连翘的二型花柱

报道了连翘中的二型花柱(长花柱和短花柱)。长花柱的柱头和雄蕊高度分别为6.12±0.05 mm和2.35±0.04mm,短花柱则为2.23±0.04mm和6.02±0.06mm。短花柱花的花冠大小明显超过长花柱。开放授粉条件下,长短花柱花的座果率分别为9.11 %±0.04%和8.93 %±0.07%。人工异交的座果率在长-短(36.8%±0.04%)与短-长(36.2%±0.07%)组合间无明显差异(F(1,39)=1 .38,P=0.14)。人工异交实验表明,传粉者限制可能发生在生长于中国东北部的人工连翘种群中,这可能是因为该地区早春的低温和多风气候条件影响传粉者的种类和活动。

Distyly in Forsythia suspensa (Oleaceae)

Distyly provides precise pollen transfer without the costs that are associated with sexual interference and self-pollination. In thirty populations of distylous Forsythia suspensa,style-morph ratios varied from isoplethy (1.00 long-morph:1.00 short-morph,n=17 populations) to L-biased (1.14 long-morph:1.00 short-morph,n=13 populations). Under open pollination condition,there was no significant difference in fruit set between long-(9.11%±0 01%) and short-(8.93%±0.06%) styled morphs (F(1,39)=2.47,P=0.25). The lower fertilizations of controlled intramorph pollinations (2.71%±0.02% in long-long and 2 58%±0.01% in short-short combinations) indicated that F.suspensa is intramorph-incompatible. There was no significant difference in fruit set of cross-pollination between long-short-(36.41%±0.07%) and short-long-(36.27 %±0.03 %) styled morphs combinations (F(1,39)=1 38,P=0.14). The results of artificial outcrossing indicated that pollinator limitation may occur in the artificial populations of F.suspensa in northeast of China,this may be because that the low temperature and much windy in the early spring influence pollinators' kinds and activities.