Ecology, epidemiology

- Conservation, sources of viruses

The specter of hosts virus Y de la pomme de terre ( Potato virus Y , PVY) semble limité aux solanacées Cultivation : pomme de terre, poivron tomato, aubergine and tabac, ainsi drop diverses mauvaises herbes ( Solanum nigrum, Portulaca oleracea, Senecio vulgaris, Physalis spp ) ensuring among other things its winter conservation. Other plants are : likely to host it Cyphomandra betacea, Datura ferrox, D. innoxia, Nicandra physaloides, Nicotiana glauca, N. rustica, Petunia spp., Physalis angulata, P. heterophylla, P. mendocina, P. virginiana, Schizanthus retusus, Solanum andigenum, S. atropurpureum, S. aviculare, S. cardenensii, S. gracile, S. indigena, S. jasminoides, S. khasianum, S. laciniatum, S. sisymbrifolium, S. xanthocarpum , and more recently Hyoscyamus niger .

Species belonging to other dicotyledonous families are also susceptible to this virus: Dahlia variabilis, Rudbekia amplexicaulis, Senecio vulgaris, Brassica sp., Quisqualis indica, Cassia occidentalis, Medicago arabica, Melilotus officinalis, Melilotus sp., Plantago lanceolata, Ranunculus asiaticus, Tropaeolum majus, Viola tricolor

In temperate regions, potato regrowths are the main virus reservoirs, but other perennial plants such as Cyphomandra betacea, Nicandra physaloides, Solanum nigrum and S. dulcamara can play a comparable epidemic role. It is the same for weeds like Solanum atropurpureum , as well as other Solanum , in tropical and subtropical zones.


- Transmission, dissemination

At least 40 aphid species are capable of transmitting PVY, according to the non-persistent mode : Myzus persicae, M. certus, Aphis gossypii, A. fabae, A. craccivora, Acyrtosiphon pisum, Brachycaudus helichrysi, Macrosiphon euphorbiae, Phorodon humili, Rhopalosiphum insertum, R. padi ). The virus is very quickly acquired by the insect vector; a few seconds and a low number of viral particles are sufficient to ensure efficient transmission. However, transmission by aphids requires the presence in infected cells of a protein of viral origin: the helper factor, or helper component (HC). Only viral particles acquired in the presence of this factor are retained in the maxillary stylets and are likely to be transmitted. However, the efficiency of transmission depends on both the aphid vector and the virus strain.

This virus is also mechanically inoculable in several plants that are members of the Chenopodiaceae, Amaranthaceae, Fabaceae and Asteraceae families, in addition to the Solanaceae. It does appear not to be transmitted by contact or by seeds .