Several specific plant viruses that cause severe economic loss are transmitted via from diseased to healthy plants via the soil or substrate. Wageningen UR Greenhouse Horticulture and Applied Plant Research investigate the possibilities to use micro-organisms to enzymatically degrade these viruses in soil, substrate or the outside of zoospores of specific vectors of oomycete origin.
In addition, this project focuses on microorganisms that increase the tolerance to plant viruses in the plant resulting in less damage upon virus infection. Several candidate bacteria, fungi and derivatives of commercial products were selected for further research based on an extensive literature review in 2012.
In 2013 methods were developed to study microbial degradation of plant viruses on a laboratory scale. Hereby, a combination of in vitro assays, ELISA and test plants were used. Various microorganisms have been identified that completely inactivate specific plant viruses within 24 hours. Following these encouraging results from the lab, several candidate microorganisms were selected for pot tests in a greenhouse. In these pot tests, soil contaminated with PlAMV, TVX, ToMV and PepMV was enriched with specific bacteria and a fungi. Microbial degradation of plant viruses in the soil and decrease in virus infection is currently studied quantitatively with several types of bait plants.Final goal of this project is to design crop production systems in which micro-organisms are used as a natural, highly effective army against soil transmitted plant viruses. The first experimental results show that this innovative strategy can have high potentials.