Transformation Of Watermelon Mosaic Virus Coat Protein Gene And Analysis Of Disease Resistance

Melon is not only high yield,high quality,also high economic benefits,its market range is very wide.It has a long history of cultivation in Xinjiang and also the world's important economic crops.Known as �plant cancer,� said the plant virus disease,is the main reason for the reduction of a variety of crop production,especially in melon crops.Once the virus disease occurrence,it will seriously cut melon production and reduce melon quality,or even crops.And the virus in the field will often compound infection,which makes the prevention and control of viral diseases more difficult.In recent years,Xinjiang melon industry has been influenced by plant viruses,and the main planting melon varieties are not resistant to plant virus diseases,so the source of the virus coat protein gene transformation by genetic engineering technique is a feasible method.The experiments are carried out and the following results are obtained:1.The diseased leaves collected from Turpan,Xinjiang,were identified as watermelon mosaic virus after isolation and purification.Watermelon mosaic virus coat protein(CP)gene.This gene was inserted into p CAMBIA2300 vector after Hind III and Xba I digestion,the plant expression vector was obtained.2.A high efficiency and rapid regeneration system of thick-skinned muskmelon had been set up using cultivars �jiashi� cultured in the mediums with different hormone of 6-benzolaminopurine(6-BA)and silver nitrate(Ag NO3).The MSB medium containing 1.5mg�L-16-BA was the most suitable for inducing adventitious buds with an average rate of 75%.The MSB media containing 1.5mg�L-16-BA+2.0 mg�L-1Ag NO3 was the best suitable for inducing adventitious buds with an average rate of 65%,there were most of single adventitious buds,this combination could save time of regeneration system.3.Many false transgene plant were obtained by Agrobacterium mediated transformation.The genomic DNA of the false positive plants were extracted and identified by PCR.11 transgenic tobaccos and 4 transgenic melons were obtained.4.The enzyme activities of SOD,POD and CAT in transgenic tobacco were detected,and it was found that the activities of these three enzymes were higher than those of wild type tobacco,and it was preliminarily proved that transgenic tobacco had resistance to watermelon mosaic virus,which could be used as an assistant index for early screening of resistant plants.Statistical T1 generation of transgenic tobacco with Kan resistance of genetic segregation ratio of 3:1,and No.1,No.4,No.5,No.6,No.9,No.10,No.11 of the seven strains were obtained.The results of this study laid the foundation for further research on plant disease resistance.