Plant viruses in the system of seed potato production

Abstract

Solanum tuberosum L. is susceptible to 40 different virus species and 2 viroids. To prevent plant viruses from spreading in field conditions, it is necessary to have reliable data on the species composition of plant reservoirs of viral infection, the total activity of insect vectors, and possible ways of virus transmission in a particular territory of seed material production. Attention should be paid to the factors that facilitate and hinder the disease development in crops and to disease symptoms in different potato varieties. Manifestations of viral infections were monitored on every plant from the sample at the stages of initial growth, bud formation, and flowering and before the removal of potato haulms. Insects were collected using standard entomological method. The total RNA was isolated employing commercial kits for the extraction of nucleic acids from plant material “PhytoSorb” (Syntol Llc) and the benchtop automated extraction instrument KingFisher Flex (ThermoScientific) with magnetic particles. Plant viral infection was observed to accumulate if potato planting material was not renewed. The tested potato plants contained mixed viral infection, which consisted of viruses from mosaic group: PVY, PVX, PVM, PVS PVA, as well as PSTVd and PLRV. Without the renewal of seed potatoes, the concentration of plant viruses in an agroecosystem rises and causes secondary infections in potato plants. The research identified the main insect-vectors in the agroecosystem of potato fields: insects from genera Cicadella, Henosepilachna vigintioctomaculata, Dolycoris baccarum, Mythimna separata, Lygus pratensis, and Rhopalosiphum padi. Many wild weeds serve as fodder plants for insect vectors facilitating the accumulation of plant viruses in agroecosystems. It was established that perennial weeds were the main plant reservoirs of dangerous viral infections, e.g. Sonchus arvensis and Taraxacum officinale. We determined that Trifolium pratense typus L., Chenopodium album L., Plantago major L., Barbarea vulgaris W.T. Aiton, and Ambrosia artemisiifolia L. were the reservoirs of PVY. All these factors can lead to an epiphytotic situation.