红丁香的花部特征与繁育系统

通过对红丁香的花部特征观测、花粉形态扫描、花粉-胚珠比测定、柱头可授性测定、杂交指数判定及人工授粉实验,研究了红丁香的花部综合特征与繁育系统类型。结果表明:红丁香花期为5月底至6月初,单花花期5～6d;单花干柱头缩入式雌雄异位,长椭圆形、网脊光滑。雄蕊2～3枚,贴壁生长,花粉三孔沟;红丁香的花粉活力在开花第1天最高,之后逐渐降低,第5天活力丧失;柱头可授性先上升后下降,第4天达到顶峰;杂交指数(OCI)为4,P/O值为9 500,结合人工授粉实验认为,红丁香自交授粉部分亲和,异株授粉座果率高,其繁育系统属兼性自交,以异交为主,需要以昆虫作为传粉媒介。估算发现,红丁香单花序潜在的种子产量为8.6g,而实际花序的种子产量为2.3g左右,只占潜在种子产量的26.3%,具有巨大的提高产量空间。

Floral Characteristics and Breeding Systems of Syringa villosa

We did research on flower feature and breeding system of Syringa villosa by studying flower feature,pollen morphology,pollen-ovule ratio,stigma receptivity,hybrid index and artificial pollination.The results showed that S.villosa blooms from late May to early June,and single flower blossom generally lasts for 5 to 6 d.2 or 3 stamens grew on the upper part of the corolla tube,while the long oval dry pistil grows at the bottom of corolla tube which has smooth mesh.The pollen was tricolporate and the pollen vitality decrease along with the day then finally lose viability at the fifth day.The stigma receptivity enhance first and then weaken.The highest receptivity was observed at the fourth day.Its outcross index(OCI)was 4 and pollen-ovule ratio(P/O)was 9500.Combined with artificial pollination experiments,it is believed that the self-pollination of Syringa villosa is partially affinity,and the fertile fruit rate of heterologous pollination is high.The breeding system of Syringa villosa was facultative self-intersection which mainly relys on outcross needing insects as pollinator.It was estimated that the potential seed yield of single flower inflorescence was 8.6 g while the actual was about 2.3 g,which accounts for only 26.3%.So it has huge room to increase yield.