珙桐(Davidia involucrata Baill.)苞片功能性状及性状间关系对海拔的响应  

Altitudinal changes of functional traits and relationships among traits of bracts in dove tree(Davidia involucrata Baill.)

作　　者：刘婷婷[1] 刘沁松 徐文娟 徐治兵 李中阳 杨宝臻 胥晓[1,2] LIU Ting-ting;LIU Qin-song;XU Wen-juan;XU Zhibing;LI Zhong-yang;YANG Bao-zhen;XU Xiao(Key Laboratory of Southwest China Wildlife Resources Conservation(China West Normal University),Ministry of Education,Nanchong 637009,Sichuan,China;College of Life Science,China West Normal University,Nanchong 637009,Sichuan,China)

机构地区：[1]西南野生动植物教育部重点实验室,四川南充637009 [2]西华师范大学生命科学学院,四川南充637009

出　　处：《生态学杂志》2020年第3期794-802,共9页Chinese Journal of Ecology

基　　金：国家自然科学基金项目(31900277);西华师范大学英才基金(17Y351)资助。

摘　　要：珙桐(Davidia involucrata Baill.)的苞片被认为是对传粉者和非生物因素等驱动力的适应,往往受到环境因子的影响。为揭示其功能性状及其性状间关系对海拔的响应,本研究采用独立样本t检验和标准化主轴分析方法对比了四川龙苍沟1400和1800 m不同海拔珙桐种群中花苞片的功能性状和性状间关系。结果显示:1)低海拔(1400 m)珙桐种群大、小苞片的长、宽和面积,以及单花苞片总面积均显著大于高海拔(1800 m)种群(P<0.05),且高、低海拔种群的大、小苞片面积及重量呈等比例生长;2)低海拔珙桐种群大、小苞片干重及单花苞片总干重均显著高于高海拔种群(P<0.05);3)高、低海拔种群的花序轴长与干重均无显著差异(P=0.446;P=0.791),高海拔花序轴干重与长间呈异速生长关系,而低海拔呈等速生长关系;4)珙桐大、小苞片的长宽间、面积间以及重量间关系在高、低海拔上均表现出等速生长,单花苞片的总面积和总干重分别与花序轴干重在高、低海拔上均表现出等速生长关系,而与花序轴长表现出异速生长关系。上述结果表明,珙桐苞片的功能性状及其性状间关系在不同海拔存在显著差异,这种现象可能是其在长期进化过程中抵抗环境干扰、保护繁育器官和提高授粉几率而形成的一种适应策略。Bracts of dove tree(Davidia involucrate Baill.)are adaptive to the driving forces of pollinators and abiotic factors,which are sensitive to environmental factors.To reveal the changes of functional traits and their relationships across different altitudes,the independent-sample t test and standardized major axis estimation were used to examine the functional traits and relationships of bracts in dove trees at 1400 m and 1800 m in Longcanggou,Sichuan.The results showed that:(1)Length,width and area of large and small bracts,as well as the total area of single flower bract in the population from low altitude(1400 m)were significantly larger than that from high altitude(1800 m)(P<0.05),while area and mass of large and small bracts in high and low altitude populations grew in proportion.(2)The mass of the large and small bracts and the total mass of the single flower bract in the population from low altitude(1400 m)were significantly higher than those from high altitude(1800 m)(P<0.05).(3)There was no significant difference in the length and the mass of inflorescence axis between high and low altitude populations(P=0.446;P=0.791).There was an allometric relationship between the mass of the inflorescence axis and the length at high altitude,but an isometric relationship at low altitude.(4)Therelationships between length,width,area and mass of bracts showed isometric relationships at high and low altitudes.The total area and the total mass of single flower bract showed an isometric growth relationship with the mass of inflorescence axis at high and low altitudes,but showed an allometric growth with the length of inflorescence axis.In all,our results highlighted differences in the functional traits and the relationships between traits of bracts in dove tree at different altitudes,which may be an adaptive strategy to resist environmental interference,protect reproductive organs,and improve pollination rate.

关 键 词：珙桐 花序轴 性状 异速生长 繁殖器官 

分 类 号：S792.99[农业科学—林木遗传育种]