42个三角梅品种的花粉形态比较分析

采用扫描电镜对三角梅42个品种的花粉形态作观察,参考已发表的三角梅花粉育性的数据,探究花粉形态和花粉育性的联系。采集42个三角梅品种的花粉,人工干燥后进行电镜形态观察,采集3000倍下的近极面观、远极面观、赤道面观、侧面观以及10000倍下的外壁网脊等图片,确定三角梅不同品种花粉的整体外观形态。测定花粉的大小、萌发沟数量,对比不同品种和不同花粉部位的芽突数量。三角梅花粉呈现单侧凹陷、单侧突出的凸饼状结构,三角梅不同品种的花粉粒直径在21.64~31.14 μm之间。少数品种的萌发沟有3个,萌发沟少于3个的品种主要集中于花粉育性低的品种中。花粉表面网脊状褶皱,褶皱上芽突数量不等,不同品种有所差别。芽突数量与植株花粉育性关系密切,花粉育性高的品种花粉表面芽突数量多于花粉育性低的品种。花粉粒表面芽突数量减少,降低三角梅花粉的附着能力,这有可能是导致该品种花粉育性极低的原因之一。

Study on the Pollen Morphology of 42 Varieties of Bougainvillea

The pollen grain morphology of 42 varieties of Bougainvillea was observed by using electron microscopy. Compared with the published data of the pollen sterility of Bougainvillea, the relationship between pollen grain morphology and pollen sterility was studied. We collected the pollen of the 42 cultivated species of Bougainvillea and carried out the drying and morphological observation. Pictures of pollen distal view, pollen proximal view and pollen equatorial view under 3000 times and the outer wall of the network under the 10000 times were gathered, to determine the pollen grain morphology of the 42 varieties of Bougainvillea. The size of pollen and the number of germination ditches were measured. The number of buds of different varieties of Bougainvillea and different areas of pollen were compared. It was found that the appearance morphology of Bougainvillea was convex cake structure which was unilateral depression and unilateral protruding. The pollen grains of different varieties of Bougainvillea were 21.64-31.14 μm. There were three germination ditches in a few varieties and most of the varieties had less than three germination ditches. There were a lot of reticulate folds on the surface. The number of buds on the folds was different in different varieties and the number of buds was closely related to the pollen sterility. The number of pollen surface buds of varieties with high pollen sterility was higher than that with low pollen sterility. The low number of pollen surface buds in hybrid varieties could reduce the attachment ability of pollen and cause low pollen sterility.