Combining ability estimates for seed cotton yield and quality characters of parents and crosses based on genetic male sterility in Asiatic cotton (Gossypium arboreum L.)

Abstract

Fourteen parents and 40 F1 crosses (genetic male sterility based) were evaluated in a line x tester fashion in Asiatic cotton (Gossypium arboreum). The statistical analysis was performed using the method developed by Kempthorne (1957) with the help of OPSTAT computer program (developed by CCS Haryana Agricultural University, Hisar. Sufficient variability among hybrids and their parents was found as the mean squares of genotypes for all the traits including fibre quality were significant. The variance due to GCA was lower than SCA for boll number per plant, boll weight and GOT. For other traits like seed cotton yield, fibre length, micronaire value and strength, the SCA was higher which reflected the role of both additive and non-additive types of gene action (dominant or epistatic). GCA was significant for male parents CISA-6-165, CISA-6-187, CISA-6-209, CISA-6-295, CISA-6-350, CISA 7, CISA 8 and female parents CISA 2, DS 5, GAK 413A for seed cotton yield. Parents CISA-6-123, CISA-6-165, CISA-6-350, CISA 8, CISA 9, GAK 413A, CISG 20 showed significant GCA for fibre length and CISA-6-123, CISA-6-350, CISA 8 for micronaire value. Among 40 cross combinations, SCA was positively significant for seed cotton yield in 5 crosses, for boll number in 16 crosses, for boll weight in 9 crosses and for fibre length and micronaire in 16 crosses.

Keywords

• cotton
• combining ability
• seed cotton yield
• genetic male sterility
• fibre quality