Virus-transmitting nematodes on crops cause indirect and direct economic damage. The direct damage is smaller and is caused by the nematode feeding on the roots of the host, while the indirect damage can be quite large. Nepoviruses are primarily parasites of native plants and cause considerable economic damage, especially to fruit trees and grapevines and can even cause the decay of entire fruit trees and vines. To a lesser extent, nepoviruses can also spread physically, through direct contact with plants and via seeds and pollen. The most important route of spread is via their vectors, nematodes of the genus Xiphinema, which are also found in the soil at greater depths (2 - 3 metres) and are very polyphagous, which practically prevents their eradication.
In our investigations of the species Xiphinema rivesi, which occurs in the Vipava Valley, we found that it can transmit tobacco ringspot virus (TRSV) and tomato ringspot virus (ToRSV). This is the first time that we have demonstrated the transmission of the quarantine nepoviruses TRSV and ToRSV by nematodes that occur in Europe.
We are also focussing on researching the interaction between the Xiphinema index nematodes and the Grapevine Fanleaf Virus (GFLV), which is causing increasing damage to grapevine producers in the Primorska region.