遮荫对水稻冠层叶片SPAD值及光合、形态特性参数的影响  

Effect of shading on leaf SPAD values and the characteristics of photosynthesis and morphology of rice canopy

作　　者：杨虎[1] 戈长水[2] 应武[2] 杨京平[1] 李金文[1] 何俊俊[1] 

机构地区：[1]浙江大学环境与资源学院,浙江杭州310058 [2]杭州市农业科学研究院,浙江杭州310024

出　　处：《植物营养与肥料学报》2014年第3期580-587,共8页Journal of Plant Nutrition and Fertilizers

基　　金：浙江省自然科学基金资助项目(Y507005);国家自然科学基金(61174089)资助

摘　　要：SPAD(soil-plant analysis and development)计是一种快速、方便、非破坏性的诊断植物叶片相对叶绿素或氮含量的仪器,与传统的氮营养诊断方法相比,此仪器节省时间、劳力和资源。本试验通过未遮荫和遮荫的方法观察水稻冠层叶片SPAD值、叶绿素含量、叶绿素荧光、光合参数、叶片厚度和比叶重(叶片干重除以叶片的面积)等生理形态指标的变化,建立SPAD值与光系统II(PSII)最大量子产量(Fv/Fm)之间的回归关系。结果表明,遮荫条件下,甬优9号(YY9)和丙9363(B9363)冠层叶片变薄、SPAD值、叶绿素a/b、比叶重、电子传递速率(ETR)降低,但快速光曲线的初始斜率无明显变化;同时,遮荫导致了叶片的呼吸速率、最大净光合(Pmax)、量子效率、光补偿点和饱和点降低,表明水稻叶片为适应弱光环境,降低光合能力、减少呼吸消耗,以增加对有限光能的利用。不同光照条件下,水稻冠层叶片SPAD值与PSII的Fv/Fm的回归方程呈指数式关系(YY9 R2=0.896;B9363 R2=0.833),表明SPAD计可以快速、无损、有效地评估水稻冠层叶片的光合作用进程,当SPAD值小于35时,其光合过程可能处于受损状态。Soil-plant analysis and development （SPAD） meter is a quick, portable,non-destructive diagnostic tool for the measurement of relative chlorophyll or nitrogen （ N） content in leaves.SPAD meter is time, labor and resources saving compared to traditional N nutrition diagnosis methods .The experiment with and without shading treatments was conducted in paddy field with rice cultivars YY 9 and B9363.The physiomorphology indices including leaf SPAD values , chlorophyll contents , chlorophyll fluorescence and photosynthetic parameters , specific leaf weight and blade thickness in rice canopy were measured to establish the regression relationship between SPAD values and the maximum quantum output in photosystem II （ Fv/Fm of PSII） at rice growth stages .The results show that under the shading treatment , there is decline in the leaf SPAD values , chlorophyll a/b ratios, specific leaf weights and electron transport rate .The thickness of leaves becomes thin in rice canopy;the initial slopes of rapid light curves do not change obviously .The respiration rate, the maximum net photosynthetic efficiency （Pmax）, the quantum efficiency , light compensation point and saturation point of leaves are decreased to reduce photosynthetic capacity and consume through breath , and increase the utilization of limited light energy under weak light environment .Under both the shading and without shading treatments , exponential relationships exist between the leaf SPAD values and the Fv/Fm of PSII in rice canopy.For cultivar YY9, the coefficient of determination R2 is 0.896 and for B9363 is 0.833.Therefore, the leaf photosynthetic process in rice canopy can be evaluated quickly , non-destructively and efficiently using SPAD meter , and the SPAD reading of lower than 35 may be used to indicate the impairment in photosynthetic process of rice .

关 键 词：水稻 叶绿素荧光 SPAD值 遮荫 光合作用 

分 类 号：S511[农业科学—作物学]