摘要
开花后是作物产量形成的关键期,阐明该时期不同栽培模式下春玉米冠层不同部位叶片的衰老特性,有助于理解不同栽培模式产量差异的形成机制,为不同栽培模式玉米植株衰老调控提供理论依据。对密度、耕作方式和肥料运筹等农艺措施进行不同组合,模拟不同产量水平的栽培模式,设计了基础(ISP)、农户(FP)、高产高效(HH)和超高产(SH)4种栽培模式。通过叶面积(LA)动态变化模型y=ae^(b−cx)/(1+e^(b−cx))解析叶片衰老过程;通过测定不同部位叶片光合色素、抗氧化酶活性等指标,比较不同栽培模式玉米叶片的衰老特性。HH(12445.55 kg∙hm^(−2))和SH(13759.07 kg∙hm^(−2))的产量显著高于FP和ISP(P<0.05),分别较FP增产14.4%和26.4%;吐丝期和成熟期SH的干物重较HH分别提高18.5%和10.4%(P<0.05),HH较FP分别提高2.8%(P>0.05)和17.7%(P<0.05)。与FP相比,HH和SH叶片衰老启动晚且以上部叶片最为典型,平均衰老速率下降26.7%和18.0%,其叶片最大衰减速率出现的时间延长12 d和8 d,单株最大叶面积增加8.7%和6.6%。吐丝后0~60 d,HH和SH下部平均叶面积分别较FP高42.4%和17.3%。吐丝后,HH和SH的中下部叶片光合色素含量和保护酶活性均显著高于FP(P<0.05)。HH中下部叶片的保护酶活性始终维持在较高水平且生育后期下降缓慢。吐丝后,不同栽培模式玉米各部位叶片的MDA含量均呈上升趋势,且HH和SH的MDA含量与FP相比维持在较低水平。与农户模式相比,密植、深翻和分次施肥技术要素集成的高产高效和超高产栽培模式,花粒期冠层上部叶片衰老启动较晚,而中下部叶片面积较高且衰老较慢,吐丝后其色素含量较高且下降缓慢,同时叶片保护酶活性较高,显著减缓了中下部叶片衰老进程,有利于开花后光合物质同化,实现高产。
Post-silking is a critical period for maize yields.This study aimed to elucidate the senescence characteristics of spring maize leaves at different parts of the canopy under different cultivation modes,to understand the mechanism of yield formation and provide a theoretical basis for the regulation of senescence of maize plants in different cultivation models.Four cultivation modes with different agronomic measures were set up by integrating planting density,tillage method,and fertilizer management;they included inherent soil production(ISP),farmer household model(FP),high-yield and high-efficiency model(HH),and super-high-yield model(SH).The leaf area dynamic change model y=ae^(b−cx)/(1+e^(b−cx)) was used to analyze the senescence process of leaves,and photosynthetic pigment and antioxidant enzymes activities were measured in different parts of the leaves to compare the senescence characteristics of maize leaves under different cultivation modes.The yields of HH(12445.55 kg∙hm^(−2)) and SH(13759.07 kg∙hm^(−2)) were significantly higher than that of FP and ISP;they increased by 14.4%and 26.4%,respectively(P<0.05),compared with that of FP.The dry matter weight of SH increased by 18.5%and 10.4%compared with that of HH at silking and maturity stages(P<0.05),respectively,and that of HH increased by 2.8%(P>0.05)and 17.7%(P<0.05)compared with that of FP,respectively.Compared with FP,HH and SH started senescence later and the upper leaves were the most typical,with an average decrease in senescence rate of 26.7%and 18.0%,respectively(P<0.05).Compared with FP,the times to maximum reduction rate of relative green leaf area of HH and SH increased by 12 d and 8 d,and the maximum leaf area per plant increased by 8.7%and 6.6%,respectively(P<0.05).From 0 to 60 d after silking,the average leaf areas of lower canopy of HH and SH were 42.4%and 17.3%higher than that of FP,respectively(P<0.05).The photosynthetic pigment contents and protective enzymes activities of the lower and middle leaves of HH and SH plants were significantly higher than those of FP plants after silking.The activities of protective enzymes in the HH middle and lower leaves remained at a high level and decreased slowly during late growth period.After silking,the MDA content of all parts of the maize leaves in different cultivation modes tended to increase,and the MDA content of HH and SH remained at a lower level than that of FP.Compared with FP,for HH and SH with the integration of dense planting,deep tillage,and split fertilizer application technology,the leaf senescence started later in the upper part of the canopy during the flowering period,but the leaf area in the middle and lower parts showed higher and slower senescence.In addition,after silking,the pigment content was very high and decreased slowly,and the leaf protective enzyme activity was very high;this significantly slowed down the senescence process of middle and lower leaves and was conducive to photosynthesis assimilation and high yield.
作者
王丹
吕艳杰
姚凡云
徐文华
陈帅民
邵玺文
曹玉军
王永军
WANG Dan;LYU Yanjie;YAO Fanyun;XU Wenhua;CHEN Shuaimin;SHAO Xiwen;CAO Yujun;WANG Yongjun(College of Agronomy,Jilin Agricultural University,Changchun 130118,China;Institute of Agricultural Resources and Environment,Jilin Academy of Agriculture Sciences/Key Laboratory of Crop Eco-physiology and Farming System in the Northeastern,Ministry of Agriculture and Rural Affairs,Changchun 130033,China)
出处
《中国生态农业学报(中英文)》
CAS
CSCD
北大核心
2022年第12期1925-1937,共13页
Chinese Journal of Eco-Agriculture
基金
吉林省农业科技创新工程项目(CXGC2018ZY019)
现代农业产业技术体系项目(CARS-02-19)
国家重点研发计划项目(2016YFD0300103)
国家自然科学基金项目(31701349)资助。
关键词
春玉米
栽培模式
叶片衰老
保护酶活性
产量
Spring maize
Cultivation models
Leaf senescence
Protective enzyme activity
Yield