摘要
【目的】通过田间试验探究黄土旱塬氮肥施用和地膜覆盖对春玉米干物质累积、产量和氮素吸收利用的影响。【方法】田间试验于2016年和2017年在中国科学院水利部水土保持研究所长武黄土高原农业生态试验站进行。该站位于陕西省咸阳市长武县洪家镇,地貌为高原沟壑区,地带性土壤为黑垆土,供试作物为春玉米。试验采用裂区设计,主区为地膜覆盖和不覆盖,副区为4个施氮水平(0、100、250和400 kg/hm^2)。在玉米六叶期(V6)、十叶期(V10)、吐丝期(R1)、乳熟期(R3)及完熟期(R6) 5个时期采集植株样品,测定生物量并按照需要分为不同部位测定植株全氮含量。【结果】1)氮肥施用和地膜覆盖显著提高春玉米籽粒产量,地膜覆盖条件下氮肥提高春玉米籽粒产量效果更显著。地膜覆盖条件下施氮量250 kg/hm^2和400 kg/hm^2处理春玉米籽粒获得高产,产量达12.8～16.4 t/hm^2,两个施氮量间春玉米籽粒产量差异不显著;不覆盖条件下,施氮量400kg/hm^2处理春玉米籽粒产量显著低于250 kg/hm^2处理。2)氮肥施用和地膜覆盖及二因素互作显著提高春玉米花前和花后氮素累积量,二因素互作对春玉米花后氮素和干物质累积作用较花前更大,地膜覆盖条件下施氮处理花后氮素和干物质累积量比例分别为51.5%～54.9%和51.1%～59.9%,为春玉米籽粒产量提高奠定物质基础,地膜覆盖条件下施氮量250 kg/hm^2和400 kg/hm^2处理可获得高的花前和花后氮素和干物质累积量,但施氮量400 kg/hm^2处理的氮素和干物质累积量与施氮量250 kg/hm^2处理的均差异不显著。3)由于氮肥施用和地膜覆盖互作显著提高花前氮素累积和促进花后的生长发育,二因素协同促进春玉米营养器官氮素转移量,地膜覆盖条件下施氮量250 kg/hm^2和400 kg/hm^2处理均能有效促进花前储存更多的氮素向籽粒转运,提高花后期氮同化量,促进籽粒产量的提高。相同覆盖条件下,施氮量400 kg/hm^2处理营养器官氮素转移量与施氮量250 kg/hm^2差异不显著。4)地膜覆盖显著提高相同施氮量下氮肥农学效率和氮肥偏生产力;地膜覆盖和氮肥用量及二因素互作显著提高氮收获指数,地膜覆盖条件下,施氮量250 kg/hm^2和400 kg/hm^2处理可获得较高的氮收获指数,氮收获指数达65.1%～75.4%,但施氮量250 kg/hm^2和400 kg/hm^2处理氮收获指数差异不显著。【结论】在该试验条件下,氮肥施用和地膜覆盖互作显著提高春玉米花前和花后的氮素吸收和干物质累积,但二因素互作对春玉米花后氮素吸收和干物质累积影响更大,从而促进了营养器官氮素转移,提高了春玉米产量和氮收获指数。
【Objectives】This experiment is to investigate the effect of nitrogen(N)application and plastic film mulching on dry matter accumulation,yield and N uptake and utilization of spring maize.【Methods】A field experiment was conducted from 2016 to 2017 in the Changwu County,Xianyang City,Shaanxi Province,which belonged to typical gully region of the Loess Plateau with the dark loessial soil.A split design was applied for the experiment,the main factors included plastic film mulching(FM)and no mulching(NM),and the sub-factors included four different N application rates of 0,100,250 and 400 kg/hm^2.Plant samples for measuring total biomass were collected at different growth stages,6 expanded leaves(V6),10 expanded leaves(V10),silking stage,milking ripening and entire ripening stage.The samples were divided into different parts as required,and the total N contents were determined.【Results】1)Both N application and plastic film mulching significantly increased grain yield of spring maize.N application improved the yield of spring maize more effectively under plastic film mulching.High grain yields of spring maize from 12.8 to 16.4 t/hm^2 were obtained at N rates of 250 kg/hm^2 and 400 kg/hm^2,but there was no significant difference between two treatments.Under no mulching,the grain yield at N rate of 400 kg/hm^2 was significantly lower than that of N rate of 250 kg/hm^2.2)N application,plastic film mulching significantly increased pre-silking and post-silking N and dry matter accumulation of spring maize,the effect of their interactions on the N and dry matter accumulation in post-silking was more effective than that of pre-silking.Under plastic film mulching,the proportion of N and dry matter accumulation in post-silking was 51.5%to 54.9%and 51.1%to 59.9%,respectively.High nitrogen and dry matter accumulation of pre-silking and post-silking were obtained with N rates of 250 kg/hm^2 and 400 kg/hm^2 under plastic film mulching,but N and dry matter accumulation at N rate of 400 kg/hm^2 did not significantly increase compared with N rate of 250 kg/hm^2.3)As the interaction between N application and plastic film mulching significantly increased pre-silking N accumulation and promoted post-silking growth,the interaction significantly promoted the translocation amount of N in vegetative organs of spring maize.Under plastic film mulching,N rates of 250 kg/hm^2 and 400 kg/hm^2 effectively promoted translocation of more N stored in the vegetative organs into grains.Under the same mulching condition,there was no significant difference between the N rates of 400 kg/hm^2 and 250 kg/hm^2 in N translocation from the vegetative organs.4)Plastic film mulching significantly increased nitrogen agronomic efficiency and N partial factor productivity under the same N application rate.N application,plastic film mulching and their interactions significantly increased N harvest index,which was 65.1%to 75.4%at N application rates of 250 kg/hm^2 and 400 kg/hm^2,there was no significant difference between two treatments.【Conclusions】The interaction between N application and plastic film mulching significantly promoted the N and dry matter accumulation of pre-and post-silking periods of spring maize,while this effect was more effective in the postsilking than in pre-silking,thus promoting N translocation from the vegetative organs into grain.The two factors synergistically increased the yield and the N harvest index of spring maize.
作者
王泽林
白炬
李阳
岳善超
李世清
WANG Ze-lin;BAI Ju;LI Yang;YUE Shan-chao;LI Shi-qing(College of Natural Resources and Environment,Northwest A&F University,Yangling,Shaanxi 712100,China;State Key Laboratory of Soil Erosion and Dryland Farming on Loess Plateau,Yangling,Shaanxi 712100,China)
出处
《植物营养与肥料学报》
CAS
CSCD
北大核心
2019年第1期74-84,共11页
Journal of Plant Nutrition and Fertilizers
基金
国家重点研发计划(2017YFD0201801
2017YFD0201807)资助
关键词
旱作春玉米
施氮量
覆膜
干物质
氮素吸收利用
dry-land spring maize
nitrogen application rate
plastic mulching
dry matter
nitrogen uptake and utilization
