One For The Books

It was a record crop, but not without issues in some areas.

By Amanda Huber

 

With a record crop on the books, there should be little to report in the way of pest problems. This is surprising given the number and timing of tropical storms and hurricanes, which could have made conditions right for heavy disease pressure. Overall, Extension specialists and researchers report good yields and grades, thereby creating the record tonnage.

In the Southeast, producers dodged a bullet with very little Tomato Spotted Wilt Virus pressure, only to be smacked hard by insect pressure.

White Mold Appears Early
Management of diseases is always critical for peanut producers. However, Bob Kemerait, University of Georgia Extension plant pathologist reports there were a few surprises in 2008.

“Losses to tomato spotted wilt were quite low in the Southeastern U.S. last season, and it is estimated that the disease cost growers only about one percent of their total yield,” he says.

While that was good news to the region, Kemerait says white mold (stem rot) was particularly destructive in 2008, and management was a problem for many growers.

“I believe that very warm soil temperatures in June resulted in a situation where white mold got an early jump on the peanut crop,” he says. “Throughout much of the 2008 season, many growers were battling white mold.”

Kemerait says that although rains from Tropical Storm Fay created nearly ideal conditions for the spread of leaf spot disease, it was not a major problem in most fields.

Budworms Would Not Budge
What producers saved on disease management, they spent on insect pest management, which David Adams, UGA entomologist, says was costly to Georgia growers in 2008.

“Tobacco budworms developed treatable levels on peanuts that were only six inches wide, especially in fields under conventional cultivation,” he says. “Many fields had three generations of budworms at action levels.”

Adams says control failures due to resistant populations resulted in multiple applications of insecticides to control a single generation of budworms, and that added greatly to the cost.

“High populations of threecornered alfalfa hoppers and spider mites were especally problematic in non-irrigated peanuts,” he says. “And, the burrower bug continued its climb to notoriety in strip-tilled, non-irrigated peanuts. Many of these fields yielded segregation-two grades.”

Rotation Improves Alabama’s Yields
Kris Balkcom, Auburn University Agri-Program Associate, says that Alabama producers received rain at the right time and cooler temperatures were the norm this year.

“We did not have but one day over 100 degrees this season compared to last year when we experienced 14 consecutive days over 100 degrees,” he says.

Besides favorable weather, Balkcom also says yields are increasing because of improved rotation schemes by producers.

“Alabama has improved its rotation by planting 40,000 to 50,000 fewer acres to peanuts the past several years,” he says.

An early frost did catch some producers with peanuts still not harvested, but they waited for the cold weather to pass before continuing to harvest, and little damage occurred.

The result was that Alabama made a record crop in 2008.

Timely Rains In South Carolina
After a generally dry spring and early summer in 2008, the South Carolina peanut crop received timely rains in July continuing through pod fill into September, says Jay Chapin, Clemson University Extension entomologist. The result was another state with a record crop.

Chapin says the primary disease problems were from the usual suspects: tomato spotted wilt, white mold (stem rot) and late leaf spot.

“Of these three, white mold pressure was above average, with virus and late leaf spot pressure about typical,” he says. “Early leaf spot was more prevalent than normal, but less of an economic factor than late leaf spot.”

Chapin reports that Cylindrocladium Black Rot is an increasing problem on new peanut land.

“DNA and ALS-resistant pigweed continues to be the major weed management problem,” he says. “Insect problems were minimal except for the losses caused by thrips-vectored spotted wilt disease. We also had a few segregation-two reports from burrower bug injury.”

Chapin adds that failed inoculation on some of the new peanut was the major non-pest agronomic issue in 2008.

“Every year has its challenges, but the crop is determined by getting water during July and August podfill and not getting it during October harvest,” he says. “We had excellent rain during podfill and a good, though not great, harvest season.

“Rain shut things down for a week in October, causing some late harvest losses from over-maturity; and early frosts reduced late-season quality on what was still an overall excellent crop.”

Further up the eastern seaboard, Virginia’s producers harvested 23,000 acres at an average yield of 3,400 pounds per acre.

Maria Balota, assistant professor of crop physiology at Virginia Tech, says at the Tidewater AREC, rainfall was nine inches less than the annual average.

“Temperature, including soil temperature, was optimum for growth and development, and accumulated heat units over the peanut growing season exceeded 2,900 degrees Fahrenheit.”

Cool Weather In Southwest
It may be better to say that it was not desert-like in the Southwest than to say it was cooler, but temperatures were not in the normal range in 2008, and maturity was affected.

Chad Godsey, Oklahoma State Extension peanut specialist, says the 2008 peanut production season in Oklahoma produced excellent yields, but maturity and, therefore, grades were affected by cooler weather.
Pod set was typical until August when temperatures started to decrease.

“A large number of peanuts were set in late August due to below-normal temperatures,” he says. “Temperatures continued to stay below normal, which slowed down maturity.”

Godsey says this decreased grades of runner varieties, but most of the Spanish and Virginia varieties graded at or slightly above average.

“Although grades were a little lower on average, yields will most likely beat last year’s state average of about 3,300 pounds per acre.”

No major widespread insect pest problems were observed during the 2008 growing season, but disease pressure was high, especially late in the season. Godsey says Sclerotinia pressure was high in infected areas of the state, and there was a fairly large amount of pod rot in the western part of the Oklahoma peanut production region.

A Wind-Whipped Year
Naveen Puppalla, New Mexico State University, says that cool temperatures and high winds delayed the crop in New Mexico, and it stayed two weeks behind because of lower heat until accumulation.

“Rains after digging have hampered grades in few locations,” Puppalla says. “Overall, it is an average year for yield at about 2,500 pounds per acre.”

New Mexico produces most of the Valencia peanut market, and Puppalla says demand for Valencia’s has increased.

Texas may have had the most different weather conditions this season. Hot, dry and windy is the best way to describe the early season in Texas. Then, just as the crop was getting started, a hail storm pounded it almost beyond recovery.

Jason Woodward, Extension plant pathologist in Texas, reported seeing Verticillium wilt, Sclerotinia blight and the pod rot complex, plus he says some fields were treated for leaf spot and Southern blight.

Woodward says Verticillium wilt, caused by Verticillium dahliae, is an increasingly important disease in cotton production throughout the southern High Plains and is becoming more evident in peanut fields in the region. Several studies were conducted in 2008 to learn more about the disease and potential treatments, and that information will be used to develop management strategies.

PG