芽变突变体彩叶杨光合特性及叶绿体超微结构的研究

Study on Photosynthetic Characteristics and Chloroplast Ultrastructure of Bud Mutant of Color-leaved Poplar

为探究彩叶杨芽变突变体中红杨和全红杨与野生型绿叶杨L2025生长差异的原因,本研究以芽变突变体彩叶杨中红杨和全红杨,以及野生型绿叶杨L2025为试验材料,对其叶绿体超微结构和光合特性进行研究。结果表明,中红杨和全红杨叶绿体基粒片层少,叶绿素合成受阻,其受阻位点可能位于CoprogenⅢ和ProtoⅨ之间,光合色素含量降低,光合作用减弱,净光速率仅为正常绿叶杨L2025的62%～73%。本研究从理论上证实了生产上全红杨、中红杨扦插生长慢的现象,为彩叶杨的推广繁殖提供了一定的参考依据。

In order to investigate the mechanism of growth differences between bud mutant of Zhonghong poplar and Quanhong poplar varieties and wild poplar,we used Zhonghong poplar( Populus deltoides Zhonghong,ZHP) originating from the bud sports of L2025 poplar and Quanhong poplar( Populus deltoids Quanhong,QHP) originating from the bud sports of ZHP and the green-leaf wild type L2025 to compare their chloroplast ultrastructure and photosynthetic characteristics. The results showed that the chloroplast basal laminas in the mesophyll cell of ZHP and QHP leaves were significantly decreased and chlorophyll biosynthesis was blocked. The blacked site might be located between Coprogen Ⅲand Proto Ⅸ,which further caused a significant decrease in photosynthetic pigments in the ZHP and QHP when compared to the wide type. Therefore,the photosynthesis capacities of the mutants were largely reduced,and the net photosynthetic rates were only 62% ~ 73% of the wide type poplar. This study theoretically confirmed the low growth of ZHP and QHP cuttings in production,which provides a certain reference for the promotion and production of colorleaved poplar varieties.