Wageningen, The Netherlands
May 14, 2008
Source: Plant Research International B.V
Results from a joint
European research project show that seed transmission of
Pepino mosaic virus (PepMV) in tomato is possible, albeit at
a low level. Transmission rates ranged from 0.005 to 0.057
percent depending on the interval between PepMV infection
and seed harvest. This means that the use of seeds harvested
from PepMV-infected plants bears the risk of obtaining PepMV
infected seedlings. This clear conclusion to the PEPEIRA
research project will be entered into the Pest Risk
Assessment.
PEPEIRA is short for ‘Pepino mosaic virus: epidemiology,
economic impact and pest risk analysis’. It is a project
within the EU framework programme 6 and the project
coordinator is PRI scientist René van der Vlugt. Twenty
partners are involved, including PRI and Wageningen UR
Greenhouse Horticulture. The programme was set up to study
the epidemiology and economic significance of PepMV in order
to create a reliable and scientifically-founded analysis of
the risks it poses to the European tomato industry.
 Results
from a joint European research project show that seed
transmission of Pepino mosaic virus (PepMV) in tomato, even
though at a low level, is possible. The seed transmission rates
differed from 0,005% until 0.057% depending on the time interval
between PepMV infection and seed harvest. This means that the
use of seeds harvested from PepMV infected plants bears the risk
of obtaining PepMV infected seedlings. This conclusive
indication of the PEPEIRA research project will be entered into
the Pest Risk Assessment that will be one outcome of this
research project.
PEPEIRA is a research project in the 6th framework programme of
the EU, that aims at developing an EU-wide Pest Risk Assessment
(PRA) for Pepino mosaic virus (PepMV) in tomato. The project
studies the epidemiology and the economic impact of PepMV in
order to provide a robust and scientifically sound assessment of
the risk that PepMV poses to the European tomato industry. To
unravel the highly debated, putative role of seed transmission
in the spread of PepMV, an extensive trial on seed transmission
has been carried out.
More than 100,000 seeds were harvested from PepMV infected
tomato plants in a Belgian greenhouse trial, following an
International Seed Health Initiative approved seed harvesting
procedure comprising acidification and enzymatic treatment. The
virus inoculum was originally obtained from a commercial tomato
crop, naturally infected by both the European tomato strain and
the Chili2 strain of PepMV.
Close up of Pepino mosaic virus (PepMV) in tomato
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Close up of Pepino
mosaic virus (PepMV) in tomato |
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The seeds were distributed to ten
PEPEIRA consortium members from ten different countries and
subsequently germinated and grown in glasshouses or plastic
tunnels, in plots of 10 seedlings each. Between 4 and 5 weeks
after germination, pooled leaf samples from each plot were
collected and analysed for the presence of PepMV using a
standardized ELISA method.
Nearly 90,000 tomato seedlings germinated and were included in
the virus test. Twenty-three out of in total 8.778 plots (87.780
seedlings) tested were positive for PepMV, resulting in a
average seed transmission rate of 0.026 %. The obtained PepMV
seed transmission rates differed according to the time interval
between PepMV infection in the mother plants and seed harvest.
Seeds harvested 8 weeks after PepMV inoculation resulted in a
seed transmission rate of 0,005%, while seeds harvested 15 weeks
after PepMV inoculation resulted in a significantly higher
transmission rate of 0,057%. Positive test results were
confirmed by an additional ELISA-test. The results clearly show
that seed transmission of PepMV can occur, even though at a low
level, and that use of seeds harvested from PepMV infected
plants bears the risk of obtaining PepMV infected seedlings.
This conclusive indication of seed transmission of PepMV, even
though at a low level, will enter into the Pest Risk Assessment
that will be one of the outcomes of the PEPEIRA project.
The Pepeira research project is a collaboration between 20
laboratories and institutions involved or dealing with plant
health from 17 European Countries. More information about the
consortium, the members and the research project:
www.pepeira.wur.nl.
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Pepino
mosaic virus: epidemiology, economic impact and pest
risk analysis |
PEPEIRA is an RTD activity aimed at developing an
EU-wide Pest Risk Assessment (PRA) for Pepino mosaic
virus (PepMV). The proposal will investigate the
epidemiology and economic impact of PepMV in order
to allow a robust and scientifically-justified
assessment of the risk posed by this pathogen to the
European tomato industry. This includes a true
assessment of the economic impact on tomato crops
growing in Member States with different climatic and
market conditions and the role of seed transmission
in the spread of PepMV.
The project will also address the increased risk
posed by new, biologically and genetically distinct
strains of PepMV that have appeared in Europe and
elsewhere recently and have the potential to be far
more damaging. The proposal will also address the
issue of developing validated diagnostic protocols,
to be published via EPPO that can be used with
confidence by National Plant Protection
Organisations (NPPOs) within the EU and laboratories
in other countries that trade with the EU.
In addition to a
strong and focussed science program, the proposal
also mobilises an impressive consortium, including
all EU laboratories with a proven track record of
PepMV research, with extensive plant virus and plant
health expertise from all Member States where PepMV
poses a potential risk.
Consultation with the principle stakeholders (Plant
Health Standing Committee, DG SANCO, growers and
seed companies etc.) throughout the life of the
project is given paramount importance. Adoption of
the new PRA will allow EU Plant Health services to
develop, via Council Directive 2000/29/EC, a
consensus on appropriate measures to prevent PepMV
becoming significant detrimental to the EU tomato
industry.
This in turn will help to prevent any negative
impacts on the sustainability of European
horticulture and other negative economic and social
effects associated with the further establishment of
this disease. |
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More information about the
consortium, the members and the
research project:
www.pepeira.wur.nl. |
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