EDITOR’S NOTE — Organizers of the Farm Press Peanut Profitability Award have reviewed production data from previous winners to arrive at a “Top 10 Keys to Peanut Profitability.” This list of successful production practices will be presented in descending order during the next several months in issues of Southeast Farm Press and on this website, with sponsorship provided by DuPont Crop Protection. The Peanut Profitability Award, based on production efficiency in whole-farm situations, is entering its 13th year and is administered by Marshall Lamb, research director for the National Peanut Research Laboratory, and his staff.
Coming in at No. 10 and 9 in the “Top 10 Keys to Peanut Profitability” are two production practices that are closely related — twin rows and planting date.
Both of these practices have changed over the years in an effort to battle the threat of tomato spotted wilt virus (TSWV), and they continue to evolve with the introduction of genetically improved peanut cultivars.
No. 10: Twin rows
“We still think that the twin-row pattern overall, in multiple years with multiple trials, still works the best, and our new cultivars are still responding positively just as our older varieties did,” says John Beasley, University of Georgia Extension peanut agronomist.
“We have been looking at 30-inch single rows, since we have growers who are planting corn in that pattern, and we have found that 30-inch rows will work, but the trick is getting them dug properly,” he says.
“The biggest trick there is that you end up with 2,900 extra linear feet per acre, which at six seed per foot or row, is going to increase your pounds per acre planted. If you’re planting 36-inch singles, you need to back up your seeding rate from six seed per foot to five seed per foot.”
Seeding rates continue to be tweaked, says Beasley, because new cultivars come out that grow differently and have different yield potential.
“We’ve tested the seeding rates for these new large-seeded cultivars, and on a single-row pattern, we’ve seen where we can back down to five seed per foot of row and save costs without sacrificing yield.
“So when we get one answer, then we have to go back to the drawing board. We have to evaluate all of these new cultivars on factors such as twin versus single rows, conventional versus reduced tillage, different planting dates and populations, and calcium requirements, to name just a few.”
Row pattern is an important consideration in deciding the seeding rate, says Scott Tubbs, University of Georgia cropping systems agronomist.
“For single-row peanuts, you’re planting a seed at 12 inches or 1 foot of row. You’ve got six seed per foot being planted — that’s a seed every 2 inches from an adjacent seed being planted. In a twin-row pattern, we’re taking out half of those seed and moving them over to an adjacent row.
“Looking at data from 2011 trials, 85 percent of our twin-row peanuts had survived by the end of the season. Seventy-three percent of the peanut seed in single rows survived. We used the same seeding rate and the same management,” he says.
Part of the decrease in single-row plant stands is due to plant competition, and part of it is due to the speed of the seed plate as it’s spinning, says Tubbs, adding that there will be skips whenever you plant at too rapid a speed.
“We’ve typically seen twin rows yield better than single rows,” he says. “This isn’t in every single case, but the vast majority of time, we’ve seen from a 200 to a 500-pounds-per-acre increase in twin rows.”
As with many peanut production practices, the popularity of twin rows grew in response to producers’ need to best combat diseases, particularly TSWV.
Research on irrigated peanuts has shown a strong tendency for significantly higher yields, a one to two point increase in grade, and reductions in spotted wilt severity that have averaged 25 to 30 percent.
Row pattern, either single or twin rows, also has some effect on the potential for disease in a field.
In work at the Coastal Plain Experiment Station in Georgia, white mold was more severe in single (six seed per foot) than in twin rows (three seed per foot). White mold often develops in a field by infecting sequential plants within the same row.
Planting the seed in twin rows rather than single rows increases the distance between the crowns of the peanut plants and delays the spread of white mold from plant to plant.
No. 9: Planting date
Recommended planting dates for Southeastern peanut producers have shifted, primarily due to the availability of new varieties that are more resistant to certain disease pests.
“Our shifting planting dates are definitely cultivar related,” says Beasley.
“Georgia Green was great when it was released in the mid-1990s, but it needed help as far as TSWV was concerned. We found in our research we had to plant it later, we had to maybe put it in twin rows, and we had to get a higher population to help reduce the risk of TSWV, even though it had better resistance than the varieties we were planting previously, including Florunner and GK-7.”
The cultivars available to producers today, including Georgia-06G, Georgia-07W, Georgia Greener, Florida-07 and Tifguard, all have considerably better resistance to TSWV than Georgia Green, he says.
“In our trials, we found we can go back and start planting in April, which will allow some of our growers to plant earlier,” says Beasley.
“Some growers prefer to plant peanuts earlier because that is when they have adequate moisture in the ground. In many cases, if they have to wait until May 15, they may lose that moisture.”
In the past, recommendations called for waiting until the first of May or later to plant to help reduce the incidence of TSWV.
“We hammered that point home, year after year. Before the onset of TSWV, we were planting 25 to up to 40 percent some years in the month of April, and finishing up by about May 25.
“When we started seeing pressure from TSWV, we were planting less than 5 percent of our acreage in April, and maybe 70 percent into May and into the remainder of June. It created some severe logistical problems for growers as far as timing their harvest before threatening colder weather,” says Beasley.
“At first, we were concerned about planting more of our peanut acreage in April. But looking at the data, with the outstanding cultivars we now have available, and considering they have better resistance to TSWV than Georgia Green, growers now have the flexibility to go back and plant earlier,” he says.
Planting later, however, can lead to trouble, he adds. “If you don’t start planting your crop until June 5, June 10 or June 15, you run the risk of risk of getting to Oct. 15 or Oct. 20, and having temperatures so cold the crop doesn’t mature properly. That’ll reduce your yield and grade.”
Beasley says he’d like to see 25 to 30 percent of Georgia’s peanut crop planted in April, as long as the soil temperature is at least 65 degrees F. or higher for several consecutive days.
(For an introduction to the "Top 10 Keys to Peanut Profitability" see http://southeastfarmpress.com/peanuts/top-10-keys-peanut-profitability-will-be-shared).