Transcript
Intro
[MUSIC PLAYING]
Oregon's a perfect place to grow grapes.
We've got the perfect climate here,
we've got nice, hot, dry summers,
and then we've got cold, wet winters,
which significantly reduces problems in this grape growing
region.
We've started noticing leaves that are reddening,
that's called red blotch, which is a significant problem here
in the industry.
Red blotch virus reduces the quality of the crop,
and that can ruin a vineyard.
This problem is not treatable at all.
As soon as the virus is in the vine,
you have to take those vines out,
you cannot get rid of the virus out of those vines.
It really impedes the ability of the vine
to photosynthesize normally.
It also lowers multiple other characteristics
that we're looking for in good quality grapes.
What is your work
Hi, I'm Vaughn Walton, I'm an entomologist here
at Oregon State University.
I'm also a core member of the Oregon Wine Research Institute.
And I do work on insect pests here in vineyards in Oregon.
We are looking at insects that are spreading the virus
through the vineyards.
We're getting a better idea of which ones
are the most important ones.
The ultimate goal of the project is
to better understand the virus and to help growers deal
with the virus.
If you don't know what's spreading the virus, how
important insects are, then you wouldn't know
how to deal with the problem.
So we've identified, in some cases,
that the vines have come--
that have been flaunted initially,
have come in with the virus.
And that's part of the problem.
We've already established that.
But we're also showing, through our work, our mapping work,
that the virus is spreading, that there
is a bug that's spreading it.
These insects are known to be tree hoppers,
they're feeding on vines, moving from surrounding vegetation
onto vines.
They will feed on a vine that contains the virus,
they will move that virus from that dirty vine
onto clean vines.
What is the deadly triangle
So in this problem, we've identified
what's called the Deadly Triangle,
and it's nothing different from something
like the Black Plague or the Bubonic Plague.
And in that Deadly Triangle, we've got three components,
we've got the virus, which is red blotch,
then we have the vector, and then the third component,
or the vines, which are all the host plants.
Finding flying insects
So one of the key problems with finding these insects
is actually finding them.
It's a very, very tedious process.
Tree hopper size is about half the size of your pinky nail,
and they're also green in color, and they're usually
feeding on green tissues, which makes
it really difficult to find.
So we did initial work where we were
determining where the virus is found in vineyards.
We found that it's in the edges of vineyards,
and that led us to believe that it's
spread from the edges of the vineyards
rapidly into the vineyard itself.
And so we determined from that, we
guessed, that it's a flying insect.
We identified at least two or three
of those flying insects that are closely correlated to vineyards
where the spread is taking place.
That's where we're at at the moment,
we're looking at those insects, we're
looking at those correlations of spread
from the surrounding vegetation through the vineyard.
We know these bugs have their unique sounds that they make,
and they make those sounds during mating behavior.
And so if you can mimic those sounds,
put that sound somehow in a trap,
itself, we suspect that we'd be able to trap those bugs
way more efficiently, and that'll
be a fantastic risk management tool, we think, in the future.
So that's why the trapping, I think,
is going to be really important.
So you don't have to search on green issues for green--
camouflaged green bugs.
Transmission biology
So this is where we--
in the greenhouse is where we are doing our transmission
biology studies.
We put the insect vectors onto vines
that contain the virus for a preset period,
then we move those bugs over to vines that are
known to be clean of the virus.
That will show us whether the bugs can actually
transmit the virus from dirty vines to clean vines.
There are techniques to amplify the genomic material, which
helps us make those positive tests.
You have reactions that's done with these really sophisticated
machines that basically run through multiple cycles
and it increases the amplitude of the level of the virus.
You get a positive curve that goes up and shows
that the vine has large quantities of the virus in it.
Transmission biology is absolutely important.
You cannot say that a virus is transmitted by a bug if you
don't have controlled conditions where your are showing that
transformation is taking place.
Conclusion
So very often, you'll have growers wanting
to spray pesticides, or they are wanting to disc their weeds off
and stuff like that, but we don't
have the knowledge to tell them, yes, spray or disc the weeds,
or whatever.
We can't say that to them at this stage.
We don't know if that really works,
so we need to determine the biology of the bug
to be able to tell them that certain methods are going
to be helping to deal with the problem.
Without the growers, and without the Oregon Wine Research
Institute, this work would not be possible.
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Vaughn Walton is an entomologist with Oregon State University’s Department of Horticulture, OSU Extension Service and also a core researcher with the Oregon Wine Research Institute. He works with vineyardists who are growing grapes for this area’s booming wine industry. His team has determined three species of insects responsible for spreading red blotch.
Special Thanks to: Bill Boggess, Executive Associate Dean, OSU College of Agricultural Sciences Danielle Gabriel, inspiration for OWRI research video series.
Want to learn more about this topic? Explore more resources from OSU Extension:
Wine grapes, Insects, Integrated pest management
