Genotype X environment interaction and yield stability of finger millet (Elusin Corcana L.) genotypes based on AMMI, GGE and MTSI analysis in humid lowland areas of Ethiopia

Abstract

The yield and agronomic performance of finger millet (Eleusine coracana L.) are influenced by genotype-by-environment interactions, necessitating multi-environment testing to identify superior genotypes. The objective of this study was to identify finger millet genotypes that exhibit high yields and stability across various environmental conditions, as well as to determine the environments that best promote high trait expression. Eleven finger millet genotypes were evaluated using a randomized-complete-block design with three replications in subsequent four main seasons from 2015 to 2018 totaling eight test environments at the two different environments of Ethiopia viz, at Manbuk and Dibate. Following the detection of significant GEI interaction for the studied traits, the stability of finger millet genotypes was assessed by using AMMI, GGE biplot, and multi-trait stability index (MTSI) methods. The study has effectively and conveniently aided in deciphering of genotype-environment interaction and for the identification of stable and superior genotypes and ideal environments using AMMI and GGE analyses based on grain yield data. The estimation of stability indices, WAASB (Weighted Average of Absolute Scores from the singular value decomposition of the BLUP matrix) and WAASBY (a combination of stability and mean yield), was emphasized for identifying genotypes with more stability and greater yield potential. The study demonstrated the suitability of MTSI which computes the genotype-ideotype distance while considering a number of traits. The AMMI, GGE biplot, and MTSI methods examined were concordant in the identification of finger millet genotypes that not only exhibit high performance but also demonstrate stability across a diverse range of environmental conditions. These methods proved effective in recognizing those genotypes that can maintain their superior performance even when faced with varying environmental factors, ensuring reliable results in different settings.