节水减氮对夏玉米干物质和氮素积累转运及产量的调控效应  

Regulation Effects of Water Saving and Nitrogen Reduction on Dry Matter and Nitrogen Accumulation,Transportation and Yield of Summer Maize

作　　者：王旭敏 雒文鹤 刘朋召 张琦 王瑞[1] 李军[1] WANG XuMin;LUO WenHe;LIU PengZhao;ZHANG Qi;WANG Rui;LI Jun(College of Agronomy,Northwest A&F University/Key Laboratory of Crop Physiecology and Tillage Science in Northwestern Loess Plateau,Ministry of Agriculture,Yangling 712100,Shaanxi)

机构地区：[1]西北农林科技大学农学院/农业部西北黄土高原作物生理生态与耕作重点实验室,陕西杨凌712100

出　　处：《中国农业科学》2021年第15期3183-3197,共15页Scientia Agricultura Sinica

基　　金：国家科技支撑计划(2015BAD22B02);国家自然科学基金(31801300)。

摘　　要：【目的】针对当前夏玉米生产中灌溉水资源不足和施氮过量的问题,本研究拟通过分析比较节水减氮模式与常规水氮模式对夏玉米生长和产量的调控效应,为开发夏玉米水肥减量增效的生产模式提供依据。【方法】于2018—2019年在陕西杨凌开展水氮二因素田间试验。灌溉设常规灌溉(800 m^(3)·hm^(-2))、减量灌溉(400 m^(3)·hm^(-2))和不灌溉(0)3个处理;施氮设常规施氮(300 kg N·hm^(-2))、减施25%(225 kg N·hm^(-2))、减施50%(150 kg N·hm^(-2))、减施75%(75 kg N·hm^(-2))和不施氮肥(0)5个处理,分析夏玉米产量、光合特性以及干物质(氮素)积累和转运特性。【结果】(1)减量灌溉、减氮25%的节水减氮模式较常规水氮模式对产量及产量构成因素无显著影响。(2)与常规水氮模式相比,减量灌溉、减氮25%对夏玉米叶面积指数(LAI)无显著影响,也能加快花前LAI上升速度且花后LAI下降缓慢;显著提高抽雄期穗位叶净光合速率10.0%,维持植株花后较高的穗位叶净光合速率,保证干物质生产。(3)减量灌溉和减氮25%较常规水氮模式对成熟期干物质积累量无显著影响,但干物质最大增长速率显著提高6.3%,最大增长速率出现日期显著提前0.8 d。(4)与常规水氮模式相比,减量灌溉、减氮25%处理花前干物质转运量、转运率和花前转运量对籽粒贡献率分别显著提高36.4%、40.1%和28.6%;花前氮素转运量、转运率以及转运量对籽粒的贡献率分别显著提高30.3%、22.0%和42.1%。花后干物质、氮素积累量以及对籽粒的贡献率在2种水肥模式下无差异。【结论】施氮225 kg·hm^(-2)、灌溉400 m^(3)·hm^(-2)的节水减氮模式能有效协调干物质和氮素的积累和转运,提高成熟期籽粒同化物分配比例,实现关中平原夏玉米节水减肥增效的生产目标。【Objective】In order to solve the problems of irrigation water resources scarcity and excessive nitrogen input in current summer maize cropping system,this study analyzed the regulating effects of maize growth and yield response between water-saving,nitrogen reduction mode and conventional water-nitrogen mode,so as to provide a theoretical basis for determining water-saving and nitrogen-reduction cultivation measures of summer maize.【Method】A different irrigation and nitrogen application field trial of summer maize was conducted in Yangling,Shaanxi province in 2018-2019.Three irrigation treatments were conventional irrigation(800 m^(3)·hm^(-2)),reduced irrigation(400 m^(3)·hm^(-2))and no irrigation(0);and five nitrogen treatments were as follows:conventional nitrogen application(300 kg N·hm^(-2)),reduced 25%(225 kg N·hm^(-2)),reduced 50%(150 kg N·hm^(-2)),reduced 75%(75 kg N·hm^(-2))and no N fertilizer(0),respectively.The study investigated the effects of water saving and nitrogen reduction on maize yield,photosynthetic characteristics,dry matter(nitrogen)accumulation and its transport characteristics.【Result】(1)Compared with conventional water-nitrogen mode(conventional irrigation and 300 kg N·hm^(-2)),the water-saving and nitrogen reduction mode(reduced irrigation and 225 kg N·hm^(-2))had no significant effect on maize yield and its components.(2)Compared with conventional water-nitrogen mode,the reduced irrigation and 225 kg N·hm^(-2) treatment had no impact on maize leaf area index(LAI),its LAI increased obviously before anthesis and decreased slowly after anthesis than that under other treatments.The net photosynthetic rate of ear leaf significantly increased by 10.0%at tasseling stage,and kept a higher net photosynthetic rate till the post anthesis period,this promoted the dry matter accumulation.(3)Reduced irrigation and 225 kg N·hm^(-2) had no remarkable influence on dry matter accumulation,but the maximum growth rate of dry matter accumulation was significantly increased by 6.3%,and

关 键 词：夏玉米 节水灌溉 减量施氮 干物质积累 转运 产量 

分 类 号：S513[农业科学—作物学]