增施氮肥对夏玉米花后高温胁迫下籽粒碳氮代谢的影响  

Effects of application nitrogen on carbon and nitrogen metabolism of summer maize grain under post-silking heat stress

作　　者：王瑞 李向岭 郭栋 王新兵[2] 马玮[2] 李从锋[2] 赵明[2] 周宝元[2] WANG Rui;LI Xiang-Ling;GUO Dong;WANG Xin-Bing;MA Wei;LI Cong-Feng;ZHAO Ming;ZHOU Bao-Yuan(College of Agronomy and Biotechnology,Hebei Normal University of Science&Technology/Hebei Key Laboratory of Crop Stress Biology,Qinhuangdao 066004,Hebei,China;Institute of Crop Sciences,Chinese Academy of Agricultural Sciences/Key Laboratory of Crop Physiology and Ecology,Ministry of Agriculture and Rural Affairs,Beijing 100081,China;Haikou Cigar Research Institute,Hainan Provincial Branch of China National Tobacco Corporation,Haikou 571100,Hainan,China)

机构地区：[1]河北科技师范学院农学与生物科技学院/河北省作物逆境生物学重点实验室,河北秦皇岛066004 [2]中国农业科学院作物科学研究所/农业农村部作物生理生态重点开放实验室,北京100081 [3]中国烟草总公司海南省公司海口雪茄研究所,海南海口571100

出　　处：《作物学报》2023年第12期3342-3351,共10页Acta Agronomica Sinica

基　　金：国家重点研发计划项目(2022YFD2300803);中央级公益性科研院所基本科研业务费专项(S2022ZD05);财政部和农业农村部国家现代农业产业技术体系建设专项(CARS-02-12)资助。

摘　　要：花后高温是影响黄淮海夏玉米籽粒灌浆及产量形成的主要逆境胁迫之一。目前关于增施氮肥缓解灌浆期高温胁迫对小麦、玉米和水稻等作物产量形成的抑制作用已得到证实,但相关调控途径及其生理机制尚不明确。本研究选用郑单958(Zhengdan 958,ZD958)和先玉335(Xianyu 335,XY335)2个玉米品种为试验材料开展盆栽试验,设置2个温度处理,分别为自然环境温度(ambient temperature,CK)和温室增温处理(heat stress,HS);3个施氮水平,分别为低施氮量(low nitrogen application rate,LN):120 kg hm–2,中施氮量(middle nitrogen application rate,MN):240 kg hm–2和高施氮量(high nitrogen application rate,HN):360 kg hm–2,研究增施氮肥对花后初期高温胁迫下玉米碳氮代谢的影响。结果表明,与自然温度比,花后增温(35℃)处理20 d导致ZD958和XY335两个品种的成熟期粒重降低10.6%~19.3%,但粒重降幅随着施氮量增加而下降,中施氮量(MN)和高施氮量(HN)下粒重降幅(10.6%~11.2%)小于低施氮量(LN)下粒重降幅(16.2%~19.3%),说明增施氮肥可以显著提高花后高温胁迫下的玉米粒重。这主要是因为增施氮肥有效缓解了花后初期高温胁迫对玉米籽粒氮代谢的抑制作用,显著提高了谷氨酰胺合成酶(GS)和谷氨酸合成酶(GOGAT)等氮代谢关键酶活性,同时维持了碳代谢关键酶蔗糖磷酸合成酶(SPS)和蔗糖合成酶(SS)活性,促进了籽粒可溶性糖合成增加,从而保证了较高的籽粒灌浆物质基础。综上所述,增施氮肥可以缓解玉米花后初期高温胁迫对籽粒碳、氮代谢的抑制,促进籽粒中同化物积累而增加粒重,为黄淮海区夏玉米抗逆稳产栽培提供了思路。Post-silking heat stress is one of the main stresses affecting grain filling and yield formation of summer maize in the Huang-Huai-Hai plains.At present,it has been confirmed that increasing nitrogen application can alleviate the inhibition of post-silking heat stress on the yield formation of wheat,maize,and rice,but the regulatory pathways and physiological mechanisms remain unclear.In this study,two maize varieties Zhengdan 958(ZD958)and Xianyu 335(XY335)were selected in pot experiment.To study the effects of increased nitrogen application on carbon and nitrogen metabolism of maize under heat stress during post-silking stage,two temperature treatments[ambient temperature(CK)and heat stress(HS)],three nitrogen application levels[low nitrogen application rate(LN):120 kg hm–2,middle nitrogen application rate(MN):240 kg hm–2,and high nitrogen application rate(HN):360 kg hm–2]were set.The results showed that the dry weight of ZD958 and XY335 cultivars at maturity stage decreased by 10.6%–19.3%after 20 days of post-silking heat stress(35oC)compared with the ambient temperature.However,the decrease of kernel dry weight under heat stress was gradually decreased with the increase of nitrogen application rate,and the decrease rate(10.6%–11.2%)of kernel dry weight under medium nitrogen application rate(MN)and high nitrogen application rate(HN)was lower than that(16.2%–19.3%)under low nitrogen application rate(LN),which indicating that increased nitrogen application could significantly increase maize kernel dry weight under post-silking heat stress.This was mainly due to the increasing application of nitrogen effectively alleviated the inhibitory effect of early post-silking heat stress on maize grain nitrogen metabolism,and significantly increased the activities of key enzymes of nitrogen metabolism such as glutamine synthetase(GS)and glutamate synthetase(GOGAT).At the same time,the activities of sucrose phosphate synthetase(SPS)and sucrose synthetase(SS),which were key enzymes of carbon metabolism,were maint

关 键 词：夏玉米 高温胁迫 增施氮肥 碳氮代谢 

分 类 号：S513[农业科学—作物学]