G x E interaction studies in multi-location trials of sugarcane using GGE Biplot and ANOM analysis

Abstract

In the process of release of new cultivars using multi-location data, while major emphasis is being laid on superiority of the new cultivars over the ruling cultivars, less importance is being given to genotype × environment (GxE) interaction. The aim of this study was to exploit analysis of genotype and genotype x environment interaction(GGE), its magnitude and significance using analysis of mean (ANOM) which graphically presents the nature of G x E and stability of advanced stage cultivars evaluated in multi-location trials. Data on sucrose, commercial cane sugar %, cane and sugar yields of 14 early clones and three standards from three crops/seasons (2006-2009) and four locations Coimbatore and Pugalur (Tamil Nadu state), Sankeshwar (Karnataka state) and Padegaon (Maharashtra state) of Peninsular India were analyzed. ANOM studies helped in easy assessment of the sugarcane genotypes for cane yield and sugar yield under four environments and three crop seasons. Significant genotypic differences and G x E interaction influenced the relative ranking of hybrids across environments. ANOM indicated positive interaction effects for cane yield and sugar yield in Co 0209, Co 0312 and Co 0314. GGE (PC1 and PC2) captured 64.0, 60.7, 49.1 and 49.6% of the total variation for sugar yield, cane yield, CCS% and sucrose% respectively. Among the genotypes, Co 0312, Co 0314 and Co 0209 were the top yielders. Co 0312 was identified as the most stable and ideal genotype with high cane and sugar yields, and sucrose % suggesting the potential of this early clone as an alternative to CoC 671. Being the closest to the ideal genotype, Co 0314 was a good candidate when selected specifically for cane and sugar yield. In order to sustain future gains, use of Co 0312 and Co 0314 as alternate checks in clonal evaluation trials is suggested. The high yielding and stable genotypes identified can be exploited as donors in breeding program. The results were compared with two stability assessment methods and the genotypes Co 0312 and Co 0314 with regression coefficient ‘b’ values near to unity for cane yield and, deviation from regression coefficient (S2d) values of 0.722 and 0.700 respectively were identified stable,in accordancewith ANOM results.