Identification of superior parental lines for seed quality and storability through GGE biplot analysis of line x tester data in grain sorghum

Identification of superior parental lines and their hybrid combinations for seed quality traits pave the way for enhancement of crop stand and yield per se. A line x tester analysis was carried out using GGE biplot to identify best combiners for seed quality and storability in 6 A and 9 R grain sorghum lines. ANOVA showed significant effects of lines, testers and their interactions for all the traits. L2 (296A) proved to be a poor combiner for all the traits both in fresh (FS) and aged seeds (AS), while L1 (2219A) was the best combiner for germination (G) and field emergence (FE) in FS, and L6 (IMS 9A) for seedling vigour index (SVI) of FS. 'Which-won-where' analysis proved that L1 (2219A) gave the best or near the best cross combination with all testers for G-FS, G-AS, FE-FS and FE-AS. L6 (IMS 9A) combined well with majority of testers for SVI-FS and SVI-AS. It was observed that the SCA effect of lines which come out in 'mean-versus-stability' analysis may not necessarily identity lines with SCA in favorable direction. Polygon view gives a better visualization of the heterotic pattern. T6 (C43) proved to be the best tester for G-FS and G-AS, and was near ideal tester for all other traits except for SVI-FS. For SVI-AS, T1 (CS 3541) proved to be better than T6 (C 43). Among all testers T3 (RS 29) was relatively less informative for being non-discriminatory or non-representative in most of the cases.