南丰蜜橘胚性愈伤组织诱导及其转化研究

摘要∶南丰蜜橘是原产于中国的古老柑橘品种，其果实皮薄而肉甜，深受消费者喜爱，当前南丰蜜橘的品质发生劣变，影响了其商品价值。为采用基因工程育种以改善南丰蜜橘品质，通过诱导其愈伤组织并以其为试材进行了转基因研究。南丰蜜橘自种子实生苗下胚轴处长产生出愈伤组织，挑选胚性愈伤组织进行增殖后，采用根癌农杆菌介导法进行开花相关基因AP1的转化。结果获得22团抗性愈伤组织，平均产出率为7.3团/皿，表明该品种有较高的转化率。抗性愈伤组织经PCR分析、Southern blot检测证实为转化子。本研究结果表明南丰蜜橘胚性愈伤组织是基因工程改良的良好受体，可用于其它基因的转化研究。

Research of Embryogenic Callus Induction and Transformation of 'Nanfeng'Tangerine

Abstract: ‘Nanfeng’ tangerine (Citrus reticulata), favorite for its sweet-fleshed and thin-rind fruit, is one of the oldest citrus cultivars in China. However, the decline of its fruit quality affected its commodity value. In order to explore a rapid and effective breeding programme for cultivar improvement, we performed Agrobacterium-mediated transformation of this cultivar using embryogenic callus induced from hypocotyl of seedling. Ti plasmid pROKII with the Arabidopsis APETALA1 (AP1) gene and a neomycin phosphotransferase II (NPTII) gene was used in this experiment. Totally, twenty-two resistant callus clusters were obtained with a mean number of 7.3 cell lines per plate. Further PCR and Southern blot analysis confirmed that transgenes were integrated into citrus genome. Though we have not succeeded in regenerating whole transgenic plants, this study indicate that embryogenic callus of ‘Nanfeng’ tangerine is ideal explants for genetic engineering.