华南地区3个棕榈藤种光合途径的判别

C3植物uT以通过转入C4植物基因而具备C4植物光合特性,从而提高产量.有鉴于此,本文通过测定我国华南地区分布的黄藤(Daemonorops margarttae(Hance)Becc.)、单叶省藤(Calamus simplicifolius C.F.Wei)和白藤(C.tetradactylus Hance)等3个棕榈藤种苗木和成年植株叶片的叶绿素含量、气孔密度、磷酸烯醇式丙酮酸羧化酶(phosphoenolpyruvate carboxylase,PEPC)、丙酮酸磷酸二激酶(pyruvate phosphate dikinase,PPDK)和稳定碳同位素比值等指标以判别3个藤种的光合途径,为棕榈藤转入C4植物基因工作提供理论依据.结果表明,3种藤种苗木和成年植株的叶绿素含量和气孔密度比常见C3植物和C4植物高,但叶绿素a/b值、叶片上下表面气孔比值、PEPC酶活性、PPDK酶活性和稳定碳同位素比值等指标均较低,与常见C3植物的对应指标相当或略低,而远小于常见C4植物,因此认为黄藤、单叶省藤和白藤等3个藤种是C3植物.

Photosynthetic Pathway of Three Rattan Species in South China

Incorporating C₃ plants with C₄ photosynthesis traits by genetic engineering are available for improving plant productivity. Although rattans are a special and big group of plants including 13 genera and ca. 600 species in the world and have been studied since the mid-nineteenth century, the knowledge of its photosynthetic pathway is still lacking. Therefore, it is meaningful to determine the photosynthetic pathway of rattans. It was reported that chlorophyll a/b value, ratio of stomata occurrence on upper to lower epidermis, activities of phosphoenolpyruvate carboxylase (PEPC) and pyruvate phosphate dikinase (PPDK), and stable carbon isotope ratio in leaves of C₃ plants were lower than those of C₄ plants, thus this study tested them with seedlings and adult plants of the three rattan species, Daemonorops margaritae (Hance) Becc., Calamus simplicifolius C. F. Wei and C. tetradactylus Hance occurring in South China. The results showed that values of these indices were rather low, falling into the ranges of other C₃ plants, so it was concluded that three rattan species were C₃ plants.