摘要
堇叶紫金牛是一种特产于浙江和台湾的珍稀濒危植物.为了解堇叶紫金牛对光的需求及适应规律,本文研究了不同光照强度(遮阴率90%、60%、25%及全光照)对其光合特性和叶绿素荧光参数的影响.结果表明:全光照条件下堇叶紫金牛净光合速率(Pn)、气孔导度(gs)日变化曲线均呈"双峰型",出现光合"午休现象",而遮阴处理下均呈"单峰型".随遮阴率的增加,堇叶紫金牛叶片Pn和表观量子效率(AQY)均呈先升高后降低的趋势,光饱和点(LSP)和光补偿点(LCP)均呈降低趋势,gs、蒸腾速率(Tr)、原初光能转换率(Fv/Fm)和PSⅡ潜在活性(Fv/Fo)均呈升高趋势.遮阴造成叶绿素总量、类胡萝卜素(Car)含量的增加和Chl a/b的降低.遮阴率25%条件下,堇叶紫金牛根冠比(R/T)和比叶重(LMA)均达到最大值.堇叶紫金牛对不同光环境表现出较强的适应性和可塑性,表明光照不足不是其野外种群致濒的主要原因.
Ardisia violacea is one of the rare and endangered species, and distributes only in Zhe- jiang and Taiwan Provinces in China. In order to understand the light requirement and adaptability of A. violacea, the effects of different light intensities （shading rate of 90%, 60%, 25%, and the full light） on leaf photosynthetic characteristics and chlorophyll fluorescence of A. violacea were studied. The photosynthetic rate （P,） and stomatal conductance （gs） of A. violacea varied as a bi- modal curve with a ＇midday depression＇ phenomenon in full bright light, and as a unimodal curve in the shading treatments. With the increasing shading rate, the Pn and apparent quantum efficiency （AQY） first increased, and then decreased, the light compensation point （LCP） and light satura- tion point （LSP） decreased, and the gs, transpiration rate （Tr）, original light energy conversion （ Fv/Fm ） and potential activity of PS 11 （ Fv/Fo ） increased. The total quantity of chlorophyll and the carotenoid （Car） content increased, and Chl a/b decreased under shading conditions. When the shading rate was 25%, the specific leaf mass （LMA） and root to shoot （R/T） ratio of A. viola- cea reached the maximum. A. violacea possessed a strong flexibility to different light environments, suggesting that light could not be the main limiting factor for natural regeneration of A. violacea populations.
出处
《应用生态学报》
CAS
CSCD
北大核心
2014年第7期1940-1948,共9页
Chinese Journal of Applied Ecology
基金
浙江农林大学科研发展基金项目(2008FK53)
国家自然科技资源平台项目(2005DKA21403)
浙江省重大科技攻关项目(2006C12059-2)资助
关键词
堇叶紫金牛
遮阴
光合特性
叶绿素荧光
Ardisia violacea
shade
photosynthetic characteristics
chlorophyll fluorescence.
作者简介
张云，女，1988年生，硕士研究生．主要从事野生植物资源引种及开发利用研究．E—mail：sweets-2008@163．com
通讯作者．E—mail：zjfc_ghxia@126．com
