Evaluation of Secondary Traits as Indicators of Drought Tolerance in Rice

Rice is susceptible to various abiotic stressors, including drought, heavy metals, salt, cold, and submergence. This research was conducted to evaluate the secondary traits of six rice varieties as indicators of drought tolerance. It was conducted from February 19 to July 6, 2024, in Paddaoan, Conner, Apayao, utilizing a factorial setup within a Randomized Complete Block Design composed of two water conditions (well-irrigated and water-stressed) applied to six varieties: PSB Rc10, NSIC Rc160, NSIC Rc506, NSIC Rc508, Mestizo 20, and Mestizo 73. This study focused on the identification of rice genotypes that are relatively higher yielding under drought condition as well as determination of the relationship between yield attributes and yield. Results showed that well-irrigated conditions significantly affected all parameters, with unstressed plants surpassing their stressed counterparts. Among the varieties, NSIC Rc160, NSIC Rc508, and Mestizo 73 shown exceptional performance in growth, fertility, and yield, especially under non-stress settings, with NSIC Rc160 achieving the highest metrics. In contrast, PSB Rc10 consistently exhibited the least favorable performance in both treatments, signifying inadequate drought adaption. Notable genotype-by-treatment interactions were recorded, underscoring varied varietal responses to drought. The research underscores the necessity of advancing drought-resistant cultivars for sustainable rice cultivation and advocates for the utilization of high-yielding genotypes in both irrigated and rainfed regions. Further study across many places and seasons is advised to validate these findings.