Abstract:

With the help of methods of thin-section and histochemistry dynamic changes of resin droplets and starch grains in resin duct cells at different developmental stages of resin duct are observed and studied.At the initial stage, few resin dropletS and 2-5 starch grains occur in the cytoplasm, at formative stage, the number of resin droplets gradually increasee.their volumeenlarges, starch grains changes with a same trend, both of them all are evenly distributed in the cytoplasm.At the mature stage, the number of resin dro plets obviously decreases, most of them occur in the cytoplasm near lumen, no great change take places in the number of starch grains, but their volume apparently contracts, usually they are present in the cytoplasm far away from lumps. During the development of resin duct, no, obvious change appears in the number and volume of resin droplets and starch grains in sheath cells.

Key words: Pinus tabulaeformis Carr., Resin duct, Resin droplet, Starch grain