水分胁迫对赤霞珠葡萄光合特性的影响

The Effects of Water Stress on Photosynthetic Characteristics of Cabernet Sauvignon

为了探究水分胁迫对赤霞珠葡萄光合特性的影响,以限根条件下3a生赤霞珠为材料,根据叶片的基础水势Ψb,结合时控仪实现全自动控制灌水,以叶片的基础水势Ψb,在0 MPa≥Ψb≥-0.2 MPa范围时,葡萄处于无水分胁迫(CK)为对照,分别设置3个水分胁迫水平(轻度水分胁迫T1,Ψb在-0.2 MPa≥Ψb≥-0.4 MPa范围内;中度水分胁迫T2,Ψb在-0.4 MPa≥Ψb≥-0.6 MPa范围内;重度水分胁迫T3处理,-0.6 MPa≥Ψb时),研究了不同程度水分胁迫对赤霞珠葡萄光合特性的影响。结果表明:水分胁迫能不同程度的抑制赤霞珠光合色素(叶绿素a,叶绿素b,类胡萝卜素和总的叶绿素含量)的合成,并促进其分解,最终导致光合色素含量降低。同时,水分胁迫导致赤霞珠葡萄净光合速率(Pn)、蒸腾速率(Tr)及气孔导度(Gs)呈现下降的趋势,促使胞间CO2浓度(Ci)呈现先下降后上升的趋势,但水分胁迫在一定程度上增加了水分利用效率。

In order to explore the effects of water stresses on Photosynthetic Characteristics of Cabernet Sauvignon,the 3years of Cabernet Sauvignon cultivated under the condition of restricted roots is taken as study material.According to the pre-dawn leaf water potential（Ψb）,the control instrument is used to achieve automatic control of irrigation.The treatment withΨb of-0.2 MPa to 0MPa,no water stress,is taken as CK,and three treatments with different water stress level,including light degree withΨb of-0.4 MPa to-0.2 MPa,middle degree withΨb of-0.6 MPa to-0.4 MPa,and severe degree withΨb less than-0.6 MPa,are set to explore the effects of different Water stresses on Photosynthetic Characteristics of Cabernet Sauvignon.The results show that：different water stress levels can inhibit the synthesis of photosynthetic pigments of Cabernet Sauvignon,including chlorophylla,chlorophyllb,carotenoid and total chlorophyll,and promote their decomposition,which results in decreased Photosynthetic pigments finally.Moreover,water stress also leads to decreased net photosynthetic rate（Pn）,transpiration rate（Tr）and stomatal conductance（Gs）of Cabernet Sauvignon,promotes intercellular CO2（Ci）concentration to appear the trend of falling after rising,but increases water using efficiency to some extent.