综合农艺管理对夏玉米叶片衰老特性的影响  

Effects of Integrated Agronomic Practices on Leaf Senescence Physiological Characteristics of Summer Maize

作　　者：朱昆仑[1] 靳立斌[1] 董树亭[1] 赵斌[1] 刘鹏[1] 张吉旺[1] 

机构地区：[1]山东农业大学农学院/作物生物学国家重点实验室,山东泰安271018

出　　处：《中国农业科学》2014年第15期2949-2959,共11页Scientia Agricultura Sinica

基　　金：山东省现代农业产业技术体系建设经费(SDAIT-01-022-05);山东省玉米良种工程项目;公益性行业(农业)科研专项(201103003)

摘　　要：【目的】研究综合农艺管理对夏玉米叶片衰老特性的影响。【方法】以郑单958为试验材料,对播期、播种方式、密度、氮肥施用时期及用量和收获时间等农艺措施进行优化组合,设置综合农艺管理试验,共4个处理:按当地农户习惯即麦田后期套种玉米、苗期一次性施氮和苞叶变白、籽粒变硬时收获等设置为处理1(T1);在此基础上改套种为直播,减少氮肥施用量,优化施肥时期,延迟收获时间,设置为处理2(T2);在T2的基础上进一步提高施肥量,增加磷、钾肥比例,将氮肥分次施用,增加种植密度,以期达到最高产量,设置为处理3(T3);在T3的基础上减少施肥量,进一步优化施肥时期,适当降低种植密度,设置为处理4(T4)。然后以T4处理为基础设置单因素施氮量试验(0、129.0、184.5和300.0 kg N·hm-2,分别记作N0、N1、N2和N3),研究综合农艺管理和施氮量对夏玉米叶面积指数、叶片光合色素含量、超氧化物歧化酶(SOD)活性、过氧化氢酶(CAT)活性、过氧化物酶(POD)活性和丙二醛(MDA)含量的影响。【结果】从大喇叭口期(V12)到抽雄后42 d,T4处理的LAI平均维持在4.4以上,显著高于T1和T2处理,且后期下降缓慢。在施氮量试验中,LAI随施氮量的增加而增加,从抽雄后28 d到成熟期(R6),N3的LAI平均下降了14.9%,高于其他施氮处理的降幅。综合农艺管理试验(MT)和施氮量试验(NT)的叶片光合色素含量均呈单峰曲线变化,在抽雄后14 d达到最大值,之后逐渐下降,从抽雄后14—42 d,T1、T2、T3和T4处理叶绿素(a+b)的含量分别减少了21.1%、22.0%、27.2%和18.4%,类胡萝卜素含量分别减少了26.6%、26.9%、32.2%和25.0%。抽雄后42 d,T4的叶绿素a、叶绿素b、叶绿素(a+b)和类胡萝卜素含量分别较T1提高了6.0%、13.0%、6.9%和9.3%。NT试验中叶绿素a、叶绿素b和叶绿素(a+b)的含量随施氮量的增加而增加;N3处理的类胡萝卜素含量生育后期急剧下降,到抽�[Objective]This study is to explore the effects of integrated agronomic practices on leaf senescence physiological characters of summer maize. [Method] Zhengdan958 was used as experimental material, integrated agronomic managements experiment （MT）, including 4 treatments of T1, T2, T3 and T4, and nitrogen rate experiment （0, 129.0, 184.5, 300.0 kg N hm-2, signed by N0, N1, N2, N3） which was based on T4 treatment were designed to explore the effects of integrated agronomic practices and nitrogen rate on leaf area index （LAI）, photosynthetic pigments content, superoxide dismutase （SOD）, catalase （CAT） and peroxidase （POD） activities and malondialdehyde （MDA） content in ear leaves of summer maize through the optimal combinations of planting methods, sowing and harvest date, as well as nitrogen fertilizer application timing and rate. [Result] LAI of T4 was always above 4.4 from V12 to 42 days after tasseling （VT）, which was significantly higher than those of T1 and T2, and the LAI reduction of T4 was slower in later growing period. As for nitrogen rate treatments （NT）, the LAI was increased with the increasing of nitrogen rate. The LAI of N3 decreased by 14.9% from 28 days after VT to R6 which was higher than those of the other treatments. As for MT and NT, the photosynthetic pigments content got the maximum value on 14 day after VT and then decreased, following the change of unimodal curve. From 14 days after VT to 42 days after VT, the chlorophyll （a＋b） content of T1, T2, T3, T4 decreased by 21.1%, 22.0%, 27.2% and 18.4% and the carotenoid content of T1, T2, T3, T4 decreased by 26.6%, 26.9%, 32.2% and 25.0%, respectively. On 42 day after VT, the content of chlorophyll a, chlorophyll b, chlorophyll （a＋b） and carotenoid in T4 were increased by 6.0%, 13.0%, 6.9%, 9.3% compared to T1, respectively. As for NT, the content of chlorophyll a, chlorophyll b and chlorophyll （a＋b） increased significantly with the increasing of nitrogen rate. The carotenoid content of N3 de

关 键 词：夏玉米 综合农艺管理 施氮量 保护酶活性 

分 类 号：S513[农业科学—作物学]