玉米自交系叶片水分利用效率差异性及其生理变化

Water Use Efficiency of Maize Inbred Line Leaf and the Physiological Changes

为选育抗旱性强、耗水少、水分利用效率高的品种。以22个玉米自交系为材料,采取正常灌溉和适度水分胁迫处理,对自交系叶片水分利用效率(WUE)、光合速率(Pn)、蒸腾速率(Tr)、气孔导度(Gs)、胞间CO2浓度(Ci)、相对叶绿素值(SPAD)和荧光动力学参数进行研究。结果表明,不同自交系WUE差异显著,而且对水分的敏感程度也存在显著差异;适度水分胁迫使Gs、Pn、Tr都有所下降,但各材料的下降幅度不同,其中Tr的下降幅度要大于Pn下降的幅度,使得WUE比正常灌水处理下有所升高;自交系WUE与Pn、最大荧光(Fm)、可变荧光(Fv)、PSⅡ原初光能转换效率(Fv/Fm)及PSⅡ潜在活性(Fv/Fo)达到显著相关。

For the breeding of drought resistant,low water consumption,high water use efficiency of varieties,the water use efficiency（WUE） of leaf can affect the yield of crop directly.In order to determine the relationship between WUE and genetics background,and to elucidate the mechanism of that how WUE affect the yield,22 maize inbred lines were grown under water controlled condition.the following physiology index,water use efficiency of inbred lines leaf（WUE）,photosynthetic rate（Pn）,transpiration rate（Tr）,stomatal conductance（Gs）,intercellular CO2 concentration（Ci）,the relative values of chlorophyll（SPAD） and fluorescence parameters of inbred lines leaf,were assayed.The results showed that there was significant difference in the WUE among different inbred lines.And significant difference in the degree of sensitivity to water among these inbred lines was also observed;Gs,Pn,Tr declined in moderate water stress,among the decrease of Tr was greater than the decrease of Pn,so that the WUE was increased than in the normal irrigation treatments;the relation of WUE of different inbred lines leaf and Pn,Fm,Fv,Fv/Fm and Fv/Fo was significant correlation.