Flash flood or submergence is a common phenomenon in rice growing rainfed lowland areas that seriously affects crop establishment leading to severe yield losses. A few submergence-tolerant rice varieties have been dev...Flash flood or submergence is a common phenomenon in rice growing rainfed lowland areas that seriously affects crop establishment leading to severe yield losses. A few submergence-tolerant rice varieties have been developed by introgressing SUB1 gene into mega rice varieties of South Asia. Two of these, Swarna-Sub1 and Sambha Mahsuri-Sub1, are already released in India for the commercial cultivation. Performance of these varieties can be further enhanced through adoption of appropriate management practices both in nursery and in main field. Two on-station field experiments were conducted using Swarna-Sub1 during the wet season (kharif) of 2011 at Rice Research Station, Chinsurah, Hooghly, West Bengal (India). Results of these experiments revealed that the use of lower seeding density (25 g m-2), application of balanced doses of N-P2O5-K2O @ 80-40-40 kg ha-1 in nursery and transplanting of aged seedlings (44 days) significantly improved plant survival, yield attributing traits and grain yield. An additional N-dose of 20 kg ha-1 at 7 days after receding of flood water resulted in better post-submergence recovery and maximum grain yield. In the on-farm trials conducted at three different locations in West Bengal, nursery raising of seedlings with the application of N-P2O5-K2O @ 80-40-40 kg ha-1, transplanting them at an optimum age (35 days) and application of 20 kg·N ha-1 after 7 days of de-submergence produced maximum grain yield of Swarna-Sub1.展开更多
文摘Flash flood or submergence is a common phenomenon in rice growing rainfed lowland areas that seriously affects crop establishment leading to severe yield losses. A few submergence-tolerant rice varieties have been developed by introgressing SUB1 gene into mega rice varieties of South Asia. Two of these, Swarna-Sub1 and Sambha Mahsuri-Sub1, are already released in India for the commercial cultivation. Performance of these varieties can be further enhanced through adoption of appropriate management practices both in nursery and in main field. Two on-station field experiments were conducted using Swarna-Sub1 during the wet season (kharif) of 2011 at Rice Research Station, Chinsurah, Hooghly, West Bengal (India). Results of these experiments revealed that the use of lower seeding density (25 g m-2), application of balanced doses of N-P2O5-K2O @ 80-40-40 kg ha-1 in nursery and transplanting of aged seedlings (44 days) significantly improved plant survival, yield attributing traits and grain yield. An additional N-dose of 20 kg ha-1 at 7 days after receding of flood water resulted in better post-submergence recovery and maximum grain yield. In the on-farm trials conducted at three different locations in West Bengal, nursery raising of seedlings with the application of N-P2O5-K2O @ 80-40-40 kg ha-1, transplanting them at an optimum age (35 days) and application of 20 kg·N ha-1 after 7 days of de-submergence produced maximum grain yield of Swarna-Sub1.
