棉花转基因恢复系杂种F1小孢子发生的细胞学观察

对转gst基因棉花恢复系浙大强恢"配制的杂种F1(三系杂交棉)的成熟花药和花粉育性进行了研究.结果表明,在花药的长、宽、鲜重和成熟花粉粒的育性方面,浙大强恢"所配的F1和保持系DES-HAB277"接近,无显著性差异,但比受体恢复系DES-HAF277"所配的F1分别提高47.7%、61.8%、28.5%和39.6%.以不育系DES-HAMS277"和保持系DES-HAB277"的花药为对照,对浙大强恢"和受体恢复系所配的F1的小孢子发生进行了细胞学观察发现,不育系小孢子败育主要发生在造孢细胞增殖期和小孢子母细胞形成期,且在减数分裂期彻底败育,不能形成四分体;受体恢复系所配的F1在小孢子发生和雄配子形成的各个发育时期都有部分败育,平均败育率约为20%,且主要发生在小孢子母细胞减数分裂期和小孢子单核期;而浙大强恢"所配的F1与保持系一样,花药的发育、小孢子的发生以及雄配子的形成均正常.研究结果从细胞形态学方面证明gst基因对三系杂交棉具有防止部分小孢子败育和提高花粉育性的功能.

Cytological Observation of Microsporogenesis of Hybrid F1 Derived from Male Sterile Line and Transgenic Strong Restorer in Upland Cotton

"Zheda strong restorer",a transgenic restorer,developed by transferring glutathione s-transferase(gst) gene into a restorer "DES-HAF277",had overcome weak restorability of the recipient restorer.When this transgenic restorer was used as a male parent and crossed with the CMS lines "DES-HAMS277",its hybrid(F1) anthers had the same length,width and fresh weight and percentage of viable pollens as the maintainer "DES-HAB277",but enhanced 47.7%,61.8%,28.5% and 39.6% when compared with hybrids(F1) derived from the recipient restorer.Cytological observation of microsporogenesis of the CMS line,the maintainer and hybrid F1s derived from the transgenic strong restorer and the recipient restorer indicated that:the abortion of the CMS line mostly took place at the sporogenous cell division and mother microspore cell meiosis stage without the tetrad formation;hybrid F1 derived from the recipient restorer had about 20% aborted male cells in anther.Its abortion mostly took place at the uninuclear and binuclear microspore stage;the microsporogenesis of hybrid F1 derived from the transgenic strong restorer was normal as the maintainer.These results indicated that gst gene over expression in anther could enhance pollen fertility of hybrid F1 in the cell morphological aspect.