《植物生理学报》 2017, 53(12): 2215-2221

圆齿野鸦椿开花动态特征与繁育系统

孙维红, 袁雪艳, 吴玲娇, 向双, 邹双全^*

福建农林大学林学院, 自然生物资源保育利用福建省高校工程研究中心, 福州350002

通信作者：邹双全；E-mail: 282014224@qq.com

摘　要：

为了解圆齿野鸦椿的开花特性及繁育系统, 本研究通过观测其花部特征、开花进程及访花昆虫特性, 采用离体培养法和联苯胺–过氧化氢法分别测定花粉活力和柱头可授性, 运用花粉/胚珠比(P/O值)、杂交指数(OCI值)、人工授粉试验等方法检测圆齿野鸦椿的繁育系统。结果表明, 圆齿野鸦椿花期为5月中旬至6月初, 其生殖枝聚伞花序的开花顺序为: 由上至下, 由内及外, 单花花期约为1 d; 两性花, 花小, 雄蕊5, 偶见4或6, 子房由3心皮合成, 花部具有吸引传粉者的特性; 花粉活力在散粉2 h后达到最大值, 柱头可授性在花朵开放后不断增强; P/O值为255.70±46.50, OCI值为3。人工套袋试验表明, 圆齿野鸦椿不存在无融合生殖, 自然条件下结实率最高, 但仅为48.76%, 自花授粉的结实率均低于人工授粉, 说明传粉者的不足导致传粉限制。综上判定圆齿野鸦椿繁育系统为兼性异交, 自交可孕, 需要传粉者进行传粉。

关键词：圆齿野鸦椿; 开花动态; 繁育系统; 花粉活力; 柱头可授性

收稿：2017-09-11   修定：2017-11-30

资助：福建省科技创新领军人才资助项目(118-KRC16006A)。

Stamen dynamics and breeding system of Euscaphis konishii Hayata

SUN Wei-Hong, YUAN Xue-Yan, WU Ling-Jiao, XIANG Shuang, ZOU Shuang-Quan^*

Fujian Colleges & Universities Engineering Research Institute of Conservation & Utilization of Natural Bioresources, Forestry College, Fujian Agriculture and Forestry University, Fuzhou 350002, China

Corresponding author: ZOU Shuang-Quan; E-mail: 282014224@qq.com

Abstract:

In order to study the flowering characteristics and breeding system of Euscaphis konishii Hayata, we observed flower characteristics, floral dynamic and pollination insects during the flowering period. We tested the pollen viability and estimated its stigma receptivity by benzidine-hydrogen peroxide. The breeding system of Euscaphis konishii was tested by the pollen-ovule ratio (P/O), the outcrossing index (OCI), and artificial pollination methods. The results showed that the population flower bloomed one time a year from mid-May to early June, and the flowering order of the cymes inflorescence of Euscaphis konishii was from top to bottom, from the inside to outside. The life span of individual flower was one day. Euscaphis konishii was a plant with bisexual flowers that were small. Each flower had 5 stamens, sometimes 4 or 6, and ovary synthesized from 3 carpels. Floral syndrome could attract pollinators. The pollen viability reached the maximum at 2 hours after anthers shedding, and stigma receptivity was increased after bloom. The value of P/O was about 255.70±46.50 and the out-crossing index was 3. The experimental results of artificial bagging show that Euscaphis konishii was apogamous and have the highest fruit setting rate, only 48.76%, and the fruit setting rate of naturally self-pollination flowers was lower than that of artificial pollination flowers, indicating the existence of pollination restriction caused by the insufficiency of pollinators. In sum, the reproductive system of Euscaphis konishii could be determined as facultative outcrossing, self-compatible and pollinators depended.

Key words: Euscaphis konishii Hayata; flowering dynamics; breeding system; pollen viability; stigma receptivity