Stability of some of rice genotypes based on WAASB and MTSI indices

Ten rice genotypes were evaluated in a randomized complete block design with four replications in three regions of Iran during three cropping seasons. Likelihood ratio test (LRT) was shown the significant effects of genotype and genotype by environment interaction (GEI). Scree plot indicated the first three components explained ۸۱.۲۴% of GEI variation. Mosaic plot partitioned total sum of squares (TSS) and indicated genotype and GEI effects illustrated ۵۲.۷۲% and ۴۷.۲۸% of TSS, respectively. Heatmap plot also exhibited variations in the grain yield of genotypes across environments. The best linear unbiased predictors (BLUPs) of grain yield showed that G۲, G۵, G۴, G۱۰ and G۶ had a higher prediction than the overall grain yield. The nominal yield plot indicated G۴, G۵, G۶ and G۱۰ had a small contribution in GEI and were more stable genotypes. In the fourth quarter of grain yield vs the weighted average of absolute scores (WAASB) biplot, G۲, G۵ and G۱۰ were highly productive and stable. Based on a weight of ۵۰:۵۰ for grain yield and stability, G۵, G۶, G۲, and G۳ had the highest WAASBY values and were determined as stable genotypes. In WAASB/GY ratio plot, it is observed that G۵, G۶, G۲, and G۳ had the highest WAASBY values and were deyermined as stable genotypes. Factor analysis based on WAASBY values of all of the traits identified three factors with a cumulative variance of ۷۹.۳۵. Based on the multi-trait stability index (MTSI), G۶ and G۳ were selected. In conclusion, G۵ was superior to all genotypes and can be used to determine the best cropping manangement in agronomic research experiments and for the introduction of new cultivars.

Keywords:

AMMI , BLUP , Factor analysis , Heatmap , Mosaic plot