霍山县3种石斛叶片光合特性及其对光强的响应

Leaf photosynthetic characteristics and its response for light intensity of three species of Dendrobium Sw.in Huoshan County

目的研究石斛的光合特性,了解其适宜栽种的光强。方法测定霍山县3种石斛(霍山石斛Dendrobiumhuoshanens,铁皮石斛D.candium,铜皮石斛D.moniliforme)的光合速率对光强响应曲线,不同光强处理时叶绿素荧光参数的变化及3.0×104lx瞬时光强下叶片荧光猝灭诱导。结果霍山县3种石斛属于阴生植物对光强的响应,光饱和点、光补偿点较低,净光合速率和表观量子效率都较低;大于4.0×104lx强光下石斛叶片受光抑制严重。结论霍山县3种石斛生长光强,一般为(0.2～2.0)×104lx;可以在(2.5～3.0)×104lx光强的环境中生长;不适宜在大于4.0×104lx光强的环境中生长。

Objective To investigate the suitable light intensity of plant growth of Dendrobium Sw.through study on photosynthetic characteristics.Methods The photosynthesis curves of light intensity, chlorophyll fluorescence parameter of different light intensity and inductivity of non-photochemical quenching of chlorophyll fluorescence in 3.0×104 lx on three species of Dendrobium Sw.in Huoshan (D.huo- shanens, D.candium, and D.moniliforme) were determined.Results Three species of Dendrobium Sw.were shadow plants for their response on light intensity, light saturation point, light compensate point, net photosynthesis rate, and apparent quantum efficiency are lower during photosynthesis.The photoinhibitory effect was formed on Dendrobium Sw.leaf when they grew in more than 4.0×104 lx.Conclusion Although three species of Dendrobium Sw.in Huoshan grow in (0.2-2.0)×104 lx normally, they are suitable to grow in (2.5-3.0)×104 lx instead of growing more than 4.0×104 lx.