白菜细胞核雄性不育花药的细胞化学观察

THE CYTOCHEMICAL OBSERVATION OF ANTHERS OF CHINESE CABBAGE'S MALE-STERILE

对一种由一对隐性基因控制的白菜细胞核雄性不育和可育株的花药进行了细胞学和组织化学研究。种子播种后,有1/4植株为不育株,其余的为可育株。通过对不育株和可育株花药发育的细胞学观察,确认不育花粉的败育发生在小孢子发育时期。用组织化学的方法研究了可育株和不育株花药发育过程中的多糖和脂类的分布动态,发现在减数分裂前,可育花药和不育花药的药隔细胞中都储藏了大量的淀粉粒。二者的差异仅是不育花药的绒毡层细胞液泡化明显。在减数分裂后的小孢子发育时期,可育花药的绒毡层细胞具有将药隔细胞中的淀粉粒多糖吸收并转化成脂类的功能,小孢子及以后的二胞花粉中也积累了大量的脂类储藏物质在不育花药中,虽然减数分裂后药隔细胞中的淀粉粒也都消失,但绒毡层细胞中的脂类物质相比很少,同时绒毡层细胞显示了明显的多糖反应,表明不育花药的绒毡层细胞将糖类转化为脂类的功能受阻。在小孢子的表面有些脂类物质,但在细胞质中却没有脂类积累。这一结果暗示在该种白菜细胞核雄性不育株中,由于花药绒毡层细胞转换多糖为脂类的功能失常,导致了小孢子的败育。

A Chinese cabbage (Brassica campestris L.ssp.chinensis Makino) produces 1/4male sterile and 3/4 fertility in offspring.The sterile plant can be identified from the color ofcorolla that is some white when it grows out.The fertile and sterile anthers were researched us-ing cytological and cytochemical methods.Thick sections of both anthers of different developmen-tal stages were stained with Toluidine blue for general cytological observation and stained withthe 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 bothfertile and sterile anthers stored a lot of starch grains.Neither starches nor lipid drops were intapetal trod microspore mother cells.The only difference of both anthers was that the tapetal cellsof sterile anthers contained more vacuoles than those of fertile anthers.After meiosis of mi-crospore mother cells,the starch grains in connective tissue of fertile anthers disappeared,thetapetal cells synthesized abundant lipid drops,and the microspores also began to accumulate lipiddrops.In sterile anthers,the starch grains in connective tissue also disappeared,but only a fewlipid drops appeared in tapetal cells.The tapetal cells,however,became red,suggesting the cellcontained 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 fertileanthers at the same developmental stage.This resuh suggested that in the cabbage,the starchgrains in connective tissue were transformed into polysaccharide and transported to tapetal cells,then these cells transformed polysaccharide into lipid material that was absorbed by developingmicrospore.In sterile anthers,however,polysaccharide in the tapetal cells could not be trans-formed to lipid.The functional default of tapetal cells duriug lipid metabolism led to microsporeabortion.This is new sample in which the functioual default of tapetal cells will make pollenabort,and will enhance research field in male sterile in higher plants.