国产山龙眼科花粉形态及外壁超微结构的研究

POLLEN MORPHOLOGY AND WALL ULTRASTRUCTURE OF PROTEACEAE IN CHINA

This paper examined pollen grains of Helicia Lour., Heliciopsis Sleum. and Grevillea R. Br. with LM, SEM and TEM. The result showed that the exine sculpture and the thickness of various wall layers of Heliciopsis , on the one hand, are different from these of Helicia, the former with reticulate sculpture and thicker wall layers(tectum 0.5-0.7um, columellae 0.8-1um, foot layer 1-1.5um, the total exine 2.5-3um), the latter with scabrate-granulate sculpture and thinner wall layers(tectum 0.3-0.4um, columellae 0.15-0.2um, foot layer 0.5-0.6um, the total exine only 1-1.2um), and on the other hand are similar to those of Sphalmium and Carnarvonia, both of which also have reticulate sculpture and thicker wall layers. Palynology supports Sleumer's view to separate Heliciopsia from Helicia. Heliciopsis, Sphalmium and Carnarvonia are remotely related in Johnson's system, but because of their similarity of pollen morphology including exine sculpyure and the thickness of various wall layers, it seems necessary to reconsider their phylogenetic relationships by further study of other related genera, especially those ofGrevilleoideae of Proteaceaeand at the same time incorporation other data on various subjects.