摘要
不同传粉者类群可通过与花表型性状产生不同的互作进而影响植物个体的繁殖适合度。因此,在泛化传粉系统中,探究植物花表型对不同传粉环境的繁殖适应性对理解其进化选择机制具有重要意义。高寒草地狼毒(Stellera chamaejasme)拥有鳞翅目昆虫(蝶、蛾类)和缨翅目蓟马两类传粉者,该研究通过套袋操控形成开放授粉与仅蓟马授粉两种传粉环境,比较两类传粉功能群对狼毒繁殖成功的相对贡献,并探讨花性状对不同传粉环境的繁殖适应性。结果发现:狼毒表型性状在个体间存在不同程度的变异性;其中,花结构性状(花冠口大小和花管长)的变异较小,花产量性状(小花数)的变异系数居中,株丛大小(花序数)的变异系数最大。狼毒的结籽数及坐果率在两种授粉条件下均存在显著差异(P<0.001)。在开放授粉条件下,狼毒花序的结籽数和坐果率均显著高于仅依赖蓟马授粉的花序。花冠口大小、花管长以及两性状组合,在两种授粉条件下对狼毒繁殖适合度的影响存在显著差异:在开放授粉条件下,狼毒繁殖适合度(结籽数和坐果率)与花冠口大小存在显著正线性关系(P<0.01),与花管长度存在显著的负线性关系(P<0.01),与两种性状组合(交互)存在显著负相关关系(P<0.01);然而,仅在蓟马授粉条件下,两种性状单独对繁殖适合度的影响均不显著,但二者互作对狼毒繁殖适合度产生显著的正向影响(P<0.01)。花产量性状(小花数)在开放授粉环境下与结籽数之间存在显著的正线性关系(P<0.01),而仅在蓟马授粉环境下,二者均无显著相关性。在蓟马授粉条件下,株丛花序数对狼毒的(单花序)繁殖适合度产生显著的负向影响(P<0.05),而在开放授粉条件下,对其繁殖成功的影响不显著。本研究表明,狼毒的花结构及花展示性状可通过与传粉者互作影响繁殖成功,且对不同的传粉者功能群表现出分化适应趋向。
Different pollinator groups exert distinct effects on the reproductive fitness of plant individuals through specialized interactions with floral phenotypic traits.Therefore,in generalized pollination systems,investigating floral phenotype adaptation under different pollination environments is crucial to understand their evolutionary selection mechanisms.The alpine perennial Stellera chamaejasme is pollinated by two groups of insects,namely,lepidopterans(butterflies and moths)and thrips.By establishing two pollination treatments(i.e.,open pollination and thrips pollination)through bagging manipulation,this study determined the relative contributions of two pollinator functional groups to reproductive success of S.chamaejasme and examined the reproductive adaptation of floral traits under different insect pollination conditions.The results showed that the phenotypic traits of the plant showed variability of different degrees among individuals.Among these traits,the floral structural traits,such as corolla entrance diameter(i.e.,opening)and corolla tube length,showed relatively low coefficient of variation(CV),the flower production(i.e.,flower number per inflorescence)had a moderate CV,and the inflorescence number per plant displayed the highest CV.Both fruit set and seed number showed significant differences between the two pollination treatments(P<0.001).Under open pollination,both seed number and fruit set were significantly higher than those under thrips pollination.The effects of corolla opening,tube length and their interaction on reproductive fitness significantly differed between two pollination treatments.Under open pollination condition,the reproductive fitness(i.e.,seed number and fruit set)showed a significant positive linear relationship with corolla entrance diameter(P<0.01),a negative linear relationship with tube length(P<0.01),and a negative relationship with the interaction of the two traits(P<0.01).In contrast,under the thrips pollination condition,the two traits did not significantly affect reproductive fitness,but their interaction exerted a significantly positive effect on the fitness(P<0.01).The flower number per inflorescence exhibited a significant positive linear correlation with seed number under open pollination(P<0.01),whereas no significant correlation was detected under thrips pollination.The inflorescence number per plant exerted a significantly negative effect on the reproductive fitness of an inflorescence(P<0.05)under thrips conditions,while the effect was not statistically significant under open pollination.These findings suggest that the floral structural traits as well as floral display in S.chamaejasme can notably influence reproductive success of the plant through interactions with pollinators,exhibiting divergent adaptation to different functional groups of pollinators.
作者
窦嘉宁
张夺霖
袁宗琦
冷静
张建成
张文柳
张勃
DOU Jianing;ZHANG Duolin;YUAN Zongqi;LENG Jing;ZHANG Jiancheng;ZHANG Wenliu;ZHANG Bo(Key Laboratory of Grassland Ecosystem of Ministry of Education,the College of Grassland Science,Gansu Agricultural University,Lanzhou 730070,China)
出处
《生态学报》
北大核心
2026年第3期1265-1274,共10页
Acta Ecologica Sinica
基金
国家自然科学基金项目(31960349,32560925)。
关键词
狼毒
泛化传粉
变异性
繁殖成功
传粉者介导的选择
Stellera chamaejasme
generalized pollination
variation
reproductive success
pollinator-mediated selection
