Harpin protein technology helps plant health and fights nematodes in cotton fields
TOMMY DOLLAR takes a no-nonsense approach to cotton production. The Bainbridge, GA grower will try almost any reasonably-sounding production practice once, but second chances are rare for those failing to demonstrate merit in his fields.
Considering that most foliar-applied cotton inputs either control weeds or pests, regulate plant growth, or provide supplemental nutrition, Dollar was mildly skeptical when trying a product in 2001 that promised none of the above.
He treated a portion of his crop with a foliar spray of Messenger, a unique product that produced promising results in research conducted by Eden BioSciences, the manufacturer. The active ingredient of Messenger is a harpin protein, which the company says provides enhanced plant health and growth, and increased yield.
By mid-season, Dollar saw evidence that treated cotton had better nutrient uptake than untreated cotton left for comparison, and plants had more extensive root systems. At harvest he found that yields were increased by as much as 5%-7% percent where Messenger had been used.
Realizing that he was on to something worthwhile, the Georgia grower made using Messenger a routine practice on his entire crop. For the 2004 season, the product was reformulated and named Messenger STS.
“We saw early on that yield increases were occurring in most cases,” Dollar says, “but another thing that keeps me using the technology is that my fields are more consistent year in and year out than they were in the past.”
Dollar interprets the improvement in crop uniformity as evidence of better plant health. He applies the product any time from the 2- to 4-leaf stage, when it is mixed with Roundup for over-the-top application in Roundup Ready cotton, to pinhead square, when he mixes it with a mepiquat chloride-based plant growth regulator.
“I think we benefit from this technology in almost all fields,” Dollar says. “The greatest gains are in our higher-yielding cotton. Percentagewise, the increase seems to be greater in cotton yielding 1,000 pounds of lint per acre compared to that making only 500 pounds.”
In more than 20 EUP trials during 2004, cotton treated with ProAct tank mixed with glyphosate at the 2- to 4- leaf stage outyielded untreated checks by an average of 11%. One of these tests was conducted by crop consultant Billy Bryant, Greenwood, Mississippi. Cotton was treated with ProAct tank mixed with glyphosate at the 4-leaf stage.
There was a 14% increase in average open boll weight at the 1-ounce rate, and an even greater increase at the 2-ounce rate, Bryant adds.
At presstime, Eden was expecting ProAct to be registered in time for use during the 2005 growing season.
N-Hibit seed treatment, a second new product incorporating harpin protein technology, is already registered for use. It targets the nematode problem that’s causing increasing concern among cotton growers. In numerous trials, numbers of root knot and reniform nematode eggs on cotton roots have been curtailed substantially as a result of treating planting seed with N-Hibit.
University of Arkansas studies showed a 55% decrease in root knot nematode eggs, for example. Much of this research was detailed at this year’s Beltwide Cotton Conferences.
Eden research suggests that N-Hibit complements other key components of an overall nematode-management strategy, including selection of cotton varieties having some degree of nematode tolerance.
Two formulations are available this year. N-Hibit CST is offered for use by seed dealers in treating cottonseed, and there’s also an N-Hibit hopper box seed treatment.
Beginning this year, harpin protein technology is designated by the term Harp-N-Tek.