作 者 ：柴胜丰1,2,庄雪影2,韦 霄1*,王满莲1,唐建明3,陈宗游1
期 刊 ：西北植物学报 2013年 3期 页码：547~554
Keywords:Camellia pubipetala, endangered plant, light intensity, photosynthetic characteristics,
摘 要 ：以盆栽3年生毛瓣金花茶实生苗为材料,采用人工遮荫方法研究不同光照强度（10％、25％、50％和100％自然光强）对其光合生理特性的影响,为其迁地保护和种群恢复提供科学依据。结果显示:（1）随着光照强度的升高,毛瓣金花茶叶片最大净光合速率（Pmax）、表观量子效率（AQY）和光饱和点（LSP）降低,光补偿点（LCP）升高,其中Pmax和AQY在10%和25%光强下显著高于50%和100%光强处理。（2）叶片叶绿素总量（Chl）、叶绿素a（Chl a）、叶绿素b（Chl b）、类胡萝卜素（Car）含量均随光强的升高而降低,Car/Chl含量随光强的升高而升高。（3）叶绿素荧光参数Fm、Fv、Fv/Fm、Fv/F0均随光强的升高而降低,其中Fm、Fv、Fv/Fm在100%光强下显著低于其他3个遮荫处理,3个遮荫处理间则无显著差异。（4）叶片丙二醛（MDA）和脯氨酸（Pro）含量均随光强的升高而升高,在100%光强下,MDA和Pro含量显著高于其他3个遮荫处理,50%光强下的MDA含量显著高于10%和25%光强处理。（5）在25%光强下,毛瓣金花茶未发生明显光抑制,在50%光强下,其光抑制主要是由PSⅡ的可逆失活引起的,光合机构未遭到明显破坏,在100%光强下,其PSⅡ反应中心受到严重伤害,发生了光氧化。研究表明,毛瓣金花茶虽为阴生植物,却能忍受一定程度的强光（50%光强）,在种群恢复过程中,可适当间伐上层乔木,增加林下透光率,提高毛瓣金花茶种群的开花结实率,促进其自然更新,在迁地保护时可选择相对开敞的遮荫环境。
Abstract:Potted 3-year-old seedlings of Camellia pubipetala were grown in 10%,25%,50% and 100% natural light intensity,and the effects of light intensity on photosynthesis and physiological characteristics of C.pubipetala seedlings were studied.It will provide scientific basis for ex-suit conservation and population recovery in C.pubipetala.(1)It has been found that with the increasing light intensity,the maximum net photosynthetic rate (Pmax),light saturation point (LSP) and apparent quantum yield (AQY) all decreased,while light compensation point(LCP) increased.The Pmax and AQY in 10% and 25% light were significantly higher than that in 50% and 100% light.(2)The contents of total chlorophyll (Chl),chlorophyll a (Chl a),chlorophyll b (Chl b) and carotenoid (Car) in leaves all decreased with increasing light intensity,while Car/Chl enhanced with stronger irradiance.(3)The chlorophyll a fluorescence parameters Fm,Fv,Fv/F0,Fv/Fm all decreased under high light,and Fm,Fv,Fv/Fm in 100% light were significantly lower than that in other three treatments,while these 3 parameters had no significantly difference in 10%,25%,50% light.(4)The contents of malondialdehyde (MDA) and proline (Pro) in leaves increased in strong light,and in 100% light,these two indexes were significantly higher than that in other three treatments,the contents of MDA in leaves was significantly higher in 50% light than that in 10% and 25% light.(5)There was no photoinhibition in 25% natural light intensity of C.pubipetala.While in 50% natural light intensity,its photoinhibition was mainly caused by reversible deactivation of PSⅡ reaction center.In 100% natural light intensity,the reaction center of PSⅡ was seriously destroyed,and there was a light oxidation in C.pubipetala.We concluded that C.pubipetala is a shade-tolerant plant,but it can bear a certain degree of strong light (50% light intensity).So the protect measure of moderate intermediate cutting upper layer trees could be adopted in over crown closure forest so as to increase forest light transmittance,which improve flowering and seed setting rate of the plant,and promote the natural regeneration of C.pubipetala population.C.pubipetala is suitable for growing in opening shade environments in ex-suit conservation.