摘要：The morphological characteristics of the pollen grains from the Pitaya germplasms and the genetic relationship of the germplasms were analyzed through experiments, to provide the palyno- logical basis for the systematic classification and identification of the Pitaya germplasms. The pollen morphology of 16 germplasms from 9 areas of Fujian Province was observed by JSM-6380LV scanning electron microscope after fixed, cleaned, dehydrated step by step, dried, and coated with gold. The ultrastructural characteristics of pollen grain population (enlarged by 200 times), pollen grain individuals (1300 times larger) and outer wall ornaments in the middle of the equatorial surface of the pollen grains (3000 times magnified) were observed and taken photomicrograph from the representative field of vision. The comprehensive data obtained by the experiment were statistically analyzed by the DPS data processing system (Duncan new repolarization difference method) and SPSS19.0 software was used for analysis of a clustering component, which is based on the sum of squares of deviations, and a tree of 16 taxonomic units was made. The results showed that the pollen grains were nearly spherical (0.92
