银杏新梢叶片光合与荧光特性研究

Study on Photosynthesis and Fluorescence Characteristics of Ginkgo biloba L. Shoots Leaves

以南京师范大学植物园生长的7a生银杏苗木为试材,选择银杏植株当年生新梢叶片和同株多年生枝条叶片为研究对象,分别测定了新梢叶片与老枝叶片叶绿素含量、光合及荧光参数,研究了银杏新梢叶片的光合特性。结果表明:与老枝叶片相比,银杏新梢叶片叶绿素a、b含量相对低,但是Chl a/b的比值较高;新梢叶片的净光合速率(Pn)比老枝高,光合日变化显示新梢和老枝叶片具有光合"午休"现象,主要原因是气孔因素导致;叶绿素荧光方面表现为,新梢叶片具有更高的最大光化学效率(Fv/Fm)和PSⅡ潜在活性(Fv/F0)。

Taking 7-years-old pot-cultured Ginkgo biloba L.seedling as test material,the photosynthesis and fluorescence characteristics of Ginkgo biloba L.shoots leaves were studied,the chlorophyll contents,photosynthesis and fluorescence parameters were measured.The results showed that,compared with perennial branches leaves,the chlorophyll contents in shoots leaves was lower but chlorophyll a/b in contrast.At the same time,the shoots leaves also had a higher photosynthesis rate（Pn）.The diurnal variation of photosynthesis in shoots leaves had a ＇midday depression＇ phenomenon,it mainly due to stomatal factors;on the other hand,fluorescence parameters showed that shoots leaves with high quantum yield of primary photochemistry（Fv/Fm）and conformation term for primary photochemistry（Fv/F0）.