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Presence of Wheat dwarf virus, Cereal yellow
dwarf virus-RPV and Barley yellow dwarf viruses
in cereal species in Martonvásár
Dalma PRIBÉK 1 Emil POCSAI 2 Gyula VIDA 1
Ottó VEISZ 1
1 Agricultural Research Institute of the
Hungarian Academy of Sciences, Martonvásár,
Hungary 2 Plant Protection and Soil Conservation,
Fejér County Service, Velence, Hungary
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Protection against viruses

• Agronomical measures
• Insecticides and herbicides against vectors and
  weeds
• Resistant and tolerant varieties

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The most widespread viruses in the central part
of Hungary
Damage and incidence rate of the viruses vary with
Year
Location
Crop
Wheat dwarf virus (WDV) Cereal yellow dwarf
virus-RPV (CYDV-RPV) Barley yellow dwarf
virus-MAV (BYDV-MAV) Barley yellow dwarf
virus-PAV (BYDV-PAV) RMV virus (RMV) SGV virus
(SGV)
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Persistant transmission

• During the acquisition feeding period, virions
  enter the posterior mid-gut, and then pass to the
  haemolymph, and from there to the accessory
  salivary gland, and back to the stylet.
• THE INCUBATION PERIOD
• A considerable time (10-20 days) elapses between
  the acquisition feeding period and the appearance
  of virions in the stylet.
• Starvation and moulting do not influence the
  vector ability.
• Infectious ability remains for a long time, often
  indefinitely.

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The first incidence of cereal viruses abroad and
in Hungary
BYDV 1951 Oswald?Houston California 1966
Szirmai Hungary
WDV 1961 Vacke Czechoslovakia 1988 Gáborjányi
et al. Hungary
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Symptoms - yellowing - stunting - the root
development is poor - tillering is intense - some
of the plants die before heading or harvesting
Natural Host Range

• Barley (Hordeum vulgare L.)
• Rye (Secale cereale L.)
• Oat (Avena sativa L.)
• Triticale (Triticosecale X)
• Wheat (Triticum aestivum L.)
• Etc.

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Aims

• estimate the incidence ratios of the viruses on
  cereals grown in Martonvásár
• compare the results of the 2005 virological
  survey with data for the past four years

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Tested species Winter wheat (Triticum aestivum
L.) Winter barley (Hordeum vulgare L.) Durum
wheat (Triticum durum Desf.) Winter oat (Avena
sativa L.) Triticale (Triticosecale X)
Collection Leaves of cereals exhibiting virus
symptoms Each year 50-50 samples from each
species (exception of 2004 these data were
omitted from the evaluation)
Detection ELISA (Enzyme-linked Immunosorbent
Assay )
Data evaluation two-factor analysis of variance
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Incidence of cereal viruses as a percentage of
virus-infected plants
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Effect of viruses and years, as revealed by
analysis of variance (20012005)
Significant at the P0.1 level n.s.
Non-significant
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Effect of viruses and host plants, as revealed by
analysis of variance (20012005)


Significant at the P0.1 level
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Percentage distribution of the varieties between
2001 and 2005, averaged over all the plants
Sváb (1981)
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Conclusions
The data for 2001, 2002, 2003 and 2005 exhibited
a clear pattern, except 2004 when the number of
virus infected plants was extremely low.
In all four (2001, 2002, 2003, 2005) years WDV,
which is transmitted by leafhoppers, was present
in the highest ratio on all the plant species.
The aphids that transmit the RMV, SGV, BYDV-MAV,
BYDV-PAV and CYDV-RPV viruses were far less
active. No significant differences were found
within these viruses.
In many cases the same host plant was infected
simultaneously by several viruses.
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Thank You For Your Attention!
These data confirm the results of earlier surveys
suggesting that WDV infection was far more
serious than other virus infection in the central
part of Hungary.