通过野外调查和定点观测、采用人工授粉以及扫描电镜观察方法,对分布于浙江西天目山的中国特有兰科(Orchidaceae)植物无距虾脊兰(Calanthe tsoongiana Tang et F. T. Wang)野生植株的生长特性及花部形态特征进行了研究。结果表明:无距虾脊兰分布于西天目山海拔470 ~550 m 处,在腐殖质丰富、湿度较大且排水良好、有岩石裸露的地带生长良好,并能耐0 益以下的低温。其生长发育过程可分为萌芽期、开花期、果期及衰亡期4 个时期。每个基株可有多个分株,但实生苗数量不足50%;该种具有有性和无性2种繁殖方式,但以无性繁殖为主。该种为总状花序,由15 ~39 朵花聚集而成,每朵花由3萼片、2花瓣、1唇瓣和1 蕊柱构成,其中萼片略长于花瓣,二者均为紫褐色带淡绿色脉纹;唇瓣黄色并有紫色斑点;紫色花药内含有8 个近卵形的花粉块。花期3 月份至4 月份,持续时间约19 d,单花开放时间平均为8. 14 d。自然状态下结果植株数量较少,一般每个花葶上有1 ~4 个果实。开花后前3 天实施人工自花授粉或人工异花授粉,无距虾脊兰的结果率均可达100%,表明该种的交配系统为自交和杂交混合系统,自交和异交能力均较高。

Through field survey and fixed-p oint observation and by means of artificial pollination and scanning electron microscopy observation, growth characteristics and floral morphological feature of wild individual of Chinese endemic species Calanthe tsoongiana Tang et F. T. Wang distributing in Xitianmu Mountain of Zhejiang Province were researched. The results shows that C. tsoongiana distributes in altitude 470-550 m of Xitianmu Mountain, and grows well in rock exposed zone with humus-rich, high humidity and better drainage and can resist to low temperature below 0 ℃. Its growth and development process can be divided into four stages including budding, flowering, fruiting and decline stages. Each genet can germinate several ramets, but the percentage of number of seedlings from seeds is below 50%. The species possesses both sexual and asexual reproduction modes, in which asexual reproduction plays predominant role. The species possesses raceme composed of 15-39 flowers, and each flower consists oaf three calyxes, two petals, one labellum and one gynostemium. In which, calyx is slightly longer than petal and both of them are purple-brown with light green veining; labellum is yellow with purple dots; purple anther contains eight subovate pollinia. Flowering stage of the species is from March to April with a duration time of about 19 d, and average opening time per flower is 8. 14 d. Fruiting plant number is less under wild condition, and generally, only with 1 -4 fruits of each scape. When artificial self- pollination or artificial cross-pollination are done in the first three days after flowering, its fruiting rate can achieve 100%, meaning that its mating system is a mixture of selfing and cross mating system with highly selfing and cross mating ability.