Advances in understanding the soil-borne viruses of wheat: from the laboratory bench to strategies for disease control in the field

In China, soil-borne viruses transmitted by the root parasite Polymyxa graminis have caused significant yield loss in winter wheat for many years. At present, it is believed that two main soil-borne RNA viruses, namely wheat yellow mosaic virus (WYMV) and Chinese wheat mosaic virus (CWMV) are responsible for such losses. The molecular characteristics and infection processes of these two viruses have been intensively investigated and described substantially in detail, following the complete sequencing of their respective genomes. In this review, we highlight our recent findings on the distribution of WYMV and CWMV in China, the associated crop damage, the biological functions of WYMV and CWMV proteins as well as the viral temperature sensitivities. We also describe the characteristics of the resistance genes and discuss the novel virus–plant arms race strategies in hope of enlarging our understanding on the theme of virus-plant interactions. Finally, we compare current disease-management options and suggest the application of biotechnology-based genetic resistance to develop more cost-effective countermeasures for controlling soil-borne virus diseases in the future.