土壤水分对冬小麦生长后期光能利用及水分利用效率的影响  

Effects of Soil Moisture on Radiation Utilization during Late Growth Stages and Water Use Efficiency of Winter Wheat

作　　者：房全孝[1] 陈雨海[2] 李全起[2] 于舜章[2] 罗毅[1] 于强[1] 欧阳竹[1] 

机构地区：[1]中国科学院地理科学与资源研究所,北京100101 [2]山东农业大学,山东泰安271018

出　　处：《作物学报》2006年第6期861-866,共6页Acta Agronomica Sinica

基　　金：中国科学院禹城实验站开放课题基金项目(YC2002006);"聊城市国家计委大型优质小麦生产基地项目"(20021106)

摘　　要：通过控制不同土壤水分条件形成不同的小麦（Triticum aestivum L.）群体结构,测定了抽穗到成熟期间小麦冠层光合有效辐射（PAR）截获及垂直分布、干物质积累和产量.研究表明,不同处理小麦冠层对PAR的截获量差异较小（小于15.7%）,但冠层上部（60～80 cm）的PAR截获量和生长后期PAR转化效率差异明显（100.7%和63.7%）,与产量和光能利用效率变化一致,可见土壤水分是通过改变小麦群体内PAR垂直分布及PAR转化效率对作物产量和光能利用效率产生影响.抽穗到成熟期间维持小麦冠层上部PAR截获率在50%左右是实现高产的重要保证.随着土壤水分改善,冬小麦光能利用率和产量持续增加,但水分利用效率却先于二者提前降低,说明改善水分利用效率是提高华北地区农业气候资源利用效率的关键.在底墒充足的条件下,分别在拔节和挑旗期灌水60ma可获得较高的光能和水分利用效率及经济产量.Water stress is a frequent and critical limit to wheat （ Triticum aestivum L. ） production in the North China Plain. It has been shown that photosynthetic active radiation （PAR） has close relation to crop production, and water stress affects the biosynthetic procedure remarkably. However, its mechanism is still not clear. An experiment was conducted at Yucheng ecological station in Shandong Province to investigate the interception and conversion efficiencies of PAR in the canopy from heading to maturity stages, and water use efficiency （WUE） of winter wheat at different soil moisture levels. The relationship between soil moisture level and PAR vertical distribution in wheat canopy, and its influences on grain yield, PAR use efficiency and WUE were evaluated. Different supplemental irrigation amounts from 0 to 180 mm and timings from jointing to grain filling stages were designed to attain various soil moisture levels, which resulted in different wheat populations and canopy structures. These soil moisture levels showed substantial influences on PAR interception and distributions in canopy from heading to maturity stages, and subsequent PAR and water use efficiencies. No great difference （less than 15.7% ） in PAR intercepted by the wheat canopies was found between these soil moisture treatments during this period. While great differences in PAR intercepted by the top layer of the canopy （60-80 cm） （100.7%） and in PAR conversion efficiency （63.7 % ） were found between these treatments （Table 4 and Fig. 4）. This result was mainly caused by the changes in the vertical distributions of leaf area index （ Fig. 3） and in leaf photosynthesis capability caused by the different soil moisture levels. Maintaining about 50% PAR rate intercepted by the top canopy layer （60-80 cm） from heading to grain filling stages is very important for obtaining high grain yield and PAR use efficiency for winter wheat. With soil moisture improving, the PAR use efficiency during the late growth stages an

关 键 词：土壤水分 冬小麦 冠层结构 光能和水分利用效率 

分 类 号：S512.1[农业科学—作物学]