Screening of drought-tolerant rice landraces using various drought indices in Nepal

Drought-resilient varieties are of great significance in the context of climate change and the increasing frequency of droughts. This study evaluated the drought tolerance in twelve rice landraces from three distinct agro-climatic zones (Tarai, Inner-Tarai, and Mid-Hill) in Far-west Nepal. The landraces were subjected to control, intermittent drought, and complete drought treatments to assess their yield and drought tolerance indices. The yield reductions were observed across all varieties. Based on the generalized linear model (GLM), varieties like Chamade, Ratomarso, Jhumke from Mid-Hill, Jhini, Shanti from Inner-Tarai, Lalchand and Anjana varieties from Tarai have significantly higher yield loss. Varieties like Temase, Chiudi, Batebudo, Sauthyari and Ghiupuri have less yield reduction than the baseline mean of the studied system i.e., 15.9%. Drought tolerance indices effectively differentiated landrace responses. Ghiupuri, Lalchand, and Sauthyari exhibited superior tolerance based on consistently higher index values. Principal component analysis and cluster analysis revealed distinct patterns of response among landraces, highlighting the importance of considering multiple traits and employing multivariate methods for comprehensive drought tolerance evaluation and selection of resilient varieties for water-scarce environments. By identifying drought-tolerant landraces, this research supports sustainable agriculture and food security, aligning with Sustainable Development Goals 2 (Zero Hunger), 13 (Climate Action), and 15 (Life on Land) by promoting climate-resilient crop production and biodiversity conservation.