Identification And Detoxification Of The Virus Of Edible Fungi

There are totally more than500kinds of edible fungi in the world, and there are more than350kinds in China. Currently, the production of edible fungus in China is65%of the world’s total one, is the top of all countries in the world. Virus is the important issue in edible fungus production, and it lacks the simple and effective identification and control method for viral disease. This study established a technical system for extraction of viral specific dsRNA from the edible fungus, and analysed the virus genome sequence information by using DOP-PCR, then the treatment for detoxification is also performed to get virus-free strains.1. By using modified SDS method, viral specific dsRNA is isolated from the fungus tissue Boletus sp. and Pleurotus ostreatus. Extracted specific dsRNA fragments are2.5kb,2.0kb and1.8kb, respectively, and the characteristics reveal that the dsRNA is same as one reported in foreign countries. The technology system was established for extraction of dsRNA, and the system can identify effectively the virus. The dsRNA fragments form Boletus are2.0kb,1.6kb and1.4kb, which are not identified because of the shortage of information about virus in Boletus. To identify the virus for marketing fungi, much of them infected by the virus. It indicated that the virus may have been spread widely in the domestic sales with fungi species sales.2. Using dsRNA as template, a non-specific amplification for part of the viral genome is performed with DOP-PCR technology. The products of DOP-PCR are cloned sequenced. Seven sequences are obtained, which is about300～500bp. By using BLAST program, we failed to find the high-similar sequence in GenBank, and there are low similarity with some antifungal protein amino acid sequence (similarity is greater than30%). Among them, only one sequence (clone No. C09sample) indicated high similarity with virus specific sequence. Clone C09is1100bp, and the initial part of sequence (85bp) have97%similarity with RNA1of Cucumber mosaic virus. Generally speaking, Clone C09probably is fungal virus specific sequence, but due to fungal virus sequence is less reported, therefore we are unable to search a high-similar sequence in the database.3. Using chemical reagent-hyphal tip removal processing, low temperature-hyphal tip removal treatment and high temperature-hyphal tip removal processing, the fungi were performed detoxification treatment. There is better efficiency for high temperature-hyphal tip removal treatment, and it can removed the virus form Boletus sp. and Pleurotus ostreatus. The treatment for ribavirin, cycloheximide, virazole and moroxydine hydrochloride combined with hyphal tip removal treatment, weakened virus dsRNA strip. It is likely to interfere with the replication of virus, but the mechanism is not understood.4. The characteristics of growth and laccase, carboxymethyl cellulose for virus-free and virus-effected strains are analyzed. It indicated that the growth potential of virus-free strains was better than the virulent strains, and laccase, carboxymethyl cellulase activity were significantly improved. On the whole, the metabolic activity of strains may be enhanced because the enzyme activity was increased, so it will promote the growth of mycelium.