest infestation