控释尿素对水稻产量及氮肥利用率的影响

Effect of Controlled Release Urea Fertilizer on Rice Yield and Nitrogen Utilization Efficiency

为了探讨等量氮素用量(N 180 kg/hm^2)条件下,控释尿素对水稻产量及氮肥利用率的提高效应,通过田间试验,比较分析了控释尿素和普通尿素在不同施用量下对水稻产量及氮肥利用率的影响。结果表明,控释尿素全量处理的产量最高,两试验点产量分别为8 977.5 kg/hm^2(罗山)和8 986.5 kg/hm^2(固始),较同等氮素用量的普通尿素全量处理增产4.40%、4.42%,差异达显著水平。控释尿素全量的3/4处理和1/2产量处理均与普通尿素全量处理之间差异不显著。这说明与普通尿素相比,控释尿素减少1/4~1/2的氮素用量时也能达到同样的产量水平。氮肥利用率以控释尿素全量的1/2处理最高,两试验点分别为66.5%和68.3%,较同等氮素用量的普通尿素全量的1/2处理提高19.2、20.6个百分点。同时,控释尿素还可明显降低水稻土壤中硝态氮的含量。综合产量和氮肥利用率,以控释尿素全量的3/4(N 135 kg/hm^2)处理最优。

In order to discuss the enhancing effect of controlled release urea（ CRU） on rice yield and nitrogen utilization efficiency under the condition of equal amount of nitrogen fertilizer,the effects of CRU and common urea（ CU） under different dose on rice yield and nitrogen utilization efficiency were studied.The results showed that the highest yield of rice was 8 977. 5 kg/ha（ Luoshan county） and 8 986. 5 kg/ha（ Gushi county） in the treatment with 100% CRU. Compared with the equal amount treatment with 100%CU,the yield of the treatment with 100% CRU significantly enhanced by 4. 40%（ Luoshan county） and 4. 42%（ Gushi county）,respectively. There were no significant differences of rice yields between the treatments with 3/4CRU,1/2CRU and the treatment with 100% CU,which showed that CRU with subtracting 1/4—1/2 nitrogen application amount could achieve the same yield compared with CU. The highest nitrogen utilization efficiency was 66. 5%（ Luoshan county） and 68. 3%（ Gushi county） in the treatment with 1/2CRU,which increased by 19. 2（ Luoshan county） and 20. 6（ Gushi county） percentage points compared with the equal nitrogen application amount treatment with 1/2CU,respectively.Meanwhile,CRU could reduce NO-3-N accumulation in soil significantly. In summary,the treatment with 3/4CRU was optimal,according to rice yield and nitrogen utilization efficiency.