遮阴处理条件下艾纳香的光合特性研究

目的]研究遮阴处理条件下艾纳香的光合特性。方法]在盆栽条件下,以1层(7%～10%)、2层(15%～20%)、4层(30%～40%)3种不同遮阴处理的艾纳香叶片为对象,用Li-6400型便携式光合作用测定系统对其叶片光合作用日变化、光响应曲线进行比较测定,阐述光合作用对艾纳香光浓度的响应特征。结果]1层遮阴艾纳香叶片的光合速率(Pn)日变化呈双峰曲线型,峰值在10:30和13:30,"谷底"出现在12:30,有明显的"午休"现象;2层遮阴和4层遮阴的艾纳香光合作用微弱,整个白天一直在0值附近上下波动。艾纳香药用植物光合速率值大小顺序为1层遮阴艾纳香>2层遮阴艾纳香>4层遮阴艾纳香;光合速率(Pn)响应的大小顺序为1层遮阴艾纳香>2层遮阴艾纳香>4层遮阴艾纳香。结论]1层遮阴艾纳香的光合速率值明显高于其他2种光照处理,表现出明显的高光合效率特性;叶片对不同强度光合有效辐射的光响应特征有明显差异。

Photosynthetic Characteristics of Blumea balsamifera Under the Condition of Shading Treatment

Objective] To study the photosynthetic characteristics of Blumea balsamifera(Linn.) DC under the condition of shading treatment.Method] Under pot culture,B.balsamifera leaves with 1(7%-10%),2(15%-20%),and 4(30%-40%) layers of shading were studied.Li-6400 portable photosynthesis system was used to detect and compare the photosynthesis daily change of leaves,and the response curve.Photosynthetic characteristics of photosynthesis to the light concentration of B.balsamifera were studied.Result] Daily change of photosynthetic rate(Pn) in one layer shading treatment showed double-peak curve;while the photosynthesis in 2-layer and 4-layer treatment were relatively weak,and fluctuated around 0 in the whole daytime.Photosynthetic rates of B.balsamifera in three treatments were in the order of 1-layer shading > 2-layer shading > 4-layer shading.The responses of photosynthetic rate(Pn) were in the order of 1-layer shading > 2-layer shading > 4-layer shading.Conclusion] Photosynthetic rate of1-layer shading of B.balsamifera was significantly higher than other 2 shading treatments,showing significant characteristics of high photosynthetic rate.Leaves had different photoresponse characteristics to different photosynthetic active radiations.