论文部分内容阅读
以‘富士’苹果(Malus×Domestica Borkh.)幼树为试材,研究短截和拉枝处理后抽发的当年生新梢光合特性和叶绿素荧光的差异。结果表明:1)拉枝处理显著提高了叶片叶绿素含量和厚度,短截处理叶片叶面积显著高于拉枝处理和对照;2)短截处理显著提高了叶片净光合速率、蒸腾速率和气孔导度,但降低胞间CO2浓度。相反,拉枝处理提高了叶片的胞间CO2浓度,但降低了新梢叶片的净光和速率、蒸腾速率,气孔导度与对照基本相同;3)短截处理提高了叶片PSⅡ量子效率和光化学猝灭系数,降低了叶片非光化学猝灭系数,短截处理叶片PSⅡ量子效率和光化学猝灭系数在整个试验过程中显著高于其他处理,相反,叶片非光化学猝灭系数显著低于其他处理,对照组与拉90°处理叶片非光化学猝灭系数没有差异。这些结果表明,短截处理叶片PSⅡ量子效率的光合电子传递活性较大,较多的能量用于CO2同化,而用于热耗散的能量相对较少。相反,拉枝叶片PSⅡ量子效率的光合电子传递活性较低,用于热耗散的能量相对较多,而用于CO2同化能量较少。
The young ’Malus × Domestica Borkh’ saplings were used as materials to study the differences of photosynthetic characteristics and chlorophyll fluorescence between shoots and short shoots after shoot cutting. The results showed that: 1) Pinching treatment significantly increased leaf chlorophyll content and thickness, leaf area of stubble leaf was significantly higher than that of shoots and control; 2) Stubble treatment significantly increased leaf net photosynthetic rate, transpiration rate and stomatal conductance Degrees, but lower the intercellular CO2 concentration. On the contrary, the branching treatment increased the intercellular CO2 concentration of leaves, but decreased the net photosynthesis rate and the transpiration rate and stomatal conductance of the shoots. The short cut treatment increased the PSⅡ quantum efficiency and photochemistry The quenching coefficient decreased the non-photochemical quenching coefficient of leaves, the quantum efficiency of PSⅡ and the photochemical quenching coefficient of short leaf were significantly higher than those of other treatments during the whole experiment. On the contrary, the non-photochemical quenching coefficients of leaves were significantly lower than those of other treatments, There was no difference in the non-photochemical quenching coefficient between the control group and the pull-90 ° treatment. These results indicate that photosynthetic electron transfer activity of PSⅡ quantum efficiency of short-cut leaves is larger, more energy is used for CO2 assimilation, and energy for heat dissipation is relatively less. In contrast, photosynthetic electron-transporting activity of PSII at the pull-out branches was lower, energy used for heat dissipation was relatively higher, and energy used for CO2 assimilation was lower.