扁穗牛鞭草几个有性生殖特性的研究

Some Reproductive Characteristics of Hemarthria Compressa

以牛鞭草“广益”、“重高”两个品种为材料 ,对抽穗开花的形态学、花粉活力和结实率进行了研究。结果表明 :扁穗牛鞭草于 7月下旬至 8月上旬抽穗 ,每花序需 9d完成抽穗。开花集中在每天下午 5～ 7点 ,开花顺序为自上而下。每小花开花全过程 47～ 86min。“广益”和“重高”群体平均花粉粒活力分别为 2 4 0 %和 16 2 % ;同一花序顶端小花花粉粒活力较高 ,最高分别为 78 4%和 6 8 6 % ,自上而下分别于第 8小花和第 10小花以下的花粉粒全部无活力 ,一个花序花粉粒平均活力分别为 2 2 1%和 15 2 %。“广益”和“重高”牛鞭草的套袋结实率分别为 6 4%和4 2 % ,自然传粉结实率分别为 7 8%和 6 6 %

The heading and inflorescencing morphology, pollen viability and seed bearing rate of two Limpograss cultivars were studi. Results show that Limpograss heads from the end of July to the first ten days of August, with heading lasting for 9 days of one inflorescence. Limpograss florets open only from 5 pm. to 7 pm., from top to bottom. One floret blooms in 47～86 minutes. The average population pollen viability (PV) of limpograss two cultivars are 24 0% and 16 2% respectively. The top floret PVs of same inflorescence are higher than those of bottom florets, with PVs of cv.the highest. Guangyica reachs 78 4% and cv. Chongqinalta 68 6%, and the PVs of No.8 floret or No.9 floret and those beneath them are zero. The seed bearing rates of limpograss cv.Guangyica and cv.Chongqinalta are 6 4% and 4 2% in sack pollination, 7 8% and 6 6% in open pollination.