In 1967, the average U.S. peanut yield was 1,765 pounds per acre. Fifty years later in 2017, the average U.S. peanut yield more than doubled to 4,074 pounds per acre.
How were U.S. peanut farmers able to make such impressive gains over these 50 years?
One key factor is the work of the American Peanut Research and Education Society (APRES) that brings together peanut scientists and others in the peanut industry to address the challenges of producing peanuts and to find ways to boost yields. APRES is celebrating its Golden Anniversary this year.
In an address to the APRES annual meeting in Williamsburg, Va., Dr. Corley Holbrook, supervisory research geneticist at the USDA-ARS Coastal Plain Experiment Station in Tifton, Ga., noted that before APRES was formed in 1968, peanut yields were never above 2,000 pounds per acre. Since APRES was formed, peanut yields have increased 46 pounds per acre per year to more than 4,000 pounds per acre today.
“It would not have been achieved without the existence of APRES, which played a big role in helping researchers and Extension agents to do what they do so we can increase yields for peanut producers,” Holbrook said at the APRES gathering.
Up to the 1950s, U.S. peanut yields were relatively stable and didn’t grow that much. Holbrook said this was due to peanuts being a regional crop and the states and federal government weren’t providing much funding for research and Extension.
That began to change in the late 1950s. Holbrook considers this the first Golden Age for U.S. peanut production as improvements in chemical control of pests and diseases came about and improved varieties were released. He also considers this the first Golden Age for peanut research and Extension with an increase in funding and more scientists working in the discipline.
Holbrook notes that APRES was formed in 1968 as state and federal governments increased funding for research and Extension. Those involved in the work saw the need for a forum to share information, develop cooperative arrangement and disseminate research results.
The forerunner of APRES, the Peanut Improvement Working Group, was organized in 1957; the original membership consisted of representatives form USDA, land grant universities and the peanut industry.
This group evolved into an organization representing the diverse interests of the peanut industry, and in 1968 the PIWG was dissolved and the American Peanut Research and Education Association was founded. In 1979, the organization’s name was changed to the American Peanut Research and Education Society.
“The annual meetings were critical for people to get together, talk about what they were doing and share ideas. Also critical was the formation of Peanut Science where a lot of people were publishing their research information,” Holbrook said.
Holbrook also credits the work of Frank McGill, Georgia’s peanut agronomist from 1954 to 1982, who spearheaded and championed the “package approach” for peanut production, a multi-discipline way of solving problems still used today. McGill was an active leader in APRES from its formation.
Holbrook said McGill and his Extension colleagues did a good job of disseminating research information to growers so they could maximize yields. In fact, Holbrook stressed, Extension was critically important for the strong yield gains.
“I’ve traveled some throughout the world. I think what has made U.S. agriculture such a shining star compared to a lot of countries is that we put as much emphasis on Extension as we do on research. We take the information and get it to growers,” Holbrook said.
A major factor in the impressive yield gains was development of new cultivars from the 1940s to the 1980s. During this time, USDA ARS established breeding programs in all three peanut producing regions. In addition, changes in production practices and improvements in disease control methods form the late 1980s to early 1990s helped yield gains.
“The contribution of cultivar development was about 13 pounds per acre per year” Holbrook explained. “The new cultivars were higher yielding because they were earlier maturing, had a higher harvest index, had less vegetative mass and a shorter main stem. They had an increase in allocation of photosynthesis to reproductive structures and an easier transition from vegetative to reproductive growth.”
However, in the mid-1980s, U.S. peanut yields began to decline. Holbrook said a key factor in that yield drop was the loss of the most effective nematicide to control root knot nematode. Also contributing the yield decline was an increase in peanut acreage that disrupted effective rotations.
“Most important was the emergence of tomato spotted wilt virus. For anybody around in the late 80s and early 90s, it’s not an exaggeration to say that this virus could have wiped out the peanut industry in the Southeast,” Holbrook said.
“All of the varieties we were growing were very susceptible. It was bad, but I think all of the researchers and all of the Extension people pretty much dropped most everything else they were doing and said ‘we have to see what we can do about this.’”
Holbrook said breeders across the Southeast were fortunate because they had access to the peanut line P1203396, collected in Brazil in the 1950s and used for leaf spot resistance, but it also had resistance to tomato spotted wilt virus.
P1203396 was used to develop varieties with resistance to tomato spotted wilt virus, and within a few years two varieties were released that offered resistance to the disease.
Also, Holbrook said plant pathologists determined that going from planting four seed per row foot to planting six seed per row foot reduced the severity of tomato spotted wilt virus. Also, severity was greater if peanuts are planted before May 1 or after June 1.
“They recommended an optimum planting window and developed the tomato spotted wilt virus risk index. Growers s could use that to minimize their risk of tomato spotted wilt. We were able to stabilize the yield and preserve the peanut industry in the Southeast,” Holbrook said,
During this period, a large percentage of the papers presented at the APRES meeting dealt with ways to minimize the severity of tomato spotted wilt virus. APRES was vital in getting a handle on the disease, Holbrook said.
Holbrook considers this the second Golden Age of peanut research and Extension. Beginning in 2000, overall U.S. peanut yields began to show strong gains again.
“We are now building off that base, and we are going into what I think is a third Golden Age for peanut research and Extension and a second Golden Age for U.S. peanut production,” Holbrook said.
“Contributing to that third Golden Age is the continued development and release of improved cultivars that have much greater resistance to tomato spotted wilt virus. There are cultivars with resistance to root knot nematode and cultivars with improved resistance to other diseases. And we have cultivars with greater yield potential,” Holbrook said.
Improvements in disease control and some improvements in weed control and the use of GPS technology for precision digging is also helping bump up yields.
“We’ve come a long way. We’re in a good place. It’s really exciting with the things that are happening. The impact of genomic technology on cultivar development is very exciting and is having a huge impact. APRES is well positioned to play a big role to facilitate research and Extension for the benefit of the U.S. peanut industry going forward,” Holbrook said