抗菌肽基因导入桑树获得抗病转基因植株

TRANSFORMATION OF MULBERRY COTYLEDONS BY CECROPIN GENE AND REGENERATION OF TRANSGENIC PLANTS RESISTANT TO Pseudomonas solanacearum DOWSON

用携带抗菌肽基因的农杆菌处理桑子叶，在含有羧苄青霉素（Cb）400～500mg／L和卡那霉素（Km）20mg／L的MS培养基上，有32.4％的子叶产生了不定芽；66.5％的不定芽在含有Cb300mg／L和Km30～40mg／L的培养基中,正常生长成2～3cm高的新稍；新梢在含Cb50mg／L和Km10mg／L的生根培养基中有72．6％形成完整根系。3次转化共获得12个株系55株KmR植株。不同株系桑苗叶片DNA点杂交分析显示，7个株系有阳性杂交信号。KmR株系桑苗的抗病性测定显示，5个株系共14株桑苗对青枯病具有较强抗性.

Mulberry cotyledons were treated with agrobacteria of which plasmids carried cecropin gene. of the cotyledons treated, 32. 4% formed adventitious buds on MS mediacontaining 400 ~ 500 mg/L of carbenicillin (Cb) and 20 mg/L of kananycin (Km);66. 5% of the adventitious buds grew normally and developed into shoots of 2~3 cmhigh on MS media containing 300 mg/L of Cb and 30~40 mg/L of Km; 71. 2% of theshoots formed healthy root systems in 1/2MS media containing 50 mg/L of Cb and 10mg/L of Km. A total number of 55 Kmk plants which belonged to 12 lines were obtained. Dot blot assay to DNA of the 12 lines showed that 7 lines had positive hybridization signals. Inocluation with bacteria Pseudomonas solanacearum Dowson showed that14 transgenic plants of 5 lines had strong resistance to the infection.