新型陆地棉细胞质雄性不育系花器形态学和细胞学观察

 采用石蜡切片法，对一种来源于陆地棉的新型细胞质雄性不育材料的3份转育材料（G22A，H109A和1793A）的花药发育过程进行了花器形态及细胞学观察。花器形态和细胞学观察结果表明，G22A，H109A和1793A三个不育系均花瓣小，花丝短，柱头明显外露，败育彻底，无花粉。败育时期主要发生在造孢细胞增殖时期至小孢子母细胞减数分裂前，表明这3份不育材料不育性状不受细胞核基因的影响。对不育材料与其保持系细胞学观察发现，不育材料与正常花药发育细胞学形态上主要差别是绒毡层发育。不育系绒毡层的着色不明显，大小与中层细胞相似且在整个花药发育过程中不降解，而保持系绒毡层的着色深，在小孢子发育过程中逐渐降解。因此，根据细胞学研究结果可以说明花药中绒毡层发育异常是该来源于陆地棉的新型细胞质雄性不育材料败育的细胞学基础。

Studies on the Morphological and Anatomic Characters of a Novel CMS in Gossypium hirsutum L.

Morphological and anatomic characters of the flowers and anthers in a new kind of cytoplasmic male sterile (CMS) of three accessions, named G22A, H109A, and 1793A, were studied in this paper. As the results shown that all the three new CMS accessions were completely male sterile, their flowers were the characters of smaller petals, shorter filaments, and no pollens, without any difference among them. The anatomical and cytological observation showed that the abortion of auxocyte cells in the three CMS lines took place between the sporogneous cell division to the beginning of PMC meiosis. The most significant difference in anatomical and cytological characters between the new CMS lines and their fertile genetic background lines, named G22B, H109B, and 1973B, was the development of the tapetum cells. Comparing with the tapetal cells of the fertile lines, those of the sterile anthers were much smaller with lightly stained after dyeing. The size of those cells was almost as big as that of middle layer cells. There was no abortion process for the CMS tapetum cells during the anther development, while those of their fertile genetic background lines were darkly stained, bigger in size, and degenerated gradually during the anther development, which was important for the development of anther to produce fertile pollens. So the abnormal development of tapetum cells was probably the reason led to the sterility of pollens for the new CMS lines.