机插秧单季晚稻中沼液的施用技术研究

摘要

研究了沼液用量和施用时期不同比例对机插秧单季晚稻产量、品质和土壤肥力的影响.结果表明,沼液施用量对水稻产量有显著的影响,但施用时期的沼液配比对产量的影响不明显.沼液具有显著促进水稻分蘖、增加有效穗和每穗粒数的作用,但施用过量则会影响稻米品质;施用沼液可增加稻米中镉、铅等重金属的积累,但其含量均在安全食用标准内.施用沼液可使土壤肥力质量略有下降.沼液的适宜施用量为15.5～27.7 t·667m-2(折合纯氮11.5～20.7 kg·667m-2),施用比例以3-3-2-2和4-2-3-1为妥.%An orthogonal experiment, including three treatments of biogas slurry application rate and three combinations of biogas slurry application time, was carried out to study the effects of biogas slurry application rate and time on yield and quality of machine-transplanted single cropping late rice as well as soil fertility.The results showed that application rate of biogas slurry showed a significant effect on yield of single cropping late rice, but combinations of biogas slurry application time showed no significant effect on rice yield.Application of biogas slurry could significantly improve tillering, and increase earbearing percentage, productive panicle number and spikelet number per panicle.However, over-application of biogas slurry could impact the quality of brown rice.Application of biogas slurry slightly increased the concentrations of Cd and Pb in the grains, but the concentrations of heavy metals in the grain for all treatments were lower than their safety limits.As compared with chemical fertilizer, application of biogas slurry could slightly decrease the quality of soil fertility.It was suggested that the optimum rate of biogas slurry application ranged from 15.5 to 27.7 t· 667m -2 ( equivalent N of 11.5 ～ 20.7 kg·667m -2 ), and optimum combinations of biogas slurry application time was 3 - 3 - 2 - 2 and 4 - 2 - 3 - 1.