控失尿素对水旱轮作下水稻产量和氮素利用效率的影响

摘要

为探究控失尿素对水旱轮作下水稻产量及土壤肥力的影响,采用大田小区试验,研究了控失尿素减量和普通尿素不同配比混施对水稻产量、氮肥利用率及土壤养分残留量的影响.结果表明,普通尿素和控失尿素均能显著提高水稻叶片叶绿素含量、株高和生物量,但两处理之间无显著差异.控失尿素增产效果低于普通尿素,主要是由于水稻有效穗数的降低.控失尿素和普通尿素混施比单施控失尿素增产0.51~0.92 t/hm2.在不同配比中,控失/普通为7:3处理更有利于水稻生长,具有较高的株高、生物量以及氮肥利用效率和较低的氮素残留,增产效果较好.控失尿素减量10%和20%都会显著降低水稻叶片叶绿素含量和肥料利用率,且分别减产0.24~0.41和0.39~0.51 t/hm2.%In order to study the effect of controlled release urea on yield and nitrogen use efficiency, two field experiments were conducted to examine the rice yield, nitrogen use efficiency and soil nutrient residues under different combination of common urea and controlled release urea. The results showed that controlled release urea and common urea both significantly improved the chlorophyll content, plant height and biomass of rice, but there was no significant difference between these two treatments. The increase in rice yield under controlled release urea was lower than that under common urea, mainly due to the decrease of the number of effective panicles of rice. The combination of common urea and controlled release urea increased rice yield by 0.51~0.92 t/hm2than single application of controlled release urea. In different ratios of common urea and controlled release urea, the treatment of controlled release urea/common urea=7:3 was most conducive to rice growth, with the highest plant height, biomass and nitrogen use efficiency, lowest nitrogen residue and highest yield. The treatment of decreased nitrogen by 10% or 20%, significantly decreased chlorophyll content of rice leaves, nitrogen utilization efficiency, and reduced rice yields by 0.24 to 0.41 t/hm2and 0.39 to 0.51 t/hm2, respectively.