Performance and Stability of some Bread Wheat Genotypes across Terminal Water and Heat Stresses Combinations Using Biplot Techniques

Abstract

The current study was conducted at Shandaweel Agric. Res. Stat., Agric. Res. Center, Egypt. Eighteen bread wheat genotypes were grown under four treatments during 2018/19 and 2019/20 seasons. The treatments were (1) normal conditions (sowing on 25th November and 5 irrigations). (2) Terminal water stress conditions (sowing on 25th November and 3 irrigations). (3) Terminal heat stress conditions (sowing on 25th December and 4 irrigations). (4) Combined stresses (sowing on 25th December and 3 irrigations). The combined analysis of variance showed significant differences between the genotypes, treatment, seasons for all the studied traits. The mean performance of the genotypes showed that L11 was the highest grain yield and grain filling rate under normal, water stress, heat stress, combined stresses as well as overall treatments. Genotype by genotype-environment biplot (GGE biplot) illustrated that the best performing genotype under normal conditions was Baj 1 while Shandaweel 1 was the best performing genotype under stress combinations. Genotype x trait biplot (GT biplot) showed a positive correlation between all the traits except, days to heading and days to maturity. Genotype by yield*trait biplot (GY*T biplot) was constructed to estimate superiority and stability for the genotypes. GY*T biplot showed a positive correlation between all yield*trait combinations. Based on superiority index (SI), the best performing genotypes was L11 (SI = 1.830) and the worst was L7 (SI = 1.935). L11 genotype can be utilized in breeding program as a source for abiotic stresses tolerance or can be evaluated in preliminary yield trials at the national level.