乡土珍贵树种钩栗幼苗种源间光合生理特性研究  

Photosynthetic traits of the precious native species of Castanopsis tibetana seedlings among different provenances

作　　者：王佩兰[1] 康华荣 李柏海[3] 李志辉[1] 张斌[1] 吴毅[1] 

机构地区：[1]中南林业科技大学林学院,湖南长沙410004 [2]汨罗市林业局,湖南汨罗414400 [3]湖南省森林植物园,湖南长沙410116

出　　处：《中南林业科技大学学报》2016年第3期38-45,共8页Journal of Central South University of Forestry & Technology

基　　金：国家林业行业公益性行业专项(201204405);中南林业科技大学科技创新基金项目(CX2013B30);湖南省林业科技创新计划资助项目(XLK201424)

摘　　要：利用Li-6400光合仪对湖南浏阳、桑植、永顺、福建建瓯和湖北恩施等5个不同地理种源的钩栗1 a生幼苗在春、夏、秋、冬4个季节里的光合生理指标进行测定,探讨钩栗光合能力的季节变化及其对不同光环境的响应,分析珍稀树种日趋减少的原因及保护措施,为钩栗的良种选育与迁地保护提供了重要的理论依据。结果表明:钩栗的净光合速率(P_n)日变化在春季、夏季和秋季3个季节中呈现为"双峰"曲线,在冬季则呈现为"单峰"曲线,4个季节钩栗的日均Pn值均表现为夏季>秋季>春季>冬季,5个钩栗种源的光合能力强弱顺序为:恩施>桑植>永顺>浏阳>建瓯。钩栗的光补偿点(LCP)、光饱和点(LSP)、表观量子效率(AQY)、暗呼吸效率(R_d)和最大净光合速率(P_(nmax))均表现为夏季>秋季>春季>冬季,且夏季光合优势明显。钩栗的光合能力在生理上具有一定的可塑性,具有阳性树种的特点。恩施种源的LCP、LSP、AQY、R_d和P_(nmax)在4个季节中均表现为最大,这表明恩施种源是光合能力最强的种源。A portable Li-6400 photosynthesis measuring system was used to explore how Castanopsis tibetana, an precious native species to China, adapts to the environment and to illustrate and determine various photosynthetic characteristics of Castanopsis tibetana. Taking one-year seedling of Castanopsis tibetana from different geographical provenance of Liuyang, Sangzhi, Yongshun Hunan, Jian＇ou Fujian and Enshi Hubei, as material, Some photosynthetic parameters were dynamicly monitored. Also, the physiological mechanisms that have resulted in the endangered status of this species were explored to provide baseline reference data in support of off-site conservation and population rejuvenation of Castanopsis tibetana. The results for Castanopsis tibetana show that when the diurnal variation in the photosynthetic rates in the spring, summer and autumn are graphed, typic al curves with double peaks appear; in addition, photosynthetic rates in the winter shows curves with a single peak as do photosynthetic rates of five provenance based on data in all four seasons. The net photosynthetic rate（P_（nmax））, light saturation point（LSP）, Light saturation point（LCP）, apparent quantum yield（AQY） and Dark respiration（R_d）, were highest in summer of all provenance; this indicates the photosynthetic capacity of Castanopsis tibetana is significantly higher in summer than in other seasons. As a result, In all four seasons the daily mean values of Pn, P_（nmax）, LSP, LCP, AQY and R_d of Enshi provenace are higher with significant differences than the other provenance. These findings indicate that the photosynthetic characteristics of Castanopsis tibetana are typical for a plant growing in sunny habitats and Enshi provenance is the best provenance.

关 键 词：乡土珍贵树种 钩栗 种源 光合特性 

分 类 号：S792.17[农业科学—林木遗传育种]