砂梨品种花粉形态的扫描电镜研究

STUDIES ON SAND-PEAR (P. pyrifolia Nakai) POLLEN MORPHOLOGY UNDER SCANNING ELECTRON MICROSCOPE

运用扫描电镜对砂梨(P.pyrifolia Nakai)的79个品种的花粉粒形态进行观察,结果表明:1.砂梨品种花粉粒为近球形、扁球形、长球形,极面直径为22～34μm。2.花粉粒极面观多呈三角形或椭圆形,少数为近圆或方形(菱形);多数具3条萌发沟,少数有4条萌发沟。3.花粉表面雕纹(纹饰)多为条状纹,亦有网状纹、云片状纹、波浪状纹及瘤状纹,在条纹间有的无孔穴,有的有不同密度、不同大小的孔穴,条纹粗细亦存在着差别,证明品种间存在着差异。

The pollen grain forms of 79 sand-pear (P. pyrifolia Nakai) cultivars (or strains) were observed with the scanning electron microscope. It was shown: (1) The pollen grain forms of sand-pear are classified nearspheroid, oblate, prolate-spheroid. The diameters of polar plane are about 22—34 μm: (2) The polar views of most kinds of pollen grains are triangle or ellipse. Few of them are near-circle or square (diamond); Most kinds of pollen grains have three germinal apertures, few of them have four; (3) The surface sculptures of most kinds of pollen grains are striated, also reticulate, cloud veil, wave and verrucate. Some kinds of pollen grains have no foveolates, others have foveolates with different densities and diameters. Such differences may be used to identify the cultivars.