珍稀濒危植物瑶山苣苔开花生物学及繁育系统研究  

Flower Phenology and Breeding System of Rare and Endangered Dayaoshania cotinifolia

作　　者：王玉兵[1,2] 梁宏伟[2] 莫耐波 覃康平 汤庚国[1] 

机构地区：[1]南京林业大学森林资源与环境学院,南京210037 [2]三峡大学,湖北宜昌443002 [3]广西壮族自治区金秀老山自然保护区,广西金秀545004

出　　处：《西北植物学报》2011年第5期958-965,共8页Acta Botanica Boreali-Occidentalia Sinica

基　　金：国家自然科学基金(31000146)

摘　　要：对仅分布于广西金秀老山自然保护区的国家Ⅰ级保护植物瑶山苣苔进行了开花生物学和繁育系统研究.结果显示：（1）瑶山苣苔花期从8月底至11月初,开花无固定时间.单花开放过程可分为萌动、露白、盛开、凋落4个阶段,且花朵具明显的增大再生长现象.（2）单花、花序、单株水平上的开花物候都表现出开花不同步性,单花花期约5-14 d,单花序花期约11-20 d,单株花期约8-20 d.花粉活力在散粉后6 d内相对较高,但花粉在野外通常于散粉3 d内被昆虫啃食完.（3）柱头在花药散粉时明显高于花药,便于接受异花花粉,柱头在散粉后第4天具可授性,可持续5-6 d.（4）瑶山苣苔杂交指数（OCI）为5,花粉-胚珠比（P/O）为379.64±145.61,繁育系统为兼性异交,自交亲和,传粉过程需要传粉媒介.研究表明,不稳定的传粉环境可能是该物种至濒的主要生殖生物学原因,自发自交＂是其在开花期间对不稳定传粉环境的一种适应.Dayaoshania cotinifolia W.T.Wang is one of the first class key protected wild plants of China,its flowering phenology features and breeding system were investigated in Jinxiu Laoshan Nature Reserve in Guangxi.The results showed that flowering of D.cotinifolia took place from late August to early November and there is no fixed-time for flowering in one day.The flowering process could be divided into four stages,such as budding dates,petal whiten,blooming and wither,the size of flowers had obvious increase duration of fowering.The flowering phenology manifested a profoundly asynchronization among single flower,single inflorescence as well as individual.The flowering process of single flower lasted 5~14 days,the single inflorescence lasted 11~20 days,while anthesis of individual lasted about 8~20 days.The pollen viability was relatively high in 6 days after pollen dissemination,but pollen was eat up by insect in field within 3 days after dissemination.The stigma was obviously higher than the anther when pollen dissemination,which easily made it to be received allogamy.The stigma had receptivity after 4 days of pollen dissemination,and could last 5 or 6 days.The outcrossing index and pollen-ovule ratio of D.cotinifolia were 5 and 379.64±145.61,respectively.The breeding system is outcrossing with partial self-compatibility,needing pollinators.Unstable pollination environment maybe the major factor leading to the endangered status of D.cotinifolia in reproduction,＇autonomous selfing＇ adapts to unstable environment during the blooming season.

关 键 词：瑶山苣苔 开花动态 传粉 繁育系统 

分 类 号：Q944.4[生物学—植物学]