Preliminary studies on mustard taxonomy based on pollen morphology
芥菜花粉形态特征及分类初探

Pollen grains of 17 mustard subspecies were examined under scanning electron microscope. The result showed that the pollen shapes were nearly spherical, or spheroidal, or super-spheroidal from the equatorial view, depending on cultivars of mustard. The size of pollen grain showed great variation among subspecies, but it was rather difficult to classify the subspecies according to the pollen grain size. However, by comparison of the sculpture of pollen extine and germinal pore, as well as pollen shapes and pollen size, mustard subspecies used in this experiment could be classified. This classification was comparable to the traditional subspecies classification.