摘要
【目的】我国化肥过量施用现象普遍,不利于生态环境保护和农业可持续生产。研究化肥减量施用对小麦产量、籽粒灌浆和肥料利用率的影响,可以为我国化肥高效施用和零增长目标提供理论依据。【方法】在四川盆地进行了两个大田试验,以习惯施肥(N、P_2O_5、K_2O分别为180、120、45 kg/hm^2)为对照,设置减量施肥(N、P_2O_5、K_2O分别为96、60、45 kg/hm^2)处理,测定了小麦产量及构成、籽粒灌浆、花后干物质转运、旗叶叶绿素含量、养分平衡和肥料利用率。【结果】与习惯施肥相比,减量施肥下小麦产量、穗数、穗粒数没有显著变化,小麦–玉米轮作田块小麦千粒重显著提高5.8%。根据Logistics方程拟合结果,减量施肥显著提高了小麦–玉米轮作田块小麦理论最大千粒重,渐增期、缓增期籽粒净增重,对其他灌浆参数影响不显著。减量施肥下小麦干物质转运量、转运率及其对籽粒灌浆的贡献率增加28.5%、17.5%和20.7%,但花后旗叶叶绿素含量下降速度加快。习惯施肥和减量施肥土壤氮素盈余分别为22.6和–30.2 kg/hm^2,土壤磷盈余分别为80.4和22.8kg/hm^2。减量施肥后氮肥偏生产力、农学效率和表观回收率比习惯施肥提高79.2%、69.1%和27.9%,磷肥偏生产力、农学效率和表观回收率提高91.1%、72.7%和68.5%。【结论】本试验的两年时间内,减量施肥可以维持小麦产量,促进小麦干物质转运及其对籽粒灌浆的贡献,但花后功能叶衰退加速。减量施肥下肥料利用率提高,土壤磷素盈余降低,土壤氮素亏缺,需要在确保维持小麦产量、土壤肥力和养分平衡的基础上,继续优化减氮量。
[ Objectives ] Excessive chemical fertilizer application is unfavorable for sustainable agricultural development. It is important to conduct optimize fertilization experiment for achieving fertilizer zero increase in China. [ Methods ] Two on-farm experiments were conducted in wheat-corn and wheat-rice rotation systems in a purple soil in the Sichuan Basin, southwest China. Taken conventional N, P205, K20 input of 180, 120, 45 kg/hm2 as control, reduced fertilizer rate （N, P2O5, K^2 input of 96, 60, 45 kg/hm2） in wheat was applied. The wheat yield and its components, grain filling characteristics, translocation of dry matter and chlorophyll contents of flag leaves at the post-anthesis, nutrient balance and use efficiency were investigated. [ Results ] Compared with conventional fertilizer rate, wheat yield, the numbers of spikes, grains per spike and 1000-grain weight were not significantly changed under reduced fertilizer rate, expect for the 1000-grain weight in fields of wheat-maize cropping system. Based on the Logistic simulation model for the grain filling, the reduced fertilizer rate treatment significantly enhanced the maximum 1000-grain weight, the net increase of grain weight during the gradual and slow grain-filling periods, but not significant on other parameters. Reduced fertilizer rate increased the dry matter translocation, efficiency and contribution to grain by 28.5%, 17.5% and 20.7%, respectively, but accelerated the decline of chlorophyll in wheat flag leaves after flowering. Under conventional fertilizer rate, the soil N and P had surplus of 22.6 and 80.4 kg/hm2, respectively; under reduced rate soil N had a deficit of 30.2 kg/hm2, but still had a surplus P of 22.8 kg/hm2. The respective nutrient use efficiencies indicated by the partial factor productivity, agronomic efficiencies and apparent recovery efficiencies were significantly improved by 79.2%, 69.1% and 27.9% for the N fertilizer, and 91.1%, 72.7% and 68.5% for the P fertilizer. [ Conclusions ] In Sichuan Basin, the reduced fertilizer rate maintained the wheat yield, improved the nutrient use efficiencies, P balance, efficient translocation of dry matter and contribution to grain filling, but caused the deterioration of flag leaves and the soil N loss, which might result in a fertility decline especially in a long-term period due to an insufficiency under the current reduction rate of N fertilizers. Therefore, rational N fertilization rate needs to be further optimized in the future.
作者
赵亚南
宿敏敏
吕阳
况福虹
陈轩敬
张跃强
石孝均
ZHAO Ya-nan SU Min-min LU Yang KUANG Fu-hong CHEN Xuan-jing ZHANG Yue-qiang SHI Xiao-jun(College of Resources and Environment, Southwest University, Chongqing 400716, China College of Resources and Environment, China Agricultural University, Beijing 100093, China National Monitoring Station of Soil Fertility and Fertilizer Efficiency on Purple Soils, Chongqing 400716, China)
出处
《植物营养与肥料学报》
CAS
CSCD
北大核心
2017年第4期864-873,共10页
Journal of Plant Nutrition and Fertilizers
基金
国家自然科学基金项目(31471944)
中央高校学科团队项目基金(2362015xk06)
中央高校基本业务费专项资金(XDJK2016E156)资助
关键词
小麦产量
籽粒灌浆
干物质转运
肥料利用率
养分平衡
wheat yield
grain filling
dry matter translocation
nutrient use efficiency
nutrient balance
