兔眼越桔(杜鹃花科)花粉形态——兼谈用极坐标测量四合体花粉的一种新方法

扫描电镜下,兔眼越桔花粉为四合体,外形为准四面体,中等大小,表面具不规则皱波状纹饰,并有多处凹陷。萌发孔沟多为3对(顶分体3条,侧分体各对应1条),以四面体几何中轴为中心,中心对称分布于四面体的3个侧面。萌发孔沟的长度、宽度、孔盖长与宽、孔盖的形状、突起的程度等,在个体间有差异,尤其是一些具有多处凹陷的花粉粒,可能是导致花粉萌发率不同的生态类型。用极坐标法描述四合体花粉的新方法可以表现其饱满度,比较传统上用极轴、赤道轴的长短表现花粉平面大小的方法,更加准确而直观。

Pollen Morphology of Vaccinium ashei J. M. Reade. (Ericaceae), with Reference to a Measurement Method of Polar Coordinate for Tetrahedral Tetrads

Pollen morphology of Vaccinium ashei was investigated by scanning electron microscopy.Most of pollen grains are tetrahedron with tetrad construction.Most of the apertures were tri-zonocol porate,distributed symmetrically at the three sides by the axis of symmetry of the tetrahedron.The pollen grains with different ecological styles of germinal apertures in length,width,length and width of lid,shape of lid and the extent of protuberances etc.,especially with several hollows could be the factors resulting in the different germination of pollen grains.The shapes and forms of tetrahedral tetrads grains may be described with a new method of polar coordinate that is more exact and more direct than with traditional measurement method of polar axis(P) and equatorial axis(E).