【摘要】 研究不同氮用量对冷浸田水稻氮钾吸收利用和产量的影响,探求在冷浸田水稻氮肥适宜用量;以D优202水稻品种为材料,田间试验研究6个不同氮量(0、45、90、135、180、225 kg hm-2)下水稻含氮量、含钾量、氮和钾的积累量以及产量的差异及其相互关系。在冷浸田开沟降渍的条件下,在0~225 kg hm-2纯氮范围内,随氮肥水平的增加,水稻含氮量在有效分蘖临界叶龄期、拔节期、抽穗期均显著增加,成熟期先增后减,含钾量除有效分蘖临界叶龄期外其他时期均显著降低,含氮量相应提高含钾量会有所降低;植株氮和钾的积累量基本具有相同的趋势,先增加后减少。分析表明:水稻各个生育阶段的氮、钾与稻谷产量均呈正相关,增施氮肥有利于水稻氮和钾吸收利用的提高,但氮肥过高时氮和钾吸收利用不再增加,甚至有所降低。在磷钾一定的条件下,冷浸田水稻最高产量施氮量为169.0 kg hm-2,经济施氮量为153.9 kg hm-2。更多还原

【Abstract】 Understanding the effects of different nitrogen rates on the absorption and utilization and yield of rice nitrogen and potassium in cold waterlogged paddy fields, and exploring the optimal N rate in the cold waterlogged paddy fields, the rice varieties of D You 202 was taken and studied on the rice nitrogen content, potassium content, nitrogen and potassium accumulation and yield difference and their mutual relations by means of field experiments with six different nitrogen contents(0, 45, 90, 135, 180 and 225 kg hm-2). In the condition of trenching and reducing immersing in cold waterlogged paddy fields, rice nitrogen content significantly increased during the critical stage of tillering, elongation stage and heading stage with the increase of nitrogen fertilizer which was within the pure nitrogen range of 0- 225 kg hm-2, while it in mature stage first increased and then decreased. Rice potassium content decreased in all other stages except the critical stage of tillering, with a trend of potassium decreasing by increasing nitrogen. The accumulative nitrogen and potassium in plant in all stage had the same trend basically, that was first increased and then decreased. The analysis results showed that there was a positive correlationship related to nitrogen fertilization between nitrogen or potassium and rice yield during every growth stages, consequently, increasing application of nitrogen fertilizer was benefit for absorption and utilization of rice nitrogen and potassium, but when addition of overhigh nitrogen fertilizer, the absorption and utilization for nitrogen and potassium of rice would not increase, even decrease. Under the certain phosphorus and potassium condition, the application rate of nitrogen would be 169.0 kg hm-2, and economic nitrogen rate would be 153.9 kg hm-2, in order to reach the highest rice yield in cold waterlogged paddy fields.更多还原