Abstract:

Microfilament skeleton plays important role during the process of pollen development and pollen tube growth. We observed the distribution of microfilaments in the pollen and pollen tube of Cunninghamia lanceolata by phalloidin labeling fluorescence and confocal laser scanning microscope. The images showed different distribution of microfilaments during pollen germination process. At the early stage of pollen germination, filiform microfilaments occurred in the pollen cytoplasm, and formed thick F-actin bundles around the nuclear surface; With pollen tube growth, microfilament bundles extended and distributed axially in the pollen tube; Thick F-actin bundles were absent near the pollen tube tip and a dense actin cap was formed with thin microfilament fragments in the tip of pollen tube. The microfilament density in the pollen and pollen tube was different from other angiosperms. The results sugguested that the difference in the microfilament density might be related to the slow growth of a pollen tube in C. lanceolata .

Key words: Cunninghamia lanceolata, pollen, pollen tube, microfilaments