牛至生殖生物学特性研究

Study on Reproductive Biology of Origanum vulgare L.ssp.viride(Boissier)Hayek

目的:研究牛至亚种Origanum vulgare L.ssp.viride(Boissier)Hayek的生殖生物学特性,为其良种选育等提供理论依据。方法:观察记录开花物候及形态特征,用TTC法检测花粉活力,联苯胺-过氧化氢法检测柱头可授性,估算杂交指数(OCI)并计算花粉胚珠比(P/O),通过6种人工授粉处理确定繁育系统类型。结果:花期为4~8月,单花花期6~8 d。开花后其花粉活力高、持续时间长,柱头在裂片张开后才具有可授性,持续至花朵衰败。其OCI值为4,据Dafni标准其繁育系统为部分自交亲和异交,需要传粉者;P/O为2454.00±50.85,据Cruden标准为兼性或专性异交。授粉试验结果显示:套袋未授粉的不能结实,自交、异交均能结实。观察到蚂蚁、蝇类昆虫访花。结论:O.vulgare ssp.viride的繁育系统为兼性异交,部分自交亲和,需要传粉者。

Objective:The reproductive biology of Chinese herbal medicine Origanum vulgare L.ssp.viride(Boissier)Hayek was investigated to provide a theoretical basis for improved varirety breeding.Methods:Floral morphology and flowering characteristics were carefully observed and recorded.Pollen viability was tested by 2,3,5-triphenyltetrazolium chloride(TTC)solution,and stigma receptivity was tested through benzidine-hydrogen peroxide method.To determine the breeding system,the outcrossing index(OCI)was estimated,pollen/ovule(P/O)ratios were calculated,and controlled pollinations were conducted.Results:O.vulgare ssp.viride bloomed from April to August.Anthesis began in the morning and lasted for about 6-8 days.Pollen viability and stigma receptivity remained high throughout the flowering process.The OCI was 4,so the breeding system was“partly self-compatible and xenogamy,needing pollinator”according to Dafni’s standard.The P/O ratio(2454.00±50.85)indicated facultative or obligate xenogamy according to Cruden’s standard.No fruit set occurred in unpollinated bagged plants.Flowers under self-pollination and cross-pollination both could bear fruits.Some ants and flies were found as flower visitors.Conclusions:The breeding system of O.vulgare ssp viride is“facultative xenogamy and partly self-compatible,needing pollinator”.