2种鹅掌楸的开花习性与传粉媒介

Blooming characteristics and pollinators of Liriodendron chinense and L.tulipifera

在包含中国鹅掌楸Liriodendron chinense和北美鹅掌楸L.tulipifera17个种源的试验林内,选取6个搭架的个体,连续2 a定点观察了鹅掌楸的开花习性和传粉媒介。结果表明,鹅掌楸不同种源始花期有差异,但同一种源不同个体的始花期大致相同;而盛花期的开花数量在不同种、种源和个体之间均存在差异。鹅掌楸为虫媒传粉,但传粉媒介种类与访花频率在种间大致相同。试验观察到访花动物共14种,分别来自于双翅目Diptera,膜翅目Hymenoptera,鞘翅目Coleoptera,鳞翅目Leoidoptera,蜘蛛目Araneae,其中,食蚜蝇科Syrphidae 1种,西方蜜蜂Apis mellifera,蚁科Formicidae 2种等4种昆虫为鹅掌楸主要访花昆虫。不同种类昆虫其访花行为各有特点。昆虫访花频率与植株日开花量之间存在相关性,大致趋势是随着日开花量的增多昆虫访花频率增大。

Blooming characteristics and pollinators of Liriodendron chinense（Chinese tulip tree） and L.tulipifera（tulip tree）in a provenance trial plantation including 17 provenances were investigated based on observations over two years on 6 trees in Jurong City,Jiangsu Province.Results showed a moderate difference for initial anthesis among 6 provenances,but no difference among individuals within a provenance.For the number of flowers during bloom,variations were also found among species,provenances and individuals. However,no interspecies variations were found for the pollinators and their visiting frequency.Altogether,14 animal species from the orders Diptera（2）,Hymenoptera（6）,Coleoptera（4）,Leoidoptera（1）,and Araneae（1） were observed visiting the flowers of Liriodendron.Of these orders three families, namely Syrphidae（flies）（1）and Formicidae（ants）（2）,as well as one species,Apis mellifera（bees）,were major visitors.When visiting flowers,different visitors had different behaviors with geitonogamy being observed.Generally,the visiting frequency of the visitors was related to the number of daily flowers blossom,the greater the number of blossoms,the higher the visiting frequency.