番茄花药发育中多糖和脂滴的分布特征

The Distribution Features of Polysaccharide and Lipid Drops in the Development of Tomato Anther

花药发育中的营养物质转运和转化规律很复杂。采用组织化学方法对番茄花药发育中的多糖和脂滴分布特征进行了分析。结果显示:造孢细胞时期仅花药药隔细胞中有较多淀粉分布。小孢子母细胞的胼胝质壁呈现明显多糖特征,药隔细胞中的淀粉减少。减数分裂后四分体时期的花药中营养物质没有明显变化。在游离小孢子发育早期,药隔细胞中淀粉数量又增多;游离小孢子的花粉壁局部呈现多糖特征。到小孢子发育晚期,液泡化小孢子中既没有淀粉也没有脂滴,仅在花粉壁部位仍显示了多糖特征;药隔细胞中的淀粉数量明显减少,此时绒毡层细胞变形、退化。小孢子分裂后,二胞花粉中先出现一些脂滴。伴随着花粉的发育成熟,又出现了大量的淀粉。开花时花药表皮细胞中也聚集了较多的脂滴。番茄花粉中先积累脂滴、后积累淀粉、以及成熟花粉中积累大量淀粉和脂滴的现象是其花粉发育中营养物质代谢的特征,呈现出不同植物的特异性。

The transportation and transformation of nutrient material occurring in developing anthers is not clear. The distribution features of polysaccharide and lipid in developing anthers of tomato were analyzed using histochemical method. Some starches appeared in connected somatic tissue of anther during the sporogenous cell stage. Before the meiosis of microspore mother cell,a thick polysaccharide callose wall was formed accompanying starch reduction in connected tissue. After meiosis,polysaccharide material in anther did not change in tetrad stage. After microspores were released from tetrad,the starches again increased in the connected cells,and polysaccharide material appears in the partial intine of pollen. At the late microspore stage,the microspore formed a large vacuole and contained neither lipid drop nor the starch,and only pollen wall displayed red polysaccharide. The amount of starches in connected somatic cells decreased. The tapetal cells changed form and degenerated. After microspore division,quite amount of lipids first appeared in bicellular pollen and then many starches following pollen development. With anther maturity,many lipids and some starches accumulated in epidermal cells. It is a characteristic of nutrient metabolism of tomato pollen that pollen first accumulated lipids and then starches,as well as mature pollen accumulated many starches and lipids simultaneously. The characteristic of nutrient metabolism in tomato pollen also displays species-specific in plants.