Exploring genotype × environment interaction for chickpea grain yield and related traits by a mixed model approach

Abstract

Abstract The study of genotype × environment interaction is crucial for plant breeding to introduce new cultivars with im-proved yield and stable performance. The productivity of chickpea crops is very low in Pakistan, requiring the se-lection of genotypes with optimal productivity for diverse environmental conditions. Fourteen different chickpea genotypes were assessed using the linear mixed model to evaluate genotypes across four diverse chickpea growing regions, including Attock (Punjab), Bhakkar (Punjab), Karak (Khyber Pakhtunkhwa), and Larkana during 2017-19. The environmental effect was very pronounced, contributing significantly to variation (25.8%) in grain yield. Analysing genotype × environmental interaction at multiple locations facilitates ranking superior genotypes that excel in specific or diverse environments. Notably, the genotypes viz. Fakhr-e-Thal and Bhak-kar-2011 demonstrated superior performance in terms of overall grain yield. Utilising a multi-trait stability index, Bittal-2016 and Thal-2006 emerged as the most stable genotypes across various environments, suggesting their suitability for diverse growing regions. On the other hand, for specific environmental conditions, genotypes KK-1, Noor-2013 and Fakhr e thal exhibited high yields but low stability, showcasing their adaptability to a particular environment. The The analysis revealed that Larkana is a mega environment conducive to higher yield, while At-tock, Bhakkar, and Karak were identified as less favorable for KK-3, DG-89, and Dasht. The findings hold signif-icant implications for expediting chickpea breeding efforts to improve the genotypic plasticity and understanding correlation patterns among traits to confer climatic resilience. Finding high-yielding, stable genotypes and their representative environment offers new breeding opportunities and boosts production for chickpea cultivars.