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
Fruits
March 29, 2017
Water Allocations in California Deemed Unfair
Tom Nassif of Western Growers objects to a recent announcement that some in California’s Central Valley received only a 65% initial water allocation, while other growers in the region received 100%. Read More
Albert Pieri of Ocean Mist Farms
Vegetables
March 29, 2017
Ocean Mist Farms’ Albert Pieri Dies
Pieri, who worked with Ocean Mist for almost 50 years, was a pioneer in the early days of California Artichoke and Vegetable Growers, which was renamed Ocean Mist Farms in 1995. Read More
Stone Fruit
March 29, 2017
Plum Varieties are Complex and Fascinating [Slideshow]
While diversity in species gives the consumer many options, plums can be a challenge for growers and marketers. Read More
Grapes
March 28, 2017
Understanding the Economics Of Red Blotch in Grapes
An economist and a plant pathologist team up to help growers understand the threshold for action when a vine is diagnosed with the virus. Read More
Apples & Pears
March 28, 2017
Washington State University Offers Powdery Mildew Management Tips
Opening buds may be exposed to overwintering inoculum as temperatures begin to rise. Read More
Nuts
March 28, 2017
How to Determine Optimal Almond Tree Spacing
Determining the proper row spacing for an orchard should be based on more than production and equipment access, and growers should also ponder the number of trees per row. Read More
Apples & Pears
March 27, 2017
It’s a Family Reunion at IFTA
Some of my fondest memories on the road are at IFTA conferences. Read More
Apples & Pears
March 27, 2017
Out of this World Expectations for ‘Cosmic Crisp’ Apple
With millions of trees going into PNW orchards, Washington State growers are betting big on ‘Cosmic Crisp'. The shift in varieties planted and more took center stage when the International Fruit Tree’s Annual Conference met in Wenatchee, WA. Read More
Miss Florida Citrus and Imperial Polk County 2017 winners Paige Todd and Rachel Smith
Citrus
March 27, 2017
Say Hello to the New Miss Florida Citrus
Storied tradition continues with crowning of the industry’s newest advocate. Read More
Irrigation
March 26, 2017
Tips to Maximize Water Efficiency in Your Almond Grove
Editor’s note: Spencer Cooper joined the Almond Board of California last fall as Senior Manager, Irrigation and Water Efficiency. Western Read More
SWD On Raspberry
Berries
March 26, 2017
Outsmarting SWD with Social Media
Entomologist in Kentucky uses social media for pest updates, trap catches. Read More
honeybees
Citrus
March 25, 2017
New Videos Offer Tips on Planting Pollinator Habitats
A new video series on planting flowering habitats is designed to help growers support crop pollinators. Read More
Freeze protected blueberry bushes in Florida
Berries
March 25, 2017
Florida Blueberry Crop Escapes Slap from Late-Season Cold Snap
Freeze protection tactics prove fruitful as local producers look to gain from Georgia’s loss. Read More
Apples & Pears
March 25, 2017
Two MAIA Releases Available for Growers, Hobbyists
‘Crunch-A-Bunch’ is an early ‘GoldRush’ and ‘Bakers Delight’ is a secret ingredient for baking. Read More
Nuts
March 24, 2017
Foreboding Fungus Vexes Almond Growers
In parts of California, almond growers have recently become concerned about Ganoderma root and butt rot. To put this concern Read More
The Latest
Fruits
March 29, 2017
Water Allocations in California Deemed U…
Tom Nassif of Western Growers objects to a recent announcement that some in California’s Central Valley received only a 65% initial water allocation, while other growers in the region received 100%. Read More
Vegetables
March 29, 2017
Ocean Mist Farms’ Albert Pieri Die…
Pieri, who worked with Ocean Mist for almost 50 years, was a pioneer in the early days of California Artichoke and Vegetable Growers, which was renamed Ocean Mist Farms in 1995. Read More
Stone Fruit
March 29, 2017
Plum Varieties are Complex and Fascinati…
While diversity in species gives the consumer many options, plums can be a challenge for growers and marketers. Read More
Grapes
March 28, 2017
Understanding the Economics Of Red Blotc…
An economist and a plant pathologist team up to help growers understand the threshold for action when a vine is diagnosed with the virus. Read More
Apples & Pears
March 28, 2017
Washington State University Offers Powde…
Opening buds may be exposed to overwintering inoculum as temperatures begin to rise. Read More
Nuts
March 28, 2017
How to Determine Optimal Almond Tree Spa…
Determining the proper row spacing for an orchard should be based on more than production and equipment access, and growers should also ponder the number of trees per row. Read More
Apples & Pears
March 27, 2017
It’s a Family Reunion at IFTA
Some of my fondest memories on the road are at IFTA conferences. Read More
Apples & Pears
March 27, 2017
Out of this World Expectations for ̵…
With millions of trees going into PNW orchards, Washington State growers are betting big on ‘Cosmic Crisp'. The shift in varieties planted and more took center stage when the International Fruit Tree’s Annual Conference met in Wenatchee, WA. Read More
Citrus
March 27, 2017
Say Hello to the New Miss Florida Citrus
Storied tradition continues with crowning of the industry’s newest advocate. Read More
Irrigation
March 26, 2017
Tips to Maximize Water Efficiency in You…
Editor’s note: Spencer Cooper joined the Almond Board of California last fall as Senior Manager, Irrigation and Water Efficiency. Western Read More
Berries
March 26, 2017
Outsmarting SWD with Social Media
Entomologist in Kentucky uses social media for pest updates, trap catches. Read More
Citrus
March 25, 2017
New Videos Offer Tips on Planting Pollin…
A new video series on planting flowering habitats is designed to help growers support crop pollinators. Read More
Berries
March 25, 2017
Florida Blueberry Crop Escapes Slap from…
Freeze protection tactics prove fruitful as local producers look to gain from Georgia’s loss. Read More
Apples & Pears
March 25, 2017
Two MAIA Releases Available for Growers,…
‘Crunch-A-Bunch’ is an early ‘GoldRush’ and ‘Bakers Delight’ is a secret ingredient for baking. Read More
Nuts
March 24, 2017
Foreboding Fungus Vexes Almond Growers
In parts of California, almond growers have recently become concerned about Ganoderma root and butt rot. To put this concern Read More
Citrus
March 24, 2017
Marrone Bio Introduces Biostimulant to R…
Haven Anti-transpirant helps to reduce transpiration of fruit, nut, and vegetable crops. Read More
Citrus
March 23, 2017
Count Down the World’s Top 30 Agricultur…
Familiar names and several new faces among annual ranking’s elite. Read More
Pest Control
March 22, 2017
Fear of GMOs is Impacting Quality Food R…
Perhaps the greatest threat to our industry is a public that values instinctual opinion over careful research and the findings of experts who have dedicated years to their field of study. Read More