When peanut growers make a commitment to put a variety in the ground, they make a commitment to live and die with the genetic capabilities of that variety.
Knowing how that variety reacts to stresses during the growing season, and how tolerant it is of different disease problems, can be the difference in profit and loss in peanut production.
It is estimated in the Virginia and northern North Carolina peanut production areas fungicides and nematicides may be as much as 40 percent of the production cost. The first step in managing these costs is to select a variety that is best adapted to the soil type, disease and nematode history and genetic resistance to these pests.
Long time Virginia Tech Plant Pathologist Pat Phipps says peanut growers in the Virginia-Carolina Belt have some options when it comes to variety selection in 2007. With a large increase expected in peanut acreage in Virginia, knowing capabilities of each variety and matching these to a particular set of soil and environmental conditions is important, he says.
One of the new varieties that will be available in limited seed quantities in 2007 is Champs. Developed by Virginia Tech plant breeders, Champs, has been in university testing in several Southern states and has performed well.
Champs is early maturing and as resistant as any Virginia-type to tomato spotted wilt virus. It has a pink seed coat and is early maturing, which can be valuable in sclerotinia management. Though Champs doesn't have resistance to sclerotinia, its early maturing characteristics exposes it to the disease for less time late in the growing season.
“We've seen some serious problems with Champs in some years with heavy sclerotinia pressure. Certainly you don't want to plant it in fields with a history of sclerotinia. It should be planted in fields with a four-year, and not less than, a three-year rotation,” Phipps contends.
Perry is another relatively new variety that has a real good disease package, including one of the best CBR resistance traits of any Virginia-type on the market, and it has some resistance to sclerotinia. In testing over several years, Phipps says Perry shows as many hits from sclerotinia as more susceptible varieties, but there is less damage to the peanuts.
Perry has partial resistance to early leafspot, which has shown up consistently in both Virginia and North Carolina. It also has good web blotch resistance. It also has strong vines, which means peanuts will hold up better, if a grower is delayed getting into a field to dig.
Perry was released by the North Carolina Agricultural Research Service in 2000. It is a large-seeded Virginia-type peanut with a high rating for resistance to CBR and partial resistance to Sclerotinia blight. It is characterized by a semi-runner growth habit.
The major drawback to Perry is late maturity and high susceptibility to tomato spotted wilt virus. “We haven't had a bad tomato spotted wilt virus year in the past two years, but growers need to remember 2002, when the virus was so bad. If we have a bad year for tomato spotted wilt virus, Perry will be one of the varieties at greatest risk,” Phipps says.
Georgia 05E is a large seeded peanut variety that may have some application in Virginia and North Carolina. “We have not tested it in Virginia, but if it has a growing period and habit similar to Georgia Green, it will be difficult to grow here,” Phipps says. Virginia growers who grew limited acreage of the variety in 2007 contend it performed well, but needs to be planted in April.
Gregory is a variety that has been around a few years, and in long rotations and fields with little history of disease problems, it can be a highly profitable variety because of its high percentage of jumbo kernels.
It has an intermediate growth habit between bunch and runner, a pink seed coat, and a high percentage of jumbo pods and extra large kernels. It is susceptible to most diseases and insect pests.
Because of its large seed size, Gregory has a high calcium requirement and may show reduced seedling vigor compared with other varieties.
NC-V11 is the standard Virginia-type variety grown from Virginia to Florida. It was released by the North Carolina Agricultural Research Service cooperatively with Virginia. NC-V11 is a large seeded Virginia-type peanut with good quality factors, and has superior flavor. NC-V11 is high yielding and has significantly higher value than other available varieties. The variety has a runner growth habit, but is slightly erect. Maturity is about 140 days.
NC-V11 is the most disease tolerant of the Virginia-type varieties. In five-year tests by researchers at Virginia Tech's Tidewater Agricultural Research and Extension Center (TAREC), NC-V11 was the most profitable of all the Virginia type varieties tested.
Though not always the highest yielding variety, it has consistently been among the most reliable and profitable Virginia-type varieties grown.
NC-V11 is highly susceptible to web blotch, which has become a bigger problem since the variety was released in 1990. In fields with a history of web blotch, NC-V11 is not a good choice to plant. By comparison, Perry has good resistance and Wilson is moderately susceptible.
Web blotch control is most important in cool, wet weather after Aug. 1. The most effective treatment is Abound or Headline applied once during August and followed by a final spray of chlorothalonil for resistance management.
In addition to its tolerance of web blotch, Wilson is moderately susceptible to tomato spotted wilt virus, leafspot and other diseases common to the Carolina-Virginia Peanut Belt. It is intermediate in maturity and has excellent qualities, such as light hull color and large kernels, for the in-shell market.
In fields with long rotations (three or more years) and in areas with a history of web blotch it may be a good alternative to Gregory because of its high percentage of large and fancy kernels.
Wilson was released by Virginia Tech in 2002. Wilson is a Virginia-type peanut variety with large seed and has an intermediate runner growth habit and pink to light-pink seed coat color and has medium-green color leaves and large-sized leaves.
Brantley is a new variety developed by North Carolina State University. It performed well in the five-year tests conducted by researchers at the Tidewater Agricultural Research and Extension center in southeastern Virginia and was consistently among the highest yielding varieties in the test. Though it was still rated high in profitability, Brantley was not as profitable in the test as NC-V11 among Virginia-type varieties nor Georgia Green among runner types tested.
Brantley was derived primarily by backcrossing NC 7, and it has shown similar disease susceptibility as the one-time favorite variety among Carolina-Virginia growers. It was planted in limited quantities last year and performed well in grower tests.
Growers should consider Brantley to have moderate to high susceptibility to leafspot, Cylindrocladium black rot (CBR), Sclerotinia blight and tomato spotted wild virus.
Brantley is a Virginia-market-type cultivar possessing alternate branching pattern, intermediate runner growth habit, medium green foliage, and large seeds, which average approximately 65 percent jumbo pods and 24 percent fancy pods, and extra large kernel content of approximately 50 percent.
Phillips is another relatively new Virginia-type variety that also performed well in the TAREC tests. Phillips is a Virginia-market-type cultivar possessing alternate branching pattern, intermediate runner growth habit, medium green foliage, and large seeds. Though Phillips is moderately susceptible to the major diseases prevalent in the Carolina-Virginia Belt, it is more closely tied via its breeding line to NC-V11 than the other new Virginia-type varieties. Whether this genetic similarity will mean less disease problems, as is generally the case with NC-V11, remains to be seen.