夏玉米个体生长发育中叶片光合速率的动态特征  

Studies on the Dynamic Changes of the Photosynthetic Rates of the Leaves Duration the Course of the Growth and Development of Summer-Sown Corn (Zea Mays L.)

作　　者：赵明[1] 郑丕尧[1] 王瑞舫[1] 

机构地区：[1]北京农业大学作物栽培生态生理研究室

出　　处：《作物学报》1992年第5期337-343,共7页Acta Agronomica Sinica

摘　　要：在夏玉米生育过程中,系统地测定了个体和单叶水平的光合速率动态过程以及对影响叶片光合速率的主要因素的分析表明:在个体水平内,每一叶片的动态表现形式基本相同。初步可分为四个连续的阶段:①Ph(净光合速率)和LA(叶面积)同步增长;②Ph、LA高值出现;③Ph缓降;④叶片衰老Ph速降。不同叶位叶片在光合速率的动态过程中所达到的最大值没有明显的差别,但历经时间的区别较大,特别是第三阶段,靠近果穗叶位光合速率下降缓慢、维持时间长。不同品种在灌浆期,主要叶位光合速率的形式变动也在第三阶段。平展型品种京黄119出现下降后又有回升现象;紧凑型品种“掖单2号”则表现出缓慢渐降趋势。在单叶片内,随着叶片的生长,光合优势部位从叶顶部向基部迁移。相对光合速率表现为未展幼叶顶部高;展开的壮叶中部高;衰老叶片茎部高。在田间条件下,随着个体的生长发育,叶片对影响光合作用的主因素光的利用和所处的光照条件具有一定的协调和相对合理性。The dynamic Changeas of the photosynthetic rates (Pn) of individual plants andindividual leaves were studied during the course of growth and development ofSummer-sown corn. The results indicated that the pattern of the course of the dynamicchamges of the Pn of every individual leaf was fundementally the same. The coursecould be divided into 4 phases with the following characteristics respectionly: (1) Pnand LA (leaf area) increase similarity; (2) Maximum values of Pn and LA appear;(3)Pn decrease slowly; (4) The Leaf is getting old, Pn decrase rapidity. Nodifference was observed between the maximum values of leaves at different position,butthere were significant difference between the duration of their respective diffrent phase,espective the 3rd phase. The Variation of the pattern of Pn of different corn hybridsalso happened at the 3rd phase. During the filling stage, the Pn of the lax typecorn hybrid uJinghuang 119' increase slightly again after first decrease. There was noSuch 2nd increase with the compact type 'yedan 2'. The maximum activities ofphottosynthesis moved gradually from the top part of the leaf to middle and basicalparts with the growing of the leaf. Light is the most important factor influencingphotosynthesis under field condition. During the course of growth and development ofthe corn plant, the leaf could adapt to a certain extent to the existing lightconditions.

关 键 词：玉米 叶片 光合速率 动态变化 

分 类 号：S513.01[农业科学—作物学]