TSWV on Rise in Southeast Peanuts

Clint Thompson Peanuts

Photo courtesy of UGA Extension/Shows tomato spotted wilt virus in peanuts.

By Clint Thompson

One disease of peanuts this year was the worst growers have experienced in the past decade, according to University of Georgia Extension peanut agronomist Scott Monfort. He is cautioning producers about tomato spotted wilt virus (TSWV), which made its presence known in multiple fields this year.

“If you’ve got a significant amount of virus, 50%, 60% or 70% and we do have a couple of those fields, if you’ve got stunted plants, then you’re probably going to see yield loss. You’re probably going to see some grades situations because they’re deformed pods and not nice looking pods. You might have some problems there,” said Monfort.

Various Factors

“I think we have seen a slow tick-up of the virus the last four years, going from almost nothing to several fields being inundated with it and having problems. I think we have built up virus here, and then we have the winter like we did last year where there was no cold weather hardly,” Monfort said. “You don’t kill off a lot of those weeds and they persist. Or you have volunteer plants, and those persist. You’ve got more green material out there that can harbour the virus as well as thrips. That combination I think is what has caused it to be so much this year.

“What we can hope for (in the future) is a real cold winter. Maybe that would knock it back, but we don’t know that.”

TSWV is vectored by thrips, tiny insects that can spread the virus by feeding on infected plants. Infected thrips transmit the virus when they feed on healthy plants. The virus can dwarf plants and cause significant reductions in peanut yields.

It is not too early for growers to consider their management options for next season, many of which exist before plants are put in the ground.

“If it was me, I would take Bob Kemerait’s word to heart. That (Peanut RX), you look at everything on there and see what can you do to put on top of one another; everything you can do to make it work,” Monfort said. “I think you’ve got to do everything you possibly can to minimize that virus.”

He added that there was a significant difference this year in virus instances in peanuts planted before May 10 compared to those planted afterward. Also, twin rows looked better than single rows planted in April.