Climate resilient breeding for high yields and stable wheat (Triticum aestivum L.) lines under irrigated and abiotic stress environments
Radhakrishna Bhandari, Harikala Paudel, Shivalal Nyaupane, Mukti Ram Poudel
Abstract
Wheat has a crucial role in eradicating all forms of hunger and malnutrition worldwide to achieve the target set by Sustainable Development Goal 2.0. The potentiality of wheat to eradicate hunger and malnutrition is severely limited by abiotic stresses such as heat stress and drought. To evaluate the performance, stability and to visualize the interrelationship among morphological parameters of wheat genotypes in order to identify the most appropriate trait for climate resilient breeding, a field experiment was conducted in the western region of Nepal during 2021-22 and 2022-23 under irrigated (I), heat stress (HS), and heat drought (HD) environments. The additive main effect multiplicative interaction (AMMI) model ANOVA showed environment had the most substantial effect on the expression of all the traits studied (p≤0.001). Wheat yield was reduced by 24 and 48% under HS and HD environments. BL 4919 (4609.5 kg ha−1), BL 4919 (3037.6 kg ha−1), and Bhrikuti (2228.9 kg ha−1) were the highest-yielding genotypes across irrigated, heat stress, and heat drought environments, respectively. WWW model revealed NL 1369, NL 1404, and NL 1417 were the most adaptable wheat genotypes across irrigated, heat stress, and heat drought environments, respectively. Whereas, NL 1381 was the most stable genotype. Phenotypic correlation, path analysis, and principal component analysis (PCA) revealed, high yielding genotypes can be selected via days to booting (DTB), days to heading (DTH), days to anthesis (DTA), booting-heading duration (BtoH), booting-anthesis duration (BtoA), and plant height (Ph). For climate resilient breeding program traits such as earliness, longer booting-heading and booting-anthesis duration, shorter heading-anthesis duration should be promoted. Dwarf genotypes might be productive under irrigated environments and taller genotypes should be promoted under heat stress and heat drought environment.