Disease-Infected Thrips Feed More

Thrips — tiny insects that pierce and suck fluids from tomatoes, strawberries, and hundreds of other plant species — show altered feeding behavior when they’re infected with tomato spotted wilt virus (TSWV), newly published research by University of California (UC) scientists reveals.

Male Western flower thrips (Frankliniella occidentalis) infected with TSWV fed up to three times more than uninfected males, according to the research, published this week in the Proceedings of the National Academy of Sciences (PNAS) by UC-Davis plant pathology doctoral candidate Candice Stafford and entomologists Gregory Walker of UC-Riverside and Diane Ullman of UC-Davis.

“Until now, behavioral changes in plant virus vectors have been observed only as a response to plant-host infection, and there have been no examples of vector infection with a plant virus altering feeding behavior,” the scientists wrote.

“Since plants do not move around to come in contact with one another, virus transmission from one host plant to another was a major hurdle for plant-infecting viruses to overcome,” said Walker, UC-Riverside professor of entomology. “To overcome this problem, most plant viruses have exploited the mobility of herbivorous insects, especially piercing-sucking insects, as a vehicle for transport from one plant to another.”

Walker said the study “demonstrates for the first time that a plant-infecting virus not only uses an insect for transport from an infected host to a new host, but also manipulates the behavior of the insect on the new host in order to maximize the probability that it will be successfully inoculated.”

Earlier research showed that males transmit TSWV more efficiently than females and that animal-infecting members of the virus family, Bunyaviridae — in which TSWV is classified — alter the feeding of their vectors.

Compelled by this knowledge, the UC scientists asked whether TSWV, a plant-infecting bunyavirus, may modify the feeding behavior of its vector, the Western flower thrips. When they examined infected and uninfected male and female thrips, infected males made almost three times more probes into the plants than uninfected males, including three times more non-ingestion probes (probes in which they salivate, but leave cells largely undamaged).

“These probes are especially important because TSWV infection requires a functional cell, so this probing behavior is predictive of virus transmission,” said Ullman, UC-Davis professor of entomology and associate dean for undergraduate academic programs in the College of Agricultural and Environmental Sciences.

“I have always been intrigued by how parasites alter the behaviors of their vectors, and thought it was odd that such behavioral alterations have not been reported for vectors of plant infecting viruses,” said Stafford, whose major professor is Ullman. “Although several plant viruses infect their insect vectors, we have shown that vector infection by a plant virus alters feeding behavior, which has major implications for virus transmission.”

An increase in the number of times an insect probes into a plant increases the probability of virus transmission, the scientists noted. “Uninfected male thrips make very few probes and therefore their feeding behaviors are not conducive to virus transmission,” said Stafford. “However, when male thrips are infected with TSWV they make up to three times more probes than uninfected males and are more efficient vectors than female thrips. We hypothesize that this increase in feeding may also result in increased nutrition to counterbalance negative impacts virus infection has on fitness.”

Said Ullman: “We were also fascinated by the possibility that modification of vector-feeding behavior could be a conserved trait among plant and animal-infecting members of the Bunyaviridae that evolved as a mechanism to enhance virus transmission. The outcome of our research deeply underscores the evolutionary importance of vector behavioral modification to parasites infecting hosts in both plant and animal kingdoms.”

The research was supported by the UC-Davis College of Agricultural and Environmental Sciences and the graduate program of the UC-Davis Department of Plant Pathology.

Click here to read the full article.

Source: University of California Newsroom

Leave a Reply

Featured Stories
Apples & Pears
February 21, 2017
Snow Doesn’t Stop Day 1 of IFTA Conference
While the Wenatchee, WA, area has experienced higher-than expected snowfall, tour-goers trudge on to learn the latest about advanced production systems and high-value apple varieties. Read More
Grapes
February 18, 2017
Sustainability Is a Growing Factor in Wine Purchasing
California Sustainable Winegrowing Alliance updates certification program, shows sustainability is important part of wine trade. Read More
citrus psyllid closeup
Insect & Disease Update
February 18, 2017
The War on Citrus Psyllids Still Raging
Despite control challenges, keeping the pest in check remains the best approach to managing HLB. Read More
IMPAC.org screenshot
Citrus
February 17, 2017
How Precision Agriculture Is Helping Farmers Win Over Consumers
New Florida-based organization is seeking to break down barriers between farmers and shoppers by providing a platform to not only show what is grown, but how it's grown. Read More
Grapes
February 17, 2017
Washington Organization Rebrands Itself
Washington Association of Wine Grape Growers unveils new identity at convention, now known as Washington Winegrowers Association. Read More
Registration area at the 2017 Florida Blueberry Growers Association Spring Meeting
Berries
February 17, 2017
Florida Blueberry Growers Counting on a Comeback
With last season's disaster in the rear view, all eyes are searching for bluer skies. Read More
Agras MG-1 agriculture drone
Equipment
February 17, 2017
Wanted: Tech Innovators for Drone Challenge
Land O'Lakes Prize offers up $150,000 to help make drones more useable for farmers Read More
Fruits
February 17, 2017
Are Drones the Future of Pollination?
Researchers in Japan have turned drones into robot bees as artificial pollinators. Read More
GenNext Growers
February 16, 2017
Young Start-Up Hort Tech Companies Honored
Western Growers Center for Innovation & Technology Scholarships promote sustainability. Read More
GenNext Growers
February 16, 2017
Young Farmer Success Act Reintroduced to Congress
Bill to add young growers to Public Service Loan Forgiveness Program. Read More
The Latest
Apples & Pears
February 21, 2017
Snow Doesn’t Stop Day 1 of IFTA Conferen…
While the Wenatchee, WA, area has experienced higher-than expected snowfall, tour-goers trudge on to learn the latest about advanced production systems and high-value apple varieties. Read More
Grapes
February 18, 2017
Sustainability Is a Growing Factor in Wi…
California Sustainable Winegrowing Alliance updates certification program, shows sustainability is important part of wine trade. Read More
Insect & Disease Update
February 18, 2017
The War on Citrus Psyllids Still Raging
Despite control challenges, keeping the pest in check remains the best approach to managing HLB. Read More
Citrus
February 17, 2017
How Precision Agriculture Is Helping Far…
New Florida-based organization is seeking to break down barriers between farmers and shoppers by providing a platform to not only show what is grown, but how it's grown. Read More
Grapes
February 17, 2017
Washington Organization Rebrands Itself
Washington Association of Wine Grape Growers unveils new identity at convention, now known as Washington Winegrowers Association. Read More
Berries
February 17, 2017
Florida Blueberry Growers Counting on a …
With last season's disaster in the rear view, all eyes are searching for bluer skies. Read More
Equipment
February 17, 2017
Wanted: Tech Innovators for Drone Challe…
Land O'Lakes Prize offers up $150,000 to help make drones more useable for farmers Read More
Fruits
February 17, 2017
Are Drones the Future of Pollination?
Researchers in Japan have turned drones into robot bees as artificial pollinators. Read More
GenNext Growers
February 16, 2017
Young Start-Up Hort Tech Companies Honor…
Western Growers Center for Innovation & Technology Scholarships promote sustainability. Read More
GenNext Growers
February 16, 2017
Young Farmer Success Act Reintroduced to…
Bill to add young growers to Public Service Loan Forgiveness Program. Read More
Fruits
February 16, 2017
New App Helps Fruit Growers Calculate Ch…
App helps growers calculate chill hours based on locations and models and assess physiological needs of fruit crops. Read More
Citrus
February 16, 2017
Food Trends Driving Growth Opportunities…
More niche markets emerging for growers to give consumers what they want and need. Read More
Vegetables
February 15, 2017
Tanimura & Antle Will Now Be Partial…
The third-generation farming company takes employee commitment to the next level Read More
Business Planning
February 15, 2017
Are Retailers Your New Competition?
Target will be following a trend that is already under way in Germany and China: offering shoppers greens that are grown right there in the store. Read More
Citrus
February 15, 2017
Florida Citrus Community Loses Longtime …
John Merritt, known as an innovative grower and staunch industry advocate, was 60. Read More
Farm Management
February 14, 2017
Californians Holding Breath as More Stor…
Nearly 200,000 people evacuated below nation’s tallest dam; even growers have had enough for now. Read More
Stone Fruit
February 14, 2017
Georgia Peach Growers Brace for Low Chil…
Last year trees netted almost 700 chill hours; however, Extension agent expects that figure to drop to 600 hours this year. Read More
Grapes
February 14, 2017
2016 California Winegrape Crush Up 9%
Prices were up 12%, and red wine grapes continue to gain on white wine grapes in popularity, though ‘Chardonnay’ remained king. Read More