Application of GGE-Biplot Analysis to Multi-environment Screening of Sugarcane in Central and Western Regions in Thailand

Abstract

GGE-biplot analyses were applied to multi-environment trials of sugarcane, at 22 locations in 11 provinces in central and western Thailand, using 12 genotypes in 3 crop cycles (newly planted, first-ratoon and second-ratoon crops). The objectives of the present study were to evaluate the use of the GGE-biplot method to analyze the effects of genotype (G) and genotype-environment interaction (GE) in sugarcane breeding, to identify the representative locations for reducing the number of test environments and to classify the sugarcane genotypes based on their adaptation to several environment groups. The largest variations were found for the crop-cycle in all the traits, and the location also showed large variations. The variations from crop-cycle, location and location x crop-cycle interaction were more important than that of genotype, although the effects of the genotype and related interactions were significant. In the GGL (Genotype x Genotype-Location) biplots, the coordinates and vectors of locations and genotypes clearly explained the associations among them, suggesting that the biplot technique was highly effective to reveal the relationships among tested locations and genotypes. Regarding sugar yield, 4 groups of locations were classified in these regions. In the future experiments, the sugarcane breeders may be able to reduce the number of test locations to these 4 representative environments without substantial loss of information about the genotypes. K90-77 was classified into a generally adapted genotype, whereas the genotypes K88-92 and UT5 were specifically adapted to the central and western regions of Thailand.