Biological characterisation of various geographical isolates of potato virus Y inducing superficial necrosis on potato tubers

Abstract

A range of selected PVY isolates that induce superficial necrosis on potato tubers, originating from several countries, were compared with standard strains of PVA, PVV and PVY. Biological properties (e.g., host range, aphid transmissibility and relationships based on cross‐protection between virus isolates) were studied. PVYNN isolates differ from the normal PVYC, PVYN and PVO strains by their ability to infect Capsicum annuum but not Chenopodium amaranticolor and C. quinoa. All PVYNN isolates are transmissible by Myzus persicae, without any significant differences from one standard strain. These additional data confirm that these tuber‐necrosing isolates belong to PVY. However, they could be ranged in a homogeneous and distinct group inside the PVYN group, based on the differences revealed in the host range, in addition to the specific ability naturally to induce necrosis on tubers.

Effect of plant genotype, virus isolate and temperature on the expression of the potato tuber necrotic ringspot disease (PTNRD)

“…Four PVY NTN isolates, previously selected (Le Romancer et al, 1994), were used (Table 1). They were maintained on Nicotiana tabacum cv.…”

“…Weidemann (1985) assumed that PTNRD could be due to the emergence of a new PVY strain or could result from the influence of particular environmental conditions, probably of hot and dry summers as existed in Hungary and Germany in 1983. Subsequently, the PVY isolates associated with PTNRD were shown to differ from the standard PVY N strain on the basis of their host range, particularly by their ability to infect pepper (Le Romancer et al, 1994) and by their pathogenicity on potatoes. Indeed, previous experiments have shown that these isolates were able to overcome the resistance gene Ny dms (inherited from Solanum demissum), upon sap inoculation.…”

Sequence polymorphism in the 5'NTR and in the P1 coding region of potato virus Y genomic RNA

“…The PVY N strain induces typical 'tobacco veinal necrosis' of Nicotiana tabacum whereas the PVY ° strain induces a non-necrotic mosaic on this host. Some PVY N isolates are the sole cause of potato tuber necrotic disease (Le Romancer & Kerlan, 1991); these isolates share biological properties that distinguish them from classical PVY N isolates (Le Romancer et al, 1994). They are referred to as PVY ~TN isolates [NTN = isolates belonging to the necrotic group (N) of PVY and inducing tuber necrosis (TN)], according to a decision of the European Association of Potato Research Virology Section.…”

Potato virus Y: An Evolving Concern for Potato Crops in the United States and Canada

“…1 . PVY NTN isolates were originally named for their ability to cause potato tuber necrosis in addition to tobacco veinal necrosis (2,6,48,65,93). They apparently arose from both recombination (32) and mutation events (45,59).…”