Efficiency of Parametric and Non Parametric Indices as the Indicators of Grain Yield Stability of Bread Wheat (Triticum aestivum L.) Genotypes under Rainfall Conditions

Abstract

Background: Under rainfall conditions, grain yield stability is one of the most important objectives of breeding programs, especially in diverse environments. Under such conditions, stability analysis offers the best solution for the relative performance of genotypes over environments. The aims of this study are the selection of adapted and stable bread wheat genotypes based on the using of some parametric and non-parametric index. Methods: The experiment was conducted during the four consecutive agricultural seasons (2016/17-2017/18, 2018/19 and 2019/20) at the level of the experimental station of Setif (ITGC). Eight (08) genotypes of bread wheat were tested in this study. To calculate the parametric and non-parametric indices, we use the STABILITYSOFT program. Result: The association between Wricke’s ecovalence (Wi²), the mean variance component (θᵢ) and the Stability variance (σ²ᵢ) indices with the grain yield proved that the best genotypes for growing under these conditions are G1, G2, Hidhab, Arz, Wifak and Ain Abid. In addition, the selection based on the non-parametric index and the combination selection based on highest grain yield with the parametric and non parametric indices proved that the genotypes G1, G2 and Wifak are the more stable and adapted genotypes under semi-arid conditions. In addition, based on the static and dynamic concepts, the parametric indices bi and CVi are related to the dynamic concept, while the other indices are associated with static stability concept. Overall, the results of this study confirmed that the parametric and Non-parametric methods are the suitable tools to identify the most stable bread wheat genotypes at various environmental conditions.