不同繁育系统的榕树雌花的花柱长度和繁殖率比较  

COMPARISON OF STYLE LENGTH AND REPRODUCTION SUCCESS IN FICUS OF DIFFERENT BREEDING SYSTEMS

作　　者：马文娟[1,2] 张凤萍[1,2] 彭艳琼[1] 杨大荣[1] 

机构地区：[1]中国科学院西双版纳热带植物园,昆明650223 [2]中国科学院研究生院,北京100049

出　　处：《植物生态学报》2009年第5期911-918,共8页Chinese Journal of Plant Ecology

基　　金：国家自然科学基金(30571507和30670358);中国科学院知识创新工程青年人才领域前沿项目

摘　　要：多年来,不同繁育系统的榕树(Ficus spp.)的进化问题引起生物学家们极大的兴趣。前人通过对不同繁育系统榕树雌花的花柱长度、传粉榕小蜂产卵器长度和繁殖率的比较,推测榕树的雌雄异株是由雌雄同株进化而来的。为验证这一推论,选取雌雄同株的垂叶榕(Ficus benjamina)和钝叶榕(F.curtipes)以及雌雄异株的斜叶榕(F.tinctoria)和鸡嗉子榕(F.semicordata),进行了雌花花柱长度、传粉榕小蜂产卵器长度及繁殖率的比较。研究结果显示:1)两种雌雄同株榕树的传粉榕小蜂(Eupristina koningsbergeri和Eupristina sp.)的产卵器长度,显著长于两种雌雄异株榕树的传粉榕小蜂(Liporrhopalum gibbosae和Ceratosolen gravelyi)产卵器的长度,且雌雄同株榕树雌花花柱长度的变异大于雌雄异株雌花花柱长度的变异;2)两种雌雄同株榕树的雌花花柱长度呈单峰分布,且花柱长度的变异大于传粉榕小蜂产卵器长度的变异;两种雌雄异株榕树花序的雌花花柱长度呈双峰分布,雌花花柱长度的变异也大于传粉榕小蜂产卵器的长度变异;3)两种雌雄同株榕树的传粉榕小蜂产卵器长度能到达雌花子房的比例更高,可更有效地产生瘿花,而雌雄异株榕树产生种子的优势更强。研究表明:在传粉榕小蜂产卵器长度及花序雌花花柱分布方面,雌雄异株榕树有着明显的优势,但在繁殖率方面没有绝对优势。因此,前人从雌花花柱分布及繁殖率比较而做出榕树进化的推测并不正确。要真正解决榕树的进化问题,需要多学科、多指标的综合分析和深入研究。Aims Figs and fig wasps are classical materials for research on plant-animal coevolution. There are both monoecious and dioecious figs. The evolutionary mechanism of Ficus has attracted many biologists. Most recently,Chen （2005） deduced that Ficus evolved from monoecious to dioecious,based on comparison of style distribution,pollinators ovipositor length,and reproduction success in monoecious and dioecious figs. Our objective was to test the duduction and further study Ficus evolution. Methods We collected figs in the female floral phase and measured the length of styles and pollina- tors＇ ovipositors in both monoecious figs and dioecious figs using dissecting microscopy. Figs in the male florets phase were also collected. We counted （i） seeds, galls, bladders, and unparasitized ovaries for monoecious figs, （ii） galls, bladders, and unparasitized ovaries for dioecious male figs, and （iii） seeds and unparasitized ovaries for female figs. Important findings Ovipositor length was significantly longer, and the coefficient of variation （CV） of style length was higher in the two monoecious figs than in dioecious figs. Style length had unimodal distributions in the two monoecious figs, and their CVs were higher than pollinators＇ ovipositor length CVs. The style length had biomodal distributions in the two dioecious fig species, and the CVs of style length were also higher than those of the ovipositor length. Monoecious figs were more effective in producing galls, based on the proportions of ovaries that pollinators＇ ovipositors could reach, but dioecious figs were more effective in producing seeds. Therefore, the deduction of Chen （2005） is not completely correct, and additional research is needed to resolve the Ficus evolution question.

关 键 词：不同繁育系统榕树 花柱分布 产卵器 种子瘿花比例 繁殖率 

分 类 号：Q948[生物学—植物学]