Genotype x environment interaction and genotype evaluation for yield, yield components and qualities in sugarcane (Saccharum Spp.), Ethiopia

Abstract

The presence of genotype x environment interaction (GEI) and the limited knowledge on the relationships among production environments complicate selection of superior varieties in sugarcane. For this reason, studying about the nature of GEI, genotype evaluation and classification of the production environments in to distinct mega environments is very important in sugarcane breeding program. The study was conducted to investigate the nature of genotype x environment interaction, classify environments in to mega environments and evaluate genotypes based on yield performance and stability. Forty-three genotypes along with six standard varieties were evaluated across location and over crop years using simple lattice design. Data of cane yield, cane yield components and yield qualities were subjected to analysis of variance (ANOVA). Results from ANOVA declared the importance of GEI under Ethiopian agro climatic conditions. When the data was analyzed using the GE model, the f-values were inflated and the genetic variation was under estimated. Thus, for multi-environment trials conducted across locations and over seasons, data analysis based on the GLC model would be appropriate. The genotype + genotype x environment interaction (GGE) bi-plots divided the target environment in to distinct mega environments where a repeatable genotype x location interaction was observed for recoverable sucrose% and sugar yields. Moreover, GGE bi-plots identified introduced genotypes that have better broad and specific adaptations than the commercial varieties and can be commercially exploited according to their respective regional niche. Moreover, we recommend a breeding strategy for specific adaptation in future sugarcane breeding programs in Ethiopia.