根区施肥条件下氮肥品种及施氮量对玉米苗期根系特征及生长的影响  

Effects of nitrogen fertilizer varieties and nitrogen application rate on root characters and growth of maize seedlings under root-zone fertilization

作　　者：杨朔 胡仁 侯俊 李锦涛 黄飞 聂玺斌 胡洋 李炫 何文祥 孔小雁 YANG Shuo;HU Ren;HOU Jun;LI Jin-tao;HUANG Fei;NIE Xi-bin;HU Yang;LI Xuan;HE Wen-xiang;KONG Xiao-yan(College of Agriculture,Yangtze University,Engineering Research Center of Ecology and Agricultural Use of Wet land Ministry of Education,Jingzhou Hubei 434025;Jingmen Farmx Agricultural Technology Co.,LTD,Jingmen Hubei 448200)

机构地区：[1]长江大学农学院/湿地生态与农业利用教育部工程研究中心,湖北荆州434025 [2]荆门法麦克斯农业科技有限公司,湖北荆门448200

出　　处：《中国土壤与肥料》2023年第9期111-119,共9页Soil and Fertilizer Sciences in China

基　　金：长江大学湿地生态与农业利用教育部工程研究中心开放基金(KF202109);国家重点研发计划(2017YFD0200705)。

摘　　要：根区施肥条件下根系周围养分浓度升高,根系对养分的吸收利用进一步提高,而苗期玉米根系较脆弱,因此,探索苗期玉米根系对根区施氮的响应有利于玉米高产高效,研究根区施氮下玉米苗期根系特征及分布可深化根区施肥理论,同时为玉米精准施肥提供理论依据。采用盆栽试验,以不施氮为对照(CK),设置2个氮肥品种[尿素(UR)和控释尿素(CRUR)],模拟4个施氮水平(N 90、135、180和225 kg/hm2),以不施氮肥为对照(CK),研究根区施肥条件下氮肥品种及施氮量对玉米苗期根系形态及分布的影响。结果表明:移栽后10 d,各处理间无显著差异。移栽25 d后,根区施尿素处理的根系指标随着施氮量的增加先升高后降低;而根区施控释尿素处理相应的根系指标随着施氮量的增加而增加或保持稳定。UR135和CRUR225处理根系特征较高,与CK相比提高了根系生物量(25.41%和64.37%)、总根长(40.14%和53.45%)、总根表面积(30.50%和32.52%)、总根体积(55.94%和46.72%)、平均直径(20.01%和23.18%)和根系活力(49.44%和50.64%)等,而UR225则均降低。不同土层根系生物量也受到根区附近氮肥品种及施氮量的影响,0~5和5~10 cm土层根系生物量均表现为CRUR225≥CRUR180=UR135≥CRUR135>UR90=UR180=CRUR90>CK>UR225,与CK相比,CRUR225处理下的0~5和5~10 cm土层分别显著提高61.44%和69.79%,而UR225处理分别显著降低45.66%和36.01%。根区施尿素处理的地上部指标(叶长、叶宽、茎粗、株高、SPAD和地上部干重)随着施氮量的增加先升高后降低,而根区施控释尿素处理相应的地上部指标随着施氮量的增加而增加或保持稳定。与CK相比,UR135和CRUR225处理的叶长、叶宽、茎粗和株高分别显著提高44.86%和40.85%、47.59%和59.42%、34.38%和63.13%、43.55%和55.32%,而UR225处理的茎粗和株高分别降低4.69%和3.17%。综上所述,根区施肥条件下施用低和中施氮量(N 90和135 kg/hm2)的尿素可以促进玉米�The nutrient concentration around root-zone is high under the condition of root-zone fertilization(RZF),and the absorption and utilization of nutrients by roots would be further improved,but the maize root is relatively fragile at seedling stage,so exploring the response of maize root system at seedling stage to root-zone fertilization(RZF)of nitrogen(N)is conducive to achieve high yield and use efficiency.A pot experiment was conducted to study the characteristics and distribution of maize root system at seedling stage under RZF of N,and to develop the theory of RZF and provide theoretical basis for precision fertilization of maize.Two N fertilizer varieties(urea and controlled-release urea,marked as U and CRU,respectively)and four N application rates(N 90,135,180,225 kg/hm2)were conducted to study the effects of N fertilizer varieties and N application on the root morphology and distribution of maize seedlings under RZF.The results showed that there were no significant differences among all treatments after 10 d after transplanting.After 25 d of transplanting,the root indices(root biomass,total root length,total surface area,total volume,average diameter,root activity)of U treatments under RZF were increased first and then decreased with the increase of N rate.However,the root indices of RZF with CRU increased or kept stable with the increased N rate.Compared with CK,the root biomass(25.41%and 64.37%),total root length(40.14%and 53.45%),total root surface area(30.50%and 32.52%),total root volume(55.94%and 46.72%),average diameter(20.01%and 23.18%)and root activity(49.44%and 50.64%)of UR135 and CRUR225 were significantly increased,while those of UR225 were significantly decreased.The root biomass of different soil layers was also affected by N fertilizer variety and N application.The root biomass of 0-5 and 5-10 cm soil layers ranked as:CRUR225≥CRUR180=UR135≥CRUR135>UR90=UR180=CRUR90>CK>UR225,the 0-5 and 5-10 cm soil layers of CRUR225 were significantly increased by 61.44%and 69.79%,respectively,compared wit

关 键 词：根区施肥 玉米 根系 氮肥品种 苗期 

分 类 号：S513[农业科学—作物学]