Pepino Mosaic Viurs Resistant Tomato Research

Tackling A Tough Foe

Like many greenhouse tomato growers, Michael Bledsoe has long battled Pepino mosaic virus (PepMV). Bledsoe is the vice president for scientific and regulatory affairs for Village Farms, one of the largest greenhouse tomato growers in the world, with operations in West Texas and British Columbia. “Pepino mosaic virus is fairly ubiquitous, certainly,” he says. “To not have Pepino is more rare than to have it.”

But its familiarity doesn’t make PepMV any more palatable. “If it comes in the middle of a cropping cycle, you can lose a whole week’s production,” he says. “A week’s production is $55,000 for a 20-acre greenhouse, and we have 270 acres, so you can see it can be a very devastat-ing problem.”

What makes PepMV even more insidious, says Bledsoe, is that it seems to exacerbate any other problem in the greenhouse. Bledsoe, who designs all of Village Farms’ IPM programs, has seen it time and again. “Pepino makes everything else worse,” he says.

Differing Strains

Because of his experience with PepMV, Bledsoe has become a big fan of USDA-Agricultural Research Service (ARS) scientist Kai-Shu Ling, who is attempting to develop a tomato that can stand up to attack by PepMV. For years, Ling has been studying the origins and evolution of PepMV, which can damage tomato fruit, stunt growth, and leave the plant vulnerable to other infections.

Two PepMV strains that infect tomato plants in the U.S. show a distinct genetic divergence from strains that infect tomato plants in Europe. Ling, who works at the ARS U.S. Vegetable Laboratory in Charleston, SC, studied the genetic makeup of some PepMV strains found in South America, where the virus was first found. He wanted to see if he could tease out the relationships between the PepMV strains found in Europe, South America, and the U.S.

When Ling examined the makeup of U.S. PepMV strains, he observed a strong similarity to the South American strains. One U.S. strain exhibited almost 99% of the same DNA sequence as a South American strain. Another U.S. strain shared almost 91% of its genetic traits with a different South American strain. However, European strains only shared from 78% to 86% of the genetic characteristics found in South American strains.

Giving Growers Hope

Ling also identified three varieties of wild tomatoes with a range of genetic resistance to PepMV. He used the most robust of these varieties to generate new progeny that remained symptom-free after they were exposed to PepMV strains found in South America.

Ling will now use this symptom-free variety to see if he can create a tomato plant with genetic resistance to two U.S. PepMV strains. If he succeeds, he will try to develop a tomato type that has a more general resistance to the European strain of PepMV.

Bledsoe, for one, is rooting him on. “Kai has helped us answer if it’s a new virus, and with phytosanitation procedures,” he says. “But if he could build in some resistance in the future, that would be an even bigger deal.”

Taking No Chances

Village Farms, one of the world’s leading hydroponic tomato growers, takes the doctor’s orders. The doctor in this case is Ling, Ph.D., a USDA-Agricultural Research Service plant pathologist, who recommends that greenhouse growers be very careful when it comes to sourcing their seed. Much more so than with field-grown tomatoes, viruses can really run wild in the greenhouse, so the best way to avoid a virus is to prevent it from ever getting inside in the first place.

“Make sure you source only from reputable companies; don’t buy cheap tomato seed,” says Ling. “Make sure the seed is tested and certified.”

Bledsoe, who holds a doctorate himself, says Ling is one of the leading authorities on such viruses. Because Village Farms doesn’t want to take risk with any of their 270 production acres, he takes Ling’s advice to heart. “Every seed that comes in now gets tested by an independent lab,” says Bledsoe.

If a seed were to test positive for a certain virus, it gets sent off to a university or other research center that specializes in the virus or viroid for DNA sequencing. For example, were a seed to test positive for Pepino mosaic virus, Village Farms would send the seed to Ling.

It’s worth the extra time and expense, says Bledsoe, especially with some of the rarer, more devastating viroids where greenhouse finds trigger a red alert. “We will take that infected plant out and all the other plants around it out,” he says. “We treat it like the plague.”

Leave a Reply

Featured Stories
Citrus stew courtesy of Irma
Citrus
October 19, 2017
Disaster Relief: Ways Florida Growers Can Find Farm Aid
With billions of dollars lost to Irma, financial assistance will be crucial for many. Read More
Fruits
October 19, 2017
New Online Tool Helps Growers Determine Need for Groundwater Recharge
California Land Use Viewer can help growers determine if they can adopt groundwater recharge practices on their own operations. Read More
subirrigation implementation
Irrigation
October 19, 2017
Northeast Florida Farmers Stepping up to Save Water
Green light given to nine agricultural projects steeped in stewardship. Read More
Vegetables
October 18, 2017
The 2018 State of the Vegetable Industry Survey Is Now Open!
How has this year performed for you? Share how things have gone this year – and your expectations for 2018 – in our shorter, more focused survey. Read More
Citrus
October 18, 2017
How to Keep Track of Climate Change
Use cool tools to find out how your production methods may change in the future, how much your area is at risk, and how to limit your own impact on the climate. Read More
Vegetables
October 18, 2017
Stop Viewing Fellow Growers as the Enemy [Opinion]
Instead, growers should focus on issues that benefit everyone, from gaining a stronger voice when negotiating with retailers, to finding a way to share ideas and costs on precision agriculture tools. Read More
Citrus
October 17, 2017
USDA Issues Disaster Declaration for Hurricane-Stricken Florida Farmers
Operators in designated counties eligible for emergency assistance. Read More
Fruits
October 17, 2017
Hirst Named American Society of Horticultural Science Fellow
Honor was presented during society’s annual meeting. Read More
Crop Protection
October 17, 2017
EPA Takes Steps to Reduce Risk of Drift-Related Herbicide Injury
With reports of dicamba injuries in tomatoes, peaches, grapes, and other crops, the agency works to reduce the impact of spray drift on vulnerable crops. Read More
Fruits
October 16, 2017
New Broad-Spectrum Herbicide Released by Nufarm
Grapple herbicide works on pre- and post-emergent weeds in orchards and vineyards. Read More
Flooded peach and grape groves from Irma at UF/IFAS HAEC
Citrus
October 16, 2017
Wrath of Hurricane Irma’s Rainfall Measured by the Trillions
Report says storm dropped enough gallons of water on Florida’s St. Johns River Water Management District to swamp 6.7 million football fields. Read More
Checking hop cones at UF/IFAS MREC
Fruits
October 14, 2017
USDA Seeks Applications for Next Round of Specialty Crop Research Grants
SCRI grants to total $48 million for 2018 fiscal year. Read More
Grapes
October 13, 2017
Fairgrounds Host California Fire Evacuees
Gallo will contribute $1 million to fire recovery effort and will match employee donations two-for-one. Read More
Fallen citrus fruit in wake of Irma
Citrus
October 12, 2017
Irma Rains Down on Florida Citrus Crop Estimate
Initial USDA forecast reflects the fruits of what was left behind by monster storm. Read More
Grapes
October 10, 2017
Wildfires Hit California Wine Country
California Gov. Jerry Brown declares state of emergency for northern counties impacted by flames. Read More
The Latest
Citrus
October 19, 2017
Disaster Relief: Ways Florida Growers Ca…
With billions of dollars lost to Irma, financial assistance will be crucial for many. Read More
Fruits
October 19, 2017
New Online Tool Helps Growers Determine …
California Land Use Viewer can help growers determine if they can adopt groundwater recharge practices on their own operations. Read More
Irrigation
October 19, 2017
Northeast Florida Farmers Stepping up to…
Green light given to nine agricultural projects steeped in stewardship. Read More
Vegetables
October 18, 2017
The 2018 State of the Vegetable Industry…
How has this year performed for you? Share how things have gone this year – and your expectations for 2018 – in our shorter, more focused survey. Read More
Citrus
October 18, 2017
How to Keep Track of Climate Change
Use cool tools to find out how your production methods may change in the future, how much your area is at risk, and how to limit your own impact on the climate. Read More
Vegetables
October 18, 2017
Stop Viewing Fellow Growers as the Enemy…
Instead, growers should focus on issues that benefit everyone, from gaining a stronger voice when negotiating with retailers, to finding a way to share ideas and costs on precision agriculture tools. Read More
Citrus
October 17, 2017
USDA Issues Disaster Declaration for Hur…
Operators in designated counties eligible for emergency assistance. Read More
Fruits
October 17, 2017
Hirst Named American Society of Horticul…
Honor was presented during society’s annual meeting. Read More
Crop Protection
October 17, 2017
EPA Takes Steps to Reduce Risk of Drift-…
With reports of dicamba injuries in tomatoes, peaches, grapes, and other crops, the agency works to reduce the impact of spray drift on vulnerable crops. Read More
Fruits
October 16, 2017
New Broad-Spectrum Herbicide Released by…
Grapple herbicide works on pre- and post-emergent weeds in orchards and vineyards. Read More
Citrus
October 16, 2017
Wrath of Hurricane Irma’s Rainfall…
Report says storm dropped enough gallons of water on Florida’s St. Johns River Water Management District to swamp 6.7 million football fields. Read More
Fruits
October 14, 2017
USDA Seeks Applications for Next Round o…
SCRI grants to total $48 million for 2018 fiscal year. Read More
Grapes
October 13, 2017
Fairgrounds Host California Fire Evacuee…
Gallo will contribute $1 million to fire recovery effort and will match employee donations two-for-one. Read More
Citrus
October 12, 2017
Irma Rains Down on Florida Citrus Crop E…
Initial USDA forecast reflects the fruits of what was left behind by monster storm. Read More
Grapes
October 10, 2017
Wildfires Hit California Wine Country
California Gov. Jerry Brown declares state of emergency for northern counties impacted by flames. Read More
Citrus
October 10, 2017
Impressions from Irma Indelible on the F…
Striking images from the field reveal not only the storm’s destructive nature, but also paths to recovery and reconstruction. Read More
Crop Protection
October 9, 2017
Field Scouting Guide: Black Rot of Brass…
Follow these tips for spotting and treating Xanthomonas campestris. Read More
Citrus
October 9, 2017
(We Won’t Back Down … ) Stan…
You don’t have to be a super hero, rock star, or award-winning scientist to aid farming. You can help by supporting professionalism in fields. Read More