【目的】贵州金花茶(Camellia huana)为贵州特有珍稀濒危植物,目前仅分布于册亨县双江镇附近,其自然种群处于不断衰退中。对贵州金花茶的花部特征、繁育系统及传粉生物学进行研究,揭示该物种生活史特征,并探讨影响其生殖成功的因素,为制定相应的保护和利用措施提供科学依据。【方法】以野生种群和引种栽培种群为对象,通过野外观察贵州金花茶成年植株的开花生物学、花器官特征及繁育系统、花粉活力、柱头可授性、杂交指数及授粉方式等进行研究。【结果】①贵州金花茶10—11月开花,单株花期平均20.57 d,每株单日开花20朵,平均每株开花139.71朵,种群花期约2个月。②贵州金花茶属于两性花,1~3朵成腋生或顶生,花蕾发育比较慢,蕾期平均12.47 d,单花花期为4~7 d。③贵州金花茶花冠平均直径36.85 mm,花冠平均高度31.94 mm,野生种群的花柄长、花萼宽、花柱长明显大于引种种群植株,而花药宽略小于引种种群植株。④贵州金花茶花粉在雄蕊初露期就有活力,至盛花期活力最高,之后逐渐减弱,到枯萎凋谢前还具有活力,但活力较弱。开花当天柱头即具有可授性,开花第2~3天的柱头可授性最强,柱头可授性持续期为1~2 d。雌、雄蕊生殖活力在持续时间上有相遇期,但相遇时间较短。开花时柱头和花药几乎位于同一位置,且在花朵开放的整个过程中雌、雄蕊的相对位置始终不变。⑤繁育系统检测表明,贵州金花茶花粉-胚株比(P/O)为122.11,杂交指数(I_OC)为3。套袋实验表明,贵州金花茶具有风媒和虫媒两种传粉机制,用质量分数10%蔗糖溶液点滴柱头后,再进行人工异株授粉的结实率比自然授粉高1倍,传粉昆虫为石长黄胡蜂(Dilichovespula saxonica)、墨胸胡蜂(Vespa velutina)、中华蜜蜂(Apis cerana),不存在无融合生殖,自交亲和,有时需要传粉者。【结论】贵州金花茶10—11月开花,种群花期较长,单花花期为4~7 d,属于两性花,部分雄性先熟和雌雄同位,其繁育系统为自交亲和,有时需要传粉者,为风媒和虫媒混合传粉类型。

【Objective】Camellia huana is a rare and endangered plant endemic to Guizhou province. It is only distributed near Shuangjiang Town, Ceheng County, Guizhou Province, and its natural population is in continuous decline. The floral characteristics, breeding system and pollination biology of C. huana were studied to reveal the life history characteristics of this species and explore the factors affecting its reproductive success, so as to provide scientific basis for the development of corresponding protection and utilization.【Method】In this study, the flowering biology, flower organ characteristics and breeding system, pollen viability, stigma acceptability, cross index and pollination mode of adult plants of C. huana were observed in the wild population and introduced cultivation population.【Result】(1)C. huana bloomed from October to November and average flowering time per plant is 20.57 days.Each plant blossoms 20 flowers per day, and the average flowering time per plant was 139.71 flowers. The population flowering time was about 1-2 months.(2) It is a bisexual flower and 1-3 terminal or axillary flowers. The immature bud is relatively slow, the bud period is 12.47 days on average, and the single flowering period is 4-7 days.(3) The diameter and height of the corolla were 36.85 and 31.94 mm, respectively. The stalk length, calyx width and style length of the wild population were significantly longer than those of the introduced population, while the anther width was slightly smaller than that of the introduced population. (4) The pollen vitality begins at the early stamen showing stage,and they achieve their maximum vitality after the petals have unfolded, and then gradually weakened. Before withering, it still had vitality, but the vitality was weak.The stigma receptivity started from bloom and lasted for one to two days,and the pollen viability was high in the whole florescence.Male and female reproductive units in the duration of the encounter period,but the time is short. The stigma and anther are almost in the same position at the time of flowering,and the relative position of the stamen and style remained unchanged in the whole flowering process.(5)A study of the breeding system indicated that the pollen-ovule ratio was about 122.11,and the crossing index was three.The bagging experiments showed that C. huana was adapted to both wind and insect pollination,After dropping stigma with 10% (mass fraction) sucrose solution, the seed set rate of artificial cross-pollination was twice higher than that of natural pollination.The pollination insects were Dilichovespula saxonica, Vespa velutina and Apis cerana.In the breeding system of this species,out-crossing predominates, although partially self-compatible,it requires pollinators.【Conclusion】C. huana blooms in October to November, the population flowering period is relatively long, the single flower flowering period is 4-7 days, belongs to the bisexual flowers, some males premature and male and female, its breeding system is self-compatible, sometimes need pollinators, anemophilic and entomophilic mixed pollination type.