Parametric stability analysis of durum wheat yield (triticum durum desf)

Abstract

We evaluated the phenotypic stability of 23 durum wheat genotypes using various stability parameters to select genotypes that have both high performance and stability. The research was conducted in four locations by randomized complete block design with four replications in each location during the 2008-09 and 2009-10 cropping seasons. The objectives were to assess genotype-environment interactions (GEI), determine stable genotypes, and compare the mean grain yield with the stability parameters. To quantify yield stability, seven stability statistics were calculated (bi, Pi, ASVi, CVi, S 2 di, S 2 i and W 2 i). The grain yields of all genotypes were significantly affected by environment, which accounted for 88.2 % of the total variation, whereas genotype and genotype-environment interaction accounted for 2.9 % and 8.9 %, respectively. The genotype mean yield significantly positively correlated with the regression coefficient (bi) and environmental variance (S 2 i). The correlation analysis also separated the Pi, bi and S 2 i methods, which correlated with the mean yield, and the ASV, W 2 i and S 2 di methods, where the phenotypic stability seems to be measured independently on the yield. Genotypes Bel, Amg, Miki, Bss and Msb were more stable by most statistics used. Miki, Amg and Msb were the best genotypes demonstrating high average yields and high stability of performance across the test locations.