[The cytochemical observation of anthers of Chinese cabbage's male-sterile].

ABSTRACT

A Chinese cabbage (Brassica campestris L. ssp. chinensis Makino) produces 1/4 male sterile and 3/4 fertility in offspring. The sterile plant can be identified from the color of corolla that is some white when it grows out. The fertile and sterile anthers were researched using cytological and cytochemical methods. Thick sections of both anthers of different developmental stages were stained with Toluidine blue for general cytological observation and stained with the periodic-acid-Schiff's (PAS) technique to detect polysaccharides (red), with Sudan black B (SBB) to detect lipids (black). Before meiosis of microspore mother cells, connective tissue of both fertile and sterile anthers stored a lot of starch grains. Neither starches nor lipid drops were in tapetal and microspore mother cells. The only difference of both anthers was that the tapetal cells of sterile anthers contained more vacuoles than those of fertile anthers. After meiosis of microspore mother cells, the starch grains in connective tissue of fertile anthers disappeared, the tapetal cells synthesized abundant lipid drops, and the microspores also began to accumulate lipid drops. In sterile anthers, the starch grains in connective tissue also disappeared, but only a few lipid drops appeared in tapetal cells. The tapetal cells, however, became red, suggesting the cell contained some polysaccharide material. Pollen abortion in sterile anthers occurred in this stage. The aborting microspores accumulated very less lipid drops in its cytoplasm than those in fertile the starch This result suggested that in the cabbage, the starch grains in connective tissue were transformed into polysaccharide and transported to tapetal cells, then these cells transformed polysaccharide into lipid material that was absorbed by developing microspore. In sterile anthers, however, polysaccharide in the tapetal cells could not be transformed to lipid. The functional default of tapetal cells during lipid metabolism led to microspore abortion. This is new sample in which the functional default of tapetal cells will make pollen abort, and will enhance research field in male sterile in higher plants.