转chit42基因柠檬的分子鉴定及抗炭疽病研究

Molecular identification of chit42 transgenic lemon and study on its resistance to Colletotrichum gloeosporioides

以转chit42基因柠檬为试材,对其进行了分子鉴定和抗炭疽病研究。用PCR和Southern杂交证实外源基因chit42已经整合到转化植株基因组中,chit42基因在转基因柠檬SR23株系中为3个拷贝,在SR24株系中为2个拷贝。对转基因柠檬进行离体和活体抗炭疽病试验表明转基因柠檬抗炭疽病能力得到明显提高。利用半定量RT-PCR技术检测chit42基因在柠檬中的表达,结果表明用炭疽病病菌接种处理24h后,chit42基因表达量开始增加;接种48h后,chit42基因表达量进一步明显增大;接种72h后,表达量开始有所下降,但仍然高于正常情况下chit42基因的表达量。

The chit42 transgenic lemon was used as material for identifying its molecular characterization and studying its resistance to Colletotrichum gloeosporioides. The chit42 gene was integrated into the lemon genome by PCR and Southern blot. Southern blot results revealed that three and two copies were inserted to SR23 and SR24 transgenic lemon clones, respectively. The transgenic clones of lemon were in vitro and in vivo tested for disease resistance to Colletotrichmn gloeosporioides. The transgenic plants showed significantly higher resistance than the control plants by delaying the development of disease symptoms. The expression of chit42 gene in transgenic lemon was detected by using semi-quantitative RT-PCR,which indicated that the expression of chit42 gene enhanced within 24 h after inoculation of Colletotrichum gloeosporioides, and significantly increased at 48 h, then decreased at 72 h but stilly higher than untreated control.