地膜覆盖栽培玉米根系形态对施氮量的响应  

Response of Maize Root Morphology to Nitrogen Application Under Film Mulch

作　　者：宋启龙 岳善超[2] 蔡立群[1,2] SONG Qilong;YUE Shanchao;Cai Liqun(College of Resources and Environmental Sciences,Gansu Agricultural University,Lanzhou 730070,China;State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau,Northwest A&F University,Yangling,Shaanxi 712100,China)

机构地区：[1]甘肃农业大学资源与环境学院,兰州730070 [2]西北农林科技大学黄土高原土壤侵蚀与旱地农业国家重点实验室,陕西杨凌712100

出　　处：《水土保持研究》2020年第2期23-29,共7页Research of Soil and Water Conservation

基　　金：国家重点研发计划(2017YFD0201801,2017YFD0201807).

摘　　要：为研究覆膜条件下氮肥用量对根系生长的影响,于2017年和2018年分别设置包括不施氮(N0)、适量施氮(N250)和过量施氮(N380)3个处理的田间试验,以先玉335为供试玉米品种,分别在拔节期和开花期采用3D Monolith(三维空间立体分析)取样法获得根系后,用WinRHIZO Pro软件分析根系的各项指标数据,评价不同氮肥用量根系生长情况。结果表明:覆膜条件下氮肥用量对根系的影响主要在上层土壤,适量施氮上层土壤中有更加发达的根系,表现为拥有更多的细根,适量施氮会显著增加玉米总根干重、根长、根表面积和根体积,增加幅度达86.1%,35.22%,62.2%,113.1%,而过量氮肥投入虽然在开花期对深层土壤中根系略有促进,但总量上仍然表现出抑制作用,过量施氮对玉米总根干重、根长、根表面积和根体积的降低幅度分别达18.4%,20.6%,18.6%和19.6%,均达显著水平。综合各指标表明,250 kg/hm2是覆膜条件下适宜根系生长的氮肥施用量,过高氮肥投入在造成资源浪费的同时会显著抑制根系生长。In order to study the effect of nitrogen application rate on root growth under film mulch conditions,field trials including no application of nitrogen,appropriate nitrogen application and excessive nitrogen application were carried out.The tested maize variety was Xianyu 335.The root system was obtained by 3 D Monolith sampling method.The root index data were obtained by WinRHIZO Pro software analysis.The root growths under different nitrogen fertilizer rates were evaluated.The results showed that the main effect of nitrogen application rate on the root system under the mulch condition was found in the upper layer soil;there was a more developed root system in the upper layer with application of nitrogen,there were more fine roots,and the appropriate amount of nitrogen fertilizer significantly increased the dry weight of the total root,root length,root surface area and root volume of the corn,the increment rates were 86.1%,35.22%,62.2%and 113.1%,respectively,while the excess nitrogen fertilizer increased in the root slightly during the flowering stage,but still showed the inhibition on roots,the reduction rates of root dry weight,root length,root surface area and root volume of corn were 18.4%,20.6%,18.6%and 19.6%,respectively.The study suggests that the nitrogen fertilizer application rate 250 kg/hm^2 is suitable for root growth under film mulching condition.Excessive high nitrogen fertilizer input can significantly inhibit root growth and waste resources.

关 键 词：覆膜 氮肥施用 玉米根系 

分 类 号：S513[农业科学—作物学]