Study of Genetic Erosion, Variation and Correlation among Morpho-Physiological Traits of Ahu Rice of Assam, India

Abstract

The conservation of traditional rice landraces, along with their associated farming practices and indigenous knowledge, plays a vital role in ensuring long-term food security. However, the progressive disappearance of these landraces from cultivation has not been adequately addressed by researchers. This study examines genetic erosion, variability, and trait relationships among 12 traditional ahu rice varieties cultivated by Mising tribal farmers in Assam's Jorhat and Golaghat districts. The results demonstrate a concerning decline in landrace diversity, highlighting the risk of genetic erosion. Statistical analysis revealed significant differences among the varieties for most measured traits, with the exception of radicle length, leaf area index, photosynthetic rate, and stomatal conductance. The recently introduced Kolong variety achieved the highest grain yield, along with superior performance in filled grains per panicle and total spikelets per panicle. Genetic analysis showed considerable heritable variation in chlorophyll stability index, while days to 50% flowering exhibited strong genetic control. Grain yield displayed significant positive correlations with tiller density, panicle density, spikelet number per panicle, filled grain count, and spikelet fertility at both genetic and observable levels. These findings underscore the critical need to preserve traditional ahu rice varieties to mitigate genetic erosion while incorporating high-performing cultivars into farming systems. Coordinated efforts involving farmers, policymakers, and researchers are necessary to maintain agricultural biodiversity and secure future food production.