Characteristics of Photosynthesis and Spectra Properties of Thylakoid Membranes in the Yellow-Green Leaf Mutant of Chrysanthemum | 菊花黄绿叶突变体的光合与类囊体膜光谱

Chinese. 以菊花‘金陵国紫’黄绿叶突变体为试验材料,研究该突变体黄绿叶的绿叶与黄叶组织光合与类囊体膜光谱特性。对突变体黄绿叶中绿叶与黄叶组织的光合速率、光响应曲线、气孔特征与类囊体膜光谱特性进行测定与分析。结果表明：与绿叶组织相比,突变体黄叶组织的净光合速率、光饱和点、暗呼吸速率、表观量子效率均显著低于绿叶组织,而光补偿点则显著高于绿叶组织;黄叶组织的气孔限制值低于绿叶组织,非气孔限制值则显著高于绿叶组织,而黄叶与绿叶组织的气孔特征并无显著性差异。突变体黄叶组织类囊体膜叶绿素捕光能力与受激发能力均显著低于绿叶组织。黄叶组织光合能力显著低于绿叶,其较低光合能力形成的原因是由非气孔因素造成的,而类囊体膜功能的下降是导致其光合功能下降的一个重要非气孔因素。

English. In order to study photosynthetic mechanism of the yellow-green leaf mutant――‘Jinglingguozi’ of chrysanthemum, the characteristics of photosynthesis and the spectra properties of thylakoid membrane in the green and yellow leaf tissue of the mutant were studied. We measured the photosynthesis, stomatal characteristics, room temperature absorption spectra, chlorophyll emission fluorescence spectra of thylakoid membrane. The results that compared to the green leaf tissue of the mutant, the yellow leaf tissue had lower net photosynthetic rate （Pn）, light saturation point （LSP）, dark respiration rate （Rd）, apparent quantum yield （AQY）, but higher light compensation point （LCP）. The yellow leaf tissue had lower stomata limit value （Ls）, but higher non-stomata limit value. There was no significant difference in the characteristics of stomatal microstructure between the green leaf and yellow leaf tissue. The absorption spectra and fluorescence spectra significantly decreased in the yellow leaf tissue. The yellow leaf tissue had significantly lower capacity of the capture and excitation of light energy and lower the photosynthetic capacity than the green leaf tissue did, which was caused by non-stomata factors, such as a decrease of the function of thylakoid membrane.