猪粪沼液施用对稻、麦产量和氮磷吸收的影响

在江苏太湖稻麦轮作区,开展了连续2年不同沼液替代化肥比例及沼液基追比的等氮田间试验,结果表明:单施化肥处理(NPK)及沼液化肥配施处理水稻、小麦生物量及产量均显著高于无肥对照,各处理以75％沼液替代比例分3次施入(N75％)处理的水稻生物量和产量为最高,其生物量及产量分别比单施化肥处理提高2.7％和7.5％；而小麦生物量和产量以50％沼液替代比例(N50％)处理最高,其生物量和产量比单施化肥处理分别提高15.9％和7.8％.沼液化肥配施对稻麦的增产作用主要体现在提高水稻与小麦总穗数及穗粒数上；各处理水稻、小麦的氮素累积量和氮素当季表观利用率分别以75％(N75％)和50％(N50％)替代比例为最高；在50％～ 100％替代比例内沼液分次施用,水稻、小麦氮肥农学效率、偏生产力都高于化肥处理.水稻、小麦不同器官的氮分配比例显示,沼液配施化肥促进氮素向籽粒转移；相同沼液替代比例下,沼液分次施用水稻、小麦的产量、氮素累积量及氮素利用率均较基肥一次性施入高.稻、麦根、叶部磷含量分别以N75％和N100％处理最高.以上表明稻麦配施50％ ～ 75％的沼液分3次施用,可获得与纯化肥处理相当的产量,且在一定程度上提高稻麦氮素利用率.

Effects of Digested Pig Slurry Application on Yields, Nitrogen and Phosphorous Uptakes by Rice and Wheat

A two-year field experiment under rice/wheat rotation system in Tai Lake region in Jiangsu Province of China was carried out to study the effect of digested pig slurry (DPS) on yields and nitrogen use efficiency of rice and wheat. The results showed that the treatments of pure chemical fertilizer (NPK) application and combined use of chemical fertilizer and DPS obtained significantly higher biomass and grain yields of rice and wheat than the no fertilizer control (CK). The treatment of N75% (75% N substituted) and N split application had the highest rice biomass and yield, which were 2.7% and 7.5% higher than the NPK treatment, respectively. The highest wheat biomass and yield, which were 15.9% and 7.8% higher than the NPK treatment, was found in the treatment of N50% (50% N substituted). The increased yields of rice and yield by combined use of DPS and inorganic fertilizer were mainly attributed to the increased numbers of panicle and filled grain. The highest N accumulations and N recovery efficiencies (NREs) of rice and wheat occurred in the treatments of N75% and N50% (50% N substituted), respectively. In the range of 50%-100% N substitution combined with N split application, both agronomic nitrogen use efficiency and partial factor of productivity of N fertilizer of rice and wheat were higher than the NPK treatment. N distribution proportion between different rice and wheat organs showed that combined use of DPS and inorganic fertilizer promoted N transfer into grains. Within the same substitution ratio, split application of DPS enhanced the grain yield, N accumulation and N use efficiency of rice and wheat than base application. The highest P contents in roots and leaves of rice and wheat appeared in the treatments of N75% and N100%, respectively. The best N substitution ratios of between 50% and 75% by DPS for rice and wheat could promote crop growth and N uptake and split fertilization was more suitable than base fertilization when DPS and chemical fertilizers were combined use in rice and wheat.