不同施肥措施对水稻光合参数、氮素利用效率和产量的影响

Effects of Different Fertilization Practices on Photosynthetic Parameters, Nitrogen Use Efficiency and Yield of Rice

摘要:

为了探讨缓控释肥与追施尿素对水稻光合参数、氮磷钾积累量和产量及构成因素的影响，以临稻16为材料，在大田总施氮量284 kg/hm²条件下，设传统施肥，水稻免追控释肥及磷钾肥基施，基施复合肥+分蘖期、幼穗分化期追施2次尿素，基施复合肥及磷钾肥+返青期、分蘖期、幼穗分化期追施3次尿素共4个处理，研究缓控释肥及追施氮肥对水稻光合参数、产量构成及经济效益的影响。结果表明，与传统施肥相比，缓控释肥及追施氮肥显著提高了水稻光合特性，如净光合速率、气孔导度、蒸腾速率等。基施缓控释肥处理平均穗粒数最多，为142粒；相比于农民传统施肥，基施缓控释肥处理增产10.3%，分2次追施尿素处理增产13.5%，分3次追施尿素处理增产16.3%。综合不同施肥模式的经济效益，基施缓控释肥处理经济效益表现最高，每hm²收益较分2次和3次追施氮肥处理增加3.7%以上，施用缓控释肥是促进水稻增产、农民增收的有效措施。

Abstract:

This study investigated the effects of slow- and controlled-release fertilizers and urea topdressing on the photosynthetic parameters, nitrogen, phosphorus and potassium accumulation, yield components and economic returns of rice. Lindao 16 was used as the test cultivar in a field experiment with a total nitrogen application rate of 284 kg/ha. Four fertilization treatments were established: A, conventional farmer fertilization; B, basal application of controlled-release fertilizer and phosphorus and potassium fertilizers without topdressing; C, basal application of compound fertilizer with urea topdressing at the tillering and panicle differentiation stages; and D, basal application of compound fertilizer and phosphorus and potassium fertilizers with urea topdressing at the regreening, tillering, and panicle differentiation stages. The results showed that, compared with conventional fertilization, the application of slow- and controlled-release fertilizer and staged nitrogen topdressing significantly improved the photosynthetic characteristics of rice, including net photosynthetic rate, stomatal conductance and transpiration rate. The treatment with basal application of controlled-release fertilizer produced the highest average number of grains per panicle, reaching 142 grains. Compared with conventional farmer fertilization, grain yield increased by 10.3% under treatment B, 13.5% under treatment C, and 16.3% under treatment D. Among the different fertilization practices, treatment B, involving basal application of controlled-release fertilizer, produced the highest economic returns, which were more than 3.7% higher per hectare than those under the treatments involving two or three applications of nitrogen fertilizer. Therefore, the application of slow- and controlled-release fertilizer is an effective measure for increasing rice yield and farmers’income.