5个薄壳山核桃品种花粉形态电镜扫描观察

为了详细描述薄壳山核桃花粉的形态特征,从而为其品种的分类鉴定及系统演化关系的研究提供理论依据,利用电镜扫描技术,对‘Western’、‘Caddo’、‘Sauber’、‘Stuart’、‘Mahan’这5个薄壳山核桃品种的花粉形态进行了观察与分析。结果表明:5个薄壳山核桃品种花粉的外部形态为近球形或扁球形,其极面观为近三角形或近圆形,赤面观均为椭圆形;‘Sauber’的花粉体积最大,‘Western’的花粉体积最小;5个品种的花粉均有3个萌发孔,均匀竖排在赤道上;‘Western’、‘Sauber’、‘Stuart’和‘Mahan’的花粉表面纹饰较相似,均呈瘤状纹饰,而‘Caddo’为网状纹饰。文中根据花粉表面纹饰及花粉体积大小的演化规律判定,5个品种中,‘Caddo’和‘Western’为较进化的品种,‘Sauber’则为较原始的品种。

Observation of pollen morphologies in ifve cultivars of Carya illinoensis by SEM

This study was aimed at describing the morphological characteristics ofCarya illinoensis pollen in detail, so as to provide some theoretical basis for studies about classiifcation, identiifcation and phylogenetic relationships of the cultivars. Pollen morphologies of ifve cultivars ofC. illinoensis,‘Western’, ‘Caddo’, ‘Sauber’, ‘Stuart’ and ‘Mahan’, were observed by scanning electron microscope (SEM). The results showed that the pollens in 5 cultivars were nearly spherical or close flat globose. The polarview was nearly triangle or nearly round, and the side view was oval. The volume of ‘Sauber’ pollen was the biggest, and the smallest was the volume of ‘Western’ pollen. All of the ifve cultivars’ pollens had three germinalapertures and evenly vertical rowed in the equators. The ornamentations on the surfaces of‘Western’, ‘Sauber’, ‘Stuart’ and ‘Mahan’ pollens were similar and showed nodular ornamentation, while ‘Caddo’ pollen had reticulate ornamentation. According to the evolutionlaw in surface ornamentation and volume of pollens, it was determined that ‘Caddo’ and ‘Western’ were more evolved and ‘Sauber’ was more primitive.