不同生长时期泽泻蕨叶片光响应曲线的研究

The Research of Light Response Curve of Parahemionitis Cordata Leaf in Different Growth Period

为探索人工栽培过程中泽泻蕨营养生长期和生殖生长期对光强的不同需求,运用气体交换法研究了以上两个时期泽泻蕨叶片的光响应曲线及相关参数,并选取了适用于泽泻蕨的光响应曲线模型.结果表明:泽泻蕨营养生长期和生殖生长期叶片的光响应曲线趋势相似,营养生长期的表观光量子效率大于生殖生长期,差异不显著,最大净光合速率和光饱和点显著大于生殖生长期,暗呼吸速率、光补偿点等指标均与生殖生长期差别不大;在泽泻蕨双曲线模型的拟合方面双曲线修正模型较其他常用模型更为精确.实验认为泽泻蕨营养生长期叶片较生殖生长期更适应弱光环境,且具有较低的光饱和点,可能在高光强更易出现光抑制.

In order to study the photo -physiological characteristics of vegetative leaves of the ferns Parahemionitis cordata during vegetative growth and reproductive growth, the photosynthesis - light （Pn - PAR） curves were determined in gas- exchange method by LI -6400 Portable Photosynthesis System. The result showed that： light response curve （Pn -PAR curve ） during both the vegetative growth and reproductive growth have a Sigmoid Curve; the maximum photosynthesis （Pmax） and light satisfied point （LSP） of vegetative growth were higher than the reproductive growth. Light compensation point （LCP） of vegetative growth were lower than the reproductive growth. The modified rectangular hyperbola model could be more suitable for Parahemionitis cordata in P,, -PAR curve fitting. In this paper, these aspects are suggested that Parahemionitis cordata leaves during vegetative growth have lower LSP, and could grow better in dim light compare with leaves of reproductive growth; therefore they may easier get photo - inhibition under strong light.