平衡施肥对高粱产量·效益及养分收支平衡的影响

目的]探寻适合山西省中部高粱生产的最佳施肥方案。方法]采用随机区组设计,设置不同施肥水平,研究平衡施肥对高粱产量、效益及养分收支平衡的影响。结果]平衡施肥对高粱产量和效益有明显的正效应。农民习惯施肥处理较推荐施肥处理减产6.3%,收入减少376.05元/hm~2。氮肥是影响当地高粱高产的主要限制因子,其次为磷肥和钾肥。平衡施肥有利于高粱植株对养分的均衡吸收,与农民习惯施肥处理相比,推荐施肥处理的高粱氮、磷、钾吸收量平均增加了17.52、3.68、32.46 kg/hm~2。225.00 kg/hm~2的氮肥投入量基本能满足当地高粱高产的需求,75.00 kg/hm~2的磷肥投入量高于需求量,而钾肥用量不足。氮、磷、钾肥利用率分别为25.0%、16.3%和55.8%。结论]从土壤养分收支平衡及肥料利用率方面考虑,应该在推荐施肥处理基础上适当提高钾肥用量,减少磷肥用量,促使施肥方案不断优化,达到高粱的高产、高效目的。

Effect of Balanced Fertilization on Yield,Economic Benefits of Sorghum and Nutrient Balance

Objective] To explore the optimal fertilization scheme for sorghum in central Shanxi Province.Methods] Randomized block design was adopted and different fertilization levels were arranged . Results] Balanced fertilization exerted significant positive effect on yield and benefit of sorghum.In comparison, farmers’ conventional fertilization treatment suffered yield drop for 6.3% and income reduction of 376.05 yuan/hm2 .Nitrogen fertilizer was the major restricting factor influencing yield of local sorghum , followed by phosphorus and potash fertilizer . Balanced fertilization is favorable for uniform absorption of nutrients .Compared with conventional fertilization treatment , the recommended treat-ment of N, P and K fertilizer increased about 17.52, 3.68, and 32.46 kg/hm2 .225.00 kg/hm2 nitrogen fertilizer basically could meet demands of high yield of local sorghum, 75.00 kg/hm2 phosphorus fertilizer input was higher than the demand, while the potash fertilizer application was not sufficient.The utilization efficiency of N, P, and K fertilizer was 25.0%, 16.4% and 55.8%respectively.Conclusions] It is required to increase the application of K fertilizer on the basis of recommended application , reduce P fertilizer, and promote optimization of fertilization and reach the objective of high yield and benefit.