极小种群野生植物十万大山苏铁幼苗的光合生理特性  

Photosynthetic Characteristics of Wild Plant Species With Extremely Small Populations Cycas shiwandashanica

作　　者：唐健民 秦惠珍 邹蓉[1] 朱成豪 韦霄[1] 蒋运生[1] 熊忠臣[1] Tang Jianmin;Qin Huizhen;Zou Rong;Zhu Chenghao;Wei Xiao;Jiang Yunsheng;Xiong Zhongchen(Guangxi Key Laboratory of Functional Phytochemicals Research and Utilization,Guangxi Institue of Botany,Guangxi Zhuang Autonomous Region and Chinese Academy of Sciences,Guilin,541006)

机构地区：[1]广西壮族自治区中国科学院广西植物研究所,广西喀斯特植物保育与恢复生态学重点实验室,桂林541006

出　　处：《分子植物育种》2021年第11期3756-3762,共7页Molecular Plant Breeding

基　　金：广西自然科学基金(2020GXNSFAA259029);中央引导地方科技发展专项资金(桂科ZY1949013);广西植物研究所所基本业务费(桂植业18013;桂植业18014和桂植业19002)共同资助。

摘　　要：十万大山苏铁(Cycas shiwandashanica)属于苏铁科(Cycadaceae)苏铁属(Cycas)植物,因其生境破碎,野生资源稀少,被列为极小种群。目前缺乏对其野生资源的群落结构调查与栽培研究。本研究以十万大山苏铁幼苗为研究对象,测定其一年生、二年生幼苗的生长指标,并采用Li-6400便携式光合仪测定一年生幼苗的光合日变化和光合响应曲线。结果表明,十万大山苏铁一年生幼苗与二年生幼苗的苗高、地径和冠幅显著增加,生长良好。十万大山苏铁净光合速率Pn日变化为双峰曲线,两个峰值出现在上午10:30和下午14:30,净光合速率分别为1.73μmol•m^(-2)•s^(-1)和1.76μmol•m^(-2)•s^(-1),没有出现光合午休现象,净光合速率受到气孔因素和非气孔因素限制。十万大山苏铁的光补偿点(LCP)为3.68μmol•m^(-2)•s^(-1)、光饱和点(LSP)为1023.67μmol•m^(-2)•s^(-1),最大光合速率(Pmax)为3.57μmol•m^(-2)•s^(-1),属于中生植物。本研究通过测定十万大山苏铁的生长势和光合特性,首次揭示了该植物的光合生理特性,为十万大山苏铁的保护及引种栽培提供技术支撑和缓解十万大山苏铁的濒危状态提供理论支持,对十万大山苏铁的保护研究具有理论价值和指导意义。Cycas shiwandashanica is classified as an extremely small populations of cycads due to its fragmented habitat and scarce wild resources.The growth indexes of annual and biennial seedlings from Cycas shiwandashanica were determined,and diurnal photosynthetic changes and photosynthetic response curves of Annual seedlings were measured by Li-6400 portable photosynthetic apparatus.The results showed that the seedling height,ground diameter and crown width of the biennial seedlings were significantly higher than those of the annual seedlings,it can be grown well in this habitation.The daily change of net photosynthetic rate Pnof Cycas shiwandashanica was bimodal curve,with the two peaks appearing at 10:30 am and 14:30 pm,and the net photosynthetic rates were1.73μmol·m^(-2)·s^(-1) and 1.76μmol·m^(-2)·s^(-1),respectively,and the net photosynthetic rate was limited by stomatal factors and non-stomatal factors.It belongs to the mesophytic plant,with a light compensation point(LCP)of 3.68μmol·m^(-2)·s^(-1),a light saturation point(LSP)of 1023.67μmol·m^(-2)·s^(-1) and a maximum photosynthetic rate(Pmax)of 3.57μmol·m^(-2)·s^(-1).This study by measuring the growth potential and photosynthetic characteristics,reveals the photosynthetic characteristics of the Cycas shiwandashanica for the first time.It provides technical support for the protection,introduction and cultivation of Cycas shiwandashanica,provides theoretical support for the mitigation of the endangered status of Cycas shiwandashanica,and has theoretical value and guiding significance for the protection research of it.

关 键 词：十万大山苏铁(Cycas shiwandashanica) 极小种群野生植物 日变化 光响应曲线 生长势 

分 类 号：Q945.11[生物学—植物学]