Submergence tolerance of selected Sri Lankan traditional rice (oryza sativa L) accessions at seedling stage

Abstract

Micro climate of Sri Lankan rice fields varies significantly due to intermittent flooding and drying caused by changing pattern of climate. As traditional rice posse considerable biotic and abiotic stress tolerant traits, present study was carried out to screen out the selected traditional rice accessions for their submergence tolerance at the seedling stage. The experiment was conducted as randomized complete block design with four replicates and 10 plants per each replicate. Two weeks old rice seedlings were subjected to 09-day and 14-day complete submergence stress while the control was kept without submergence. Plants were evaluated after 2-week recovery period under de-submerged conditions. Submergence tolerance and mode of tolerance were identified as the survival rate and elongation/suppression respectively. Data were analyzed by ANOVA using SAS software. A significantly highest survival percentage was recorded by Hondarawala-4243 t80%l while Kalukondq-S4gT was the second best (37.5%), and Kalu wee-4541, and Goda heenati-3724 scored the third highest survival rate (17.5 Vo) under complete submergence stress of 14-day. Survived and susceptible accessions followed both modes of survival; quiescence and elongation. The findings of the present study can be utilized for further research purposes or breeding programs in rice improvement.