两个萝卜雄性不育材料胞质的细胞学与分子鉴定

Cytological and Molecular Identification of Cytoplasm in Two Male Sterile Lines in Radish

本研究以晚抽薹萝卜雄性不育系及其相应保持系为试材,石蜡切片法显微观察小孢子发生的细胞学结果表明:不育系NAURWA01、NAURWA13败育方式相似,在四分体之前的小孢子与保持系没有明显差别;单核小孢子早期绒毡层出现小液泡,逐渐汇集成大液泡,外粉壁变薄,绒毡层径向伸长异常膨大,挤压小孢子,细胞质紧缩,绒毡层延迟解体,不能为核有丝分裂提供能量,致使小孢子败育,最后一同降解。利用2对特异引物扩增Ogura相关基因,在不育系NAURWA01、NAURWA13中扩增出与Ogura相关基因分子量相同的特异条带,而在保持系没有任何条带出现。对特异条带回收克隆测序发现与orf138同源性很高,但是在编码区有3个碱基的差异。推测两个萝卜不育系属于OguraCMS的变异类型。

Cytological and molecular study was conducted for identification of cytoplasm in late-bolting radish male-sterile line. The cytological results indicated that the microspore abortion of NAURWA01 was similar to that of NAURWA13. During the pollen mother cell and tetrad stages, no abnormality was detected. After the microspores were released, the tapetum cells bulged by severe cytoplasmic vacuolation, elongated in a radial manner and enlarged abnormally, pressing microspores seriously. The vacuolated and lagged disintegration of the tapetum could not provide energy for mitosis, which result in the microspore degenerated. The related gene conditioning Ogura cytoplasmic male sterility in radish was amplified with two primers. The amplification patterns from the Ogura specific primers were identical between the two CMS lines. The sequence of specific fragment showed highly identity with orf138 besides three nucleotides in the coding region. It could be concluded that the two cytoplasms in CMS lines were variants of Ogura CMS.