THE EVALUATION ON RECOVERY PHASE OF POST-SUBMERGED RICE

Rice plants may experience submergence stress in various phases of plant development due to the unpredictable flash flooding occurred during planting season. Plants’ recovery phase after submergence is an important phase that determines plant survival. The character of plant growth and development during this recovery phase can be important information in determining the tolerance of plants to submerged stress. Therefore, this study was conducted to evaluate the recovery phase of post-submerged rice plants indicated by the character of plant growth and development. Split plot design was utilized with rice cultivars as the main plot and submergence time subplot. Two cultivars used were IR 42 (non-tolerant cultivar) and Inpari 30 (tolerant cultivar), while submergence time consisted of three phases, namely: 1) generative initial phase = 42 days after transplanting (DAT); 2) active tillering phase = 28 DAT, and 3) early vegetative phase = 7 DAT. Plant samplings were conducted for six times: right before submergence (t0), right after submergence (t1), 4 days after submergence (t2), 7 days after submergence (t3), 10 days after submergence (t4) and 14 days after submergence (t5). Results showed that both cultivar and submergence time showed a non-significant effect on plant growth during recovery phase, except for leaf greenness parameter. The recovery pattern of rice plants after experiencing submergence stress was generally not influenced by the age of the plants during stress. In addition, improvements in plant growth characters began to appear after 10 days of recovery.