秸秆还田条件水肥耦合对水稻产量与品质的影响

Effects of water-fertilizer coupling with straw returning on yield and quality of rice

为了研究秸秆还田条件水肥耦合对水稻产量与品质的影响,采用盆栽试验对土壤水分、施氮量、秸秆还田量采用正交处理,同时设置重复3组,其中对照1组.试验结果表明:水分与肥料的投入量对水稻产量影响较大,在适宜的用量范围内,水稻产量与灌水量、氮肥施用量、秸秆还田量呈正相关关系;当超出适宜用量范围后,随着氮肥施用量及秸秆还田量的持续增加,水稻产量并没有提高,而是出现一定程度的降低;水稻产量在氮肥施用量270 kg/hm^2、正常灌溉处理、秸秆还田量4 200 kg/hm^2情况下达到最高.水稻籽粒蛋白质受氮肥施用量及灌溉水量影响也相对较大,在氮肥施用量324 kg/hm^2、分蘖后期水分胁迫、秸秆还田量为4 200 kg/hm^2情况下,水稻籽粒蛋白质含量达到最高.

In order to study effects of water-fertilizer coupling on yield and quality of rice under straw returning condition, pot experiments were conducted based on three factors such as soil moisture（water stress in late rice tillering, water stress in late tillering and grain-filling, normal water treatment）, nitrogen application rate and straw returning rate by employing orthogonal experiment method, and at the same time, three groups were designed, including one control group. The results show that soil moisture and nitrogen application rate as well as straw returning rate have a greater impact on rice yield. Within the allowable range, the rice yield increases with increasing irrigation water, straw returning rate and nitrogen application rate. However, beyond the range, with increasing straw returning rate and nitrogen application rate, the yield doesn′t rise but exhibits a reduction in some degree.Intere- stingly , when nitrogen application rate is 270 kg/hm^2, soil moisture is in normal water treatment and straw returning rate is 4 200 kg/hm^2, the rice yield reaches the highest value. Nitrogen application rate and soil moisture also affect protein content of rice grain. When nitrogen application rate is 324 kg/hm^2, water stress is in late-tillering and straw returning rate is 4 200 kg/hm^2, the protein content of rice grain arrives at the maximum.