北陵鸢尾的传粉生物学研究

The Pollination Biology of Iris typhifolia

本研究采用定点观察和人工授粉的方法,以北陵鸢尾(Iris typhifolia)为试验材料,对其开花物候、花部形态特征及繁育系统等方面进行深入研究,揭示了北陵鸢尾的传粉机制,为其繁殖应用及保育工作提供理论基础。北陵鸢尾5月中旬进入现蕾期,5月末进入始花期,6月初进入盛花期,6月末进入末花期。单花花期3~4 d,单株花期12~16 d。花药外向开裂,紧贴花柱分支外侧,雌雄异位,在花朵开放过程中花药、柱头相对位置不变;雄蕊先熟,在开花当天,花粉活力及柱头可授性最强;杂交指数为4,花粉胚珠比为322.15,有性繁育系统为自交亲和,异交,需要传粉者,不存在无融合生殖现象,主要访花昆虫有西方蜜蜂(Apis mellifera)、东方蜜蜂(A.cerana)、切叶蜂属(Megachile sp.)、黑带食蚜蝇(Episyrphus balteatus)和大灰优食蚜蝇(Syrphus corollae)。

In this study,we used the Iris typhifolia as the test material to conduct in-depth research on its flowering phenology,morphological characteristics of the flowers and breeding system by means of fixed-point observation and artificial pollination.It will reveal the pollination mechanism of I.typhifolia and provide a theoretical basis for its breeding application and conservation.The results showed that I.typhifolia entered the present bud stage in mid-May,the beginning flower stage in late May,the full flower stage in early June,and the final flower stage in late June.The flowering period of single flower was 3~4 d,and the flowering period of single plant was 12~16 d.The anthers dehisced outwardly,close to the outer side of the stylar branches,and the male and female were heterozygous,and the relative positions of the anthers and stigma remained unchanged during the process of flower opening;the stamens ripened first,and on the day of flower opening,pollen vigour stigma pollination was the strongest;the outcrossing index(OCI)was 4,the pollen/ovules ratio was 322.15,and the sexual reproduction systems were autogamous and heterozygous,which needed pollinators without the phenomenon of apomictic reproduction.The main flower-visiting insects were Apis mellifera,A.cerana,Megachile sp.,Episyrphus balteatus and Syrphus corollae.