基于^(13)C示踪的2个杉木家系幼苗光合碳分配动态  

Dynamics of Photosynthetic Carbon Allocation in Seedlings of Two Chinese Fir Families Based on ^(13)C Tracing

作　　者：杨梦佳 邹显花 郭志娟 彭钊 何妍 彭志远 姚必达 黄国敏[1] 朱丽琴[1] 黄荣珍[1] Yang Mengjia;Zou Xianhua;Guo Zhijuan;Peng Zhao;He Yan;Peng Zhiyuan;Yao Bida;Huang Guomin;Zhu Liqin;Huang Rongzhen(Jiangxi Key Laboratory for Intelligent Monitoring and Integrated Restoration of Watershed Ecosystem Nanchang University of Technology,Nanchang 330099;Shenzhen Shiyuan Engineering Technology Co.,Ltd.,Shenzhen 518103)

机构地区：[1]南昌工程学院流域生态智能监测与综合治理江西省重点实验室,南昌330099 [2]深圳世源工程技术有限公司,深圳518103

出　　处：《林业科学》2024年第12期35-46,共12页Scientia Silvae Sinicae

基　　金：国家自然科学基金地区基金项目(32160361);赣鄱俊才支持计划-主要学科学术和技术带头人培养项目——青年人才(20232BCJ23043);南昌工程学院大学生创新创业训练计划项目(S202411319009,省级);南昌工程学院2021年引进高层次人才科研启动项目(2021kyqd002)。

摘　　要：【目的】探究2个杉木家系幼苗在不同CO_(2)浓度下对外源碳的固定及其光合碳在不同器官中的运输与分配规律,为揭示杉木固碳及光合碳分配策略对CO_(2)浓度升高的响应机制提供理论依据。【方法】以南方林区广泛种植的洋口No.020和No.061杉木幼苗为对象,设置对照CO_(2)浓度(400±50)μmol·mol^(-1)(C400)及CO_(2)浓度分别升高到(800±50)μmol·mol^(-1)(C800)和(1000±50)μmol·mol^(-1)(C1000)这3个CO_(2)浓度梯度,利用^(13)C标记法对不同浓度CO_(2)进行标记,量化示踪标记后不同阶段各杉木家系幼苗固定的光合碳在各组织器官的流向和分配,分析幼苗净光合速率、各器官生物量分配比例及生长差异,阐明不同CO_(2)浓度条件下各杉木家系幼苗的固碳能力及光合碳的体内分配规律差异。【结果】在不同CO_(2)浓度处理下,各杉木家系幼苗的各组织器官的^(13)C分配和生物量分配比例均大致呈现叶>茎>根的规律。随着CO_(2)浓度增加,各杉木家系幼苗的净光合速率与各器官δ^(13)C值总体上随之增加;No.020加快对根的^(13)C运输,表现为处理1天后,C800与C1000处理下根的^(13)C分配比例分别较C400处理增加50.40%和109.63%。CO_(2)处理浓度亦影响各杉木家系幼苗的光合碳分配策略,进而改变生物量分配。30天后,相较C400处理:C800与C1000处理下的No.020地上部^(13)C分配比例分别增加了6.23%和6.03%,No.020茎的^(13)C分配比例分别增加了39.50%和50.31%(P<0.05),No.061根系^(13)C分配比例分别增加了22.40%和70.26%(P<0.05),No.061茎的^(13)C分配比例分别减少了2.45%和15.10%(P<0.05);C1000处理下No.061茎的生物量分配比例减少12.44%,根的生物量分配比例增加5.22%。【结论】正常大气CO_(2)浓度下,No.020杉木幼苗具有更强的代谢转运能力。CO_(2)浓度升高促进2个杉木家系幼苗提高净光合速率,增加光合碳合成,促进No.020杉木幼苗加快对光合碳的向下运输,并影响2个�【Objective】To investigate the exogenous carbon fixation and photosynthetic carbon transport and allocation in different organs of seedlings of two Chinese fir families under different CO_(2) concentrations,and to provide a theoretical basis for revealing the response mechanism of carbon fixation and photosynthetic carbon allocation strategy to the increase of CO_(2) concentration.【Method】Three CO_(2) concentration gradients were established:a control concentration of(400±50)μmol·mol-1(C400)and two elevated concentrations of(800±50)μmol·mol^(-1)(C800)and(1000±50)μmol·mol^(-1)(C1000)were established in the seedlings of No.020 and No.061 Chinese fir,which are extensively cultivated in the southern forest region,with the objective of quantifying the flow and distribution of fixed photosynthetic carbon in diverse tissues and organs at varying stages following tracer labeling,employing the ^(13)C labeling method.The ^(13)C labeling method was employed to label varying concentrations of CO_(2),quantify the flow and distribution of fixed photosynthetic carbon in each tissue and organ at different stages of the tracer labelling process,and analyse the net photosynthetic rate.The objective is to ascertain the proportion of biomass distributed to each organ and to elucidate the growth differences.Furthermore,the aim is to determine the differences in carbon fixation capacity and the in vivo distribution of photosynthetic carbon in seedlings of each Chinese fir family under different CO_(2) concentration conditions.【Result】The ^(13)C allocation and biomass allocation ratios of all tissue organs in seedlings of each Chinese fir family exhibited a pattern of leaf>stem>root under different CO_(2) concentration treatments.As the CO_(2) labelling concentration increased,the net photosynthetic rate and δ^(13)C value of each organ in seedlings of each Chinese fir family generally increased subsequently.No.020 facilitated the transfer of ^(13)C to the roots,as evidenced by an increase in the latter.Following a

关 键 词：^(13)C标记 杉木 不同家系 CO_(2)浓度升高 光合碳分配 

分 类 号：S718.43[农业科学—林学]