四川黄龙沟少花鹤顶兰繁殖成功特征  

Pollination success of Phaius delavayi in Huanglong Valley,Sichuan

作　　者：黄宝强[1] 寇勇[2] 安德军[2] 

机构地区：[1]南昌工程学院,南昌330099 [2]四川省黄龙国家级风景名胜区管理局,黄龙624000

出　　处：《生态学报》2012年第21期6795-6802,共8页Acta Ecologica Sinica

基　　金：国家自然科学基金项目(30770379);中国科学院重大创新项目(kzcx2-yw-414)

摘　　要：少花鹤顶兰(Phaiu delavayi)是多年生、多次结实的具有克隆能力的地生兰科植物,是中国特有种。目前少花鹤顶兰开花物候、花寿命、繁殖成功等生物学特征尚不清楚,而这些资料是开展少花鹤顶兰进化和保护生物学研究的基础。利用2005—2007年四川黄龙沟少花鹤顶兰的调查数据,对少花鹤顶兰繁殖成功特征进行了研究。结果表明黄龙沟少花鹤顶兰每个花序的平均花朵数为3(1—7)朵。叶和花的形态指标在年季间无显著变异。2005—2007年3年间的开花物候没有明显的差异,花期始于6月中旬,于7月底至8月初结束,持续约6—7周,80%—90%的花在7月初的开花高峰期开放,属花集中开放模式。花寿命与是否授粉密切相关,成功授粉的花寿命比没有授粉的花寿命短。少花鹤顶兰是自交亲和的,但其结实完全依赖于两种熊蜂的传粉,不存在自动自花授粉和无融合生殖现象。柱头可授性和花粉活力可维持15 d左右。繁殖成功率年季间的变化很大,并表现出逐年下降的趋势,花粉移走率为18%—51%,自然结实率为10%—36%。繁殖成功下降的趋势可能与黄龙沟喷洒农药有关。Phaius delavayi is a long-lived, polycarpic, pseudobulbous clonal orchid species and is endemic to China. Generally, the flower phenology, flower life span, and pollination success are important features for plant species evolution and conservation. Those features in Phaius delavayi were studied detailed in 2005--2007 in Huanglong Valley, Sichuan. The results showed that the plants have 3 or 4 leaves, and the largest leaf were 16.9--17.5 cm long, 4.8 --4.9 cm wide. The inflorescence is sparsely 1--7-flowered （ with mean 3 ） , exceeding height of leaves, 18.4--19.5 cm. Flowers widely opening, with 1.9--2. 2 cm long, 1.1 cm wide labellum, and 1.0--1.2 cm long spur. Length of the leaf and floral traits were not significant different, as well as flower phenology during three years. Fruits were 20.78 mm long, 8.10 mm wide, and 00424 g weight. The inflorescence growth began in mid May and last about 50 days, continued until early July. Flowering began in mid June and last about 6--7 weeks, continued until late July/early August, with 80%--90% flowers flowered in a peak time （last about 10 days） in early July. Life span of inflorescences showed considerable variation among years, which were 23, 21, and 29 days for 2005, 2006, and 2007, respectively. The flower life span was closely correlated with pollination, that with successful pollination was 15--19 days, significantly shorter than that of flowers without pollination （17--22 days）. Fruit maturity was in mid-latter September, and the leaves were yellow and withered. The results of pollinia viability and stigma receptivity experiments showed that the flowers are self-compatible, but the reproductive success is strictly dependent on visitation by pollinia vectors （ Bombus hypnorum and B. lepidus）, and there is no autogamy and apogamy in this speices. The stigma has receptivity at the first day of flowering, and can last about 15 days, and lost receptivity completely 20 days after flowering. The fruit set was higher 1--10 days after flowering than th

关 键 词：少花鹤顶兰 开花物候 花粉移走率 结实率 繁育系统 保护 

分 类 号：Q945[生物学—植物学]