|
| Synergistic effects of source-sink characteristics on CH4 emissions from paddy fields under different nitrogen application rates and panicle removal treatments |
| Received:December 08, 2023 |
| View Full Text View/Add Comment Download reader |
| KeyWord:paddy field;CH4 emission;nitrogen application rate;panicle removal;source-sink characteristic;root exudate |
| Author Name | Affiliation | E-mail | | HUANG Yuqing | National Key Laboratory of Crop Genetic Improvement/Key Laboratory of Crop Ecophysiology and Farming System in the Middle Reaches of the Yangtze River, Ministry of Agriculture and Rural Affairs/College of Plant Science and Technology, Huazhong Agricultural University, Wuhan 430070 | | | REN Xiaojian | National Key Laboratory of Crop Genetic Improvement/Key Laboratory of Crop Ecophysiology and Farming System in the Middle Reaches of the Yangtze River, Ministry of Agriculture and Rural Affairs/College of Plant Science and Technology, Huazhong Agricultural University, Wuhan 430070 | | | ZHANG Qingshuang | National Key Laboratory of Crop Genetic Improvement/Key Laboratory of Crop Ecophysiology and Farming System in the Middle Reaches of the Yangtze River, Ministry of Agriculture and Rural Affairs/College of Plant Science and Technology, Huazhong Agricultural University, Wuhan 430070 | | | ZHOU Jiyong | Wuxue Agro-Technology Extension Service Center, Wuxue 435499, China | | | XIONG Dongliang | National Key Laboratory of Crop Genetic Improvement/Key Laboratory of Crop Ecophysiology and Farming System in the Middle Reaches of the Yangtze River, Ministry of Agriculture and Rural Affairs/College of Plant Science and Technology, Huazhong Agricultural University, Wuhan 430070 | | | CUI Kehui | National Key Laboratory of Crop Genetic Improvement/Key Laboratory of Crop Ecophysiology and Farming System in the Middle Reaches of the Yangtze River, Ministry of Agriculture and Rural Affairs/College of Plant Science and Technology, Huazhong Agricultural University, Wuhan 430070 | cuikehui@mail.hzau.edu.cn |
|
| Hits: 1088 |
| Download times: 1101 |
| Abstract: |
| To elucidate the relationship between the source-sink characteristics of rice plants and CH4 emissions from paddy fields, a study was conducted using three nitrogen application rates of 0N（no nitrogen application）, 150N（S0）（150 kg·hm-2, no panicle removal）, and 210N（210 kg·hm-2）, and a half-panicle removal treatment under 150N treatment, under field conditions. CH4 emissions from paddy fields, total organic carbon, and carbohydrate content in root exudates, and source-sink size and grain yield were measured. The results indicated that compared with 210N, 150N（S0）significantly increased the spikelet number per unit area by 6.7% and the sink capacity by 6.6%, while panicle removal resulted in a 55.9% decrease in both the spikelet number per unit area and the sink capacity. Sink characteristics under different treatments significantly influenced rice yield and CH4 emissions from paddy fields. Compared with 210N, 150N（S0） significantly decreased the cumulative CH4 emissions by 29.5% and increased the yield by 7.2%. Panicle removal resulted in a 53.0% decrease in yield and a 76.8% increase in cumulative CH4 emissions. The cumulative CH4 emissions and the yield-scaled CH4 emissions were significantly and negatively correlated with sink capacity, spikelet number per unit area, grain-leaf ratio, and rice yield, respectively. Compared with 210N, 150N（S0）decreased the total organic carbon and carbohydrates in root exudates by 18.9% and 39.7%, respectively; while compared with no panicle removal, panicle removal significantly increased the total organic carbon and carbohydrate contents in root exudates by 65.8% and 217.1%, respectively. The cumulative CH4 emissions and the yield-scaled CH4 emissions were significantly and positively correlated with the total organic carbon and carbohydrate content in root exudates. Additionally, the total organic carbon and carbohydrate contents in root exudates were significantly and negatively correlated with the spikelet number per unit area, sink capacity, and grain yield. This study indicated that the characteristics of rice sink under different treatments mainly affect CH 4 emissions through root exudates. Therefore, moderate nitrogen application rates can increase rice sink capacity and reduce root organic carbon exudation, thereby reducing CH4 emissions from paddy fields while achieving higher rice yields. |
|
|
|
