Genetic transformation experiments of the different explants from Citrus grandis cv. Changshou Shatian You infected with Agrobacterium rhizogenes were carried out in darkness or in light. The optimizing culture system...Genetic transformation experiments of the different explants from Citrus grandis cv. Changshou Shatian You infected with Agrobacterium rhizogenes were carried out in darkness or in light. The optimizing culture system of Ri T-DNA transformed roots for C. grandis cv. Changshou Shatian You was constructed as follows： After the ventral wounded striations on the single activation cotyledon were inoculated by A. rhizogenes A4 （logarithmic period）, they were cocultured at （25 ±2）℃ in darkness for 25-30 days; some transformed roots were generated from wounded striations of most cotyledons. The genetically transformed ratio is （83 ± 11）%. Axenic Ri T-DNA transformed roots （hairy roots） were harvested after five subcultures. Explants were activated on MT medium. The MS medium was used for subculture of transformed roots. Mass Ri T-DNA transformed roots in which the hormone was produced independently were harvested from this optimizing culture system. White, fresh Ri T-DNA transformed roots were （1.14 ±0.07） cm long, （0.73 ±0.04） mm wide, and the growth direction of transformed roots was negative geotropism.展开更多
以易发生汁胞粒化的老龄树和不易发生汁胞粒化的适龄树的琯溪蜜柚(Citrus grand is(L.) Osbeck‘Guanxi-miyou’)果实为材料,研究了果实成熟过程中汁胞粒化发生与细胞壁代谢的关系。结果表明:老龄树果实的汁胞粒化指数随着果实成熟而上...以易发生汁胞粒化的老龄树和不易发生汁胞粒化的适龄树的琯溪蜜柚(Citrus grand is(L.) Osbeck‘Guanxi-miyou’)果实为材料,研究了果实成熟过程中汁胞粒化发生与细胞壁代谢的关系。结果表明:老龄树果实的汁胞粒化指数随着果实成熟而上升。在汁胞粒化发生过程中,汁胞维持较低的细胞壁降解酶[果胶甲酯酶(PE)、多聚半乳糖醛酸酶(PG)、纤维素酶(Cx)]活性,保持较高的细胞壁物质(原果胶、纤维素、半纤维素)含量;尤其在汁胞粒化的起动阶段和加快阶段,纤维素、半纤维素含量极显著增加。相反,适龄树果实的汁胞粒化指数在果实成熟过程中变化不大,汁胞中细胞壁降解酶活性较高,促进原果胶、纤维素、半纤维素等细胞壁物质的降解,保持较低的细胞壁物质含量,使汁胞发育正常、柔软多汁。这说明PE、PG、Cx活性和原果胶、纤维素、半纤维素含量与琯溪蜜柚汁胞粒化密切相关。展开更多
基金The research was supported by the Science Fund of China Post Ph.D （2003034492）Science Foundation of Chongqing Educational Committee （040216）, China.
文摘Genetic transformation experiments of the different explants from Citrus grandis cv. Changshou Shatian You infected with Agrobacterium rhizogenes were carried out in darkness or in light. The optimizing culture system of Ri T-DNA transformed roots for C. grandis cv. Changshou Shatian You was constructed as follows： After the ventral wounded striations on the single activation cotyledon were inoculated by A. rhizogenes A4 （logarithmic period）, they were cocultured at （25 ±2）℃ in darkness for 25-30 days; some transformed roots were generated from wounded striations of most cotyledons. The genetically transformed ratio is （83 ± 11）%. Axenic Ri T-DNA transformed roots （hairy roots） were harvested after five subcultures. Explants were activated on MT medium. The MS medium was used for subculture of transformed roots. Mass Ri T-DNA transformed roots in which the hormone was produced independently were harvested from this optimizing culture system. White, fresh Ri T-DNA transformed roots were （1.14 ±0.07） cm long, （0.73 ±0.04） mm wide, and the growth direction of transformed roots was negative geotropism.
文摘以易发生汁胞粒化的老龄树和不易发生汁胞粒化的适龄树的琯溪蜜柚(Citrus grand is(L.) Osbeck‘Guanxi-miyou’)果实为材料,研究了果实成熟过程中汁胞粒化发生与细胞壁代谢的关系。结果表明:老龄树果实的汁胞粒化指数随着果实成熟而上升。在汁胞粒化发生过程中,汁胞维持较低的细胞壁降解酶[果胶甲酯酶(PE)、多聚半乳糖醛酸酶(PG)、纤维素酶(Cx)]活性,保持较高的细胞壁物质(原果胶、纤维素、半纤维素)含量;尤其在汁胞粒化的起动阶段和加快阶段,纤维素、半纤维素含量极显著增加。相反,适龄树果实的汁胞粒化指数在果实成熟过程中变化不大,汁胞中细胞壁降解酶活性较高,促进原果胶、纤维素、半纤维素等细胞壁物质的降解,保持较低的细胞壁物质含量,使汁胞发育正常、柔软多汁。这说明PE、PG、Cx活性和原果胶、纤维素、半纤维素含量与琯溪蜜柚汁胞粒化密切相关。
