硫膜和树脂膜控释尿素对水稻产量、光合特性及氮肥利用率的影响

本试验以控释期为90d的硫膜（SPCU）和树脂膜（PCU）控释尿素为材料，通过盆栽试验，研究了硫膜和树脂膜控释尿素对水稻产量、 光合特性及氮肥利用效率的影响。结果表明，与普通尿素（U）一次基施相比，控释尿素各处理均能显著提高水稻子粒产量、 氮肥表观利用率和农学效率，增幅分别达15.1%~51.4%、 64.5%~14.11%和5.4~18.2 kg/kg；显著提高水稻生育中后期叶片净光合速率；提高水稻生育中后期的SPAD值。与普通尿素分次施用相比，树脂膜控释尿素及硫膜控释尿素和普通尿素以7∶3比例一次性施入的处理能显著提高水稻子粒产量、 氮肥农学效率以及水稻收获后的土壤全氮和碱解氮含量，其增幅分别为7.9%~31.7%、 3.3~13.0 kg/kg、 2.2%~17.6%和13.2%~22.0%；显著提高叶片中后期的净光合速率，且以树脂膜控释尿素100%一次基施的处理最高。施用树脂膜控释尿素的各处理较普通尿素均能显著提高水稻的氮肥生理效率。树脂膜控释尿素比硫膜控释尿素表现出更好的水稻增产效应和氮肥利用效率，更能有效延缓叶片衰老，实现水稻氮素的高效利用。

Effects of sulfur-and polymer-coated controlled release urea on yield,photosynthetic characteristics and nitrogen fertilizer efficiency of rice

Using sulfur- and polymer-coated controlled release urea with a releasing period of 90 days as experimental materials, a pot experiment was conducted to study the effects of sulfur- and polymer-coated controlled release urea on yield and photosynthetic characteristics and nitrogen fertilizer efficiency of rice. Compared with the conventional urea, the controlled release urea significantly increases the grain yields by 15.1%51.4%, and increases the nitrogen apparent efficiencies and nitrogen agronomic efficiencies by 63.3%139.9% and 5.418.2 kg/kg, respectively. The controlled release urea could greatly improve the net photosynthetic rate in flat leaves of rice and enhance SPAD during the middle-late growth stages. Compared with the conventional urea split, the polymer-coated controlled release urea and the 70% sulfur-coated controlled release urea combined with 30% conventional urea markedly increase the grain yields by 7.9%31.7%, and the nitrogen agronomic efficiencies and soil total N and available N are increased by 3.313.0 kg/kg and 2.2%17.6% and 13.2%22.0%, respectively, and the net photosynthetic rate in flat leaves at the middle-late growth stages are also significantly increased. The effect of the 100% polymer-coated controlled release urea is most important. Compared with the conventional urea and the conventional urea split, the polymer-coated controlled release urea could significantly increase nitrogen fertilizer physiological efficiency of rice. The polymer-coated controlled release urea produces better rice yield and has higher nitrogen fertilizer efficiency and effective photosynthetic characteristics, compared with the sulfur-coated controlled release urea.