灌溉模式对不同群体小麦光合特性的调控机制  

Regulation mechanism of irrigation schedule on population photosynthesis of winter wheat

作　　者：刘丽平[1,2] 欧阳竹[1] 武兰芳[1] 孙振中[1,2] 李发东[1] 

机构地区：[1]中国科学院地理科学与资源研究所中国科学院生态系统网络观测与模拟重点实验室,北京100101 [2]中国科学院研究生院,北京100049

出　　处：《中国生态农业学报》2012年第2期189-196,共8页Chinese Journal of Eco-Agriculture

基　　金：中国科学院知识创新工程重大项目(KSCX1-YW-09-06);国家重点基础研究发展计划(973计划)项目(2005CB121106)资助

摘　　要：为明确灌溉模式对不同群体小麦光合特性的调控机制,在大田条件下设置了不灌水(W0)、灌1水(W1j,拔节期灌水;W1b,孕穗期灌水)、灌2水(W2,拔节期和孕穗期灌水)、灌3水(W3,拔节期、孕穗期和灌浆期灌水)5种灌溉模式和基本苗180株.m?2(D1)、300株.m?2(D2)和450株.m?2(D3)3种密度的二因素试验,研究了灌溉模式对不同群体小麦光合特性的影响。结果表明:灌溉明显改善了群体光合速率。在一定灌溉总量范围内,灌溉次数与群体光合速率呈抛物线型关系。较多的灌溉次数下群体光合速率的提高归因于LAI增大和群体光截获的增加。群体光合速率与冠层透光率呈极显著的负相关,灌浆期群体光合速率与花后干物质积累量和产量呈极显著的正相关。主效应及偏相关分析表明:W0、W1j、W1b、W3群体光合速率主要受群体透光率和叶面积的影响,W2群体光合速率的提高主要受旗叶净光合速率的影响。综合产量和群体光合速率等因素,春季灌2水(拔节水和孕穗水)的小麦群体上层截获光较多,中下层通风透光良好,群体光合同化能力最强,花后干物质积累量和产量最高;在此基础上采取密度为300株.m?2基本苗能够提高生育后期的群体光合速率,延长其高值持续时间,增加小麦籽粒产量。The main mode of resource assimilation relevant to wheat grain yield is photosynthesis.Irrigation is a critical cultivation measure for plant growth and photosynthesis.Despite the tremendous progress in understanding the effects of irrigation on photosynthesis,the mechanism of irrigation on population photosynthesis（PP） remains unclear.A field experi-ment was therefore conducted to clarify the regulation mechanisms of different irrigation schedules on population photosynthetic of winter wheat.The experiment included 5 irrigation schedules [no irrigation（W0）,1-time irrigation at jointing（W1j） or booting（W1b） stage,2-time irrigation at jointing and booting stages（W2）,and 3-time irrigation at jointing,booting and grain-filling stages（W3）] and 3 planting densities [180（D1）,300（D2） and 450（D3） seedlings per square meter].The results indicated that irrigation signifi-cantly improved PP.The relationship between PP and irrigation time/volume was to some extent parabolic.Improvements in PP（re-sulting from more irrigation time/volume） were mainly related to increases in leaf area index（LAI） and population light interception.PP exhibited a significantly negative correlation with percent canopy light transmittance.PP at grain filling stage was significantly positively correlated with accumulated dry matter and grain yield.In terms of main effects,partial correlation analysis showed that PP of W0,W1j,W1b and W3 was regulated by percent population light transmission and leaf area.On the other hand,W2 PP was mainly influenced by flag-leaf photosynthetic rate.This indicated that spring irrigations at jointing and booting stages（W2） led to higher photosynthetic rate and yield output.On this basis,planting 300 seedlings per square meter was the optimum combination.The combination of W2 and D2 increased PP during mid-late growth stages and extended high PP duration,which ultimately in-creased grain yield.

关 键 词：小麦 灌溉模式 基本苗密度 群体光合特性 干物质积累 产量 

分 类 号：S521.11[农业科学—作物学]