What is in this article?:
- Keeping young cotton healthy key for Virginia growers
- Ask for cool germ numbers
• After last year’s problems with a late tropical storm and hurricane, Virginia growers are looking for ways to get their crop up early in the 2012 season, and, hopefully, make up for some of the lost production from the storms in 2011.
• An often asked question among farmers growing cotton in the northern ranges of production is, “Do I need more protection against early season diseases than the standard seed treatments provide.”
GOOD SEED and early season insect and nematode management are needed to get cotton up and growing.
Ask for cool germ numbers
Cool germination tests, often referred to as “cool germ” typically are not reported on the seed tag. The seed companies run this test on all seed and the dealer or distributor usually has this information. If not, the value can be obtained by calling the seed company with the lot number of the seed.
In tests with seed treated with Avicta or Aeris, the veteran plant pathologist added two different over-coat fungicide treatments. Neither of these materials provided any improvement in stand or yield, when compared to the standard seed treatments.
Likewise, in furrow treatments of Quadris and Ridomill Gold added to the base treatment didn’t provide any significant improvement over standard seed treatments.
Cotton growers were without an adequate supply of Temik for the 2011 crop and the long-used product will be even more difficult to find for the 2012 season. A generic Temik, MeyMik, appears to have cleared EPA scrutiny, but it will not be available for early season use on cotton for the 2012 season.
Based on this shortage, Phipp’s says growers have some options for protection against early season cotton nematodes and diseases.
Aeris, Avicta and Votivo —a biological seed treatment — are available to growers as seed treatments. Historically, used as a stand-alone replacement for Temik, the seed treatments have not supplied added protection against both early season insect damage and insect-vectored diseases and nematodes.
Counter, widely used for nematode management in corn, is an option for cotton. Larvin, which has the same active ingredient as Aeris applied in-furrow, is another option for nematode management.
Abomectin, the active ingredient in Avicta is also being used as an in-furrow treatment on cotton.
Both Avicta and Aeris provide very low amounts of the active ingredient in the seed. Using the active ingredient in an in-furrow treatment is a way to get more active ingredient used in either seed treatment to the plant, Phipps explains.
“We didn’t expect much thrips control from either of these materials, because neither has shown much activity in the past. But, we needed to look at these materials to try and find something comparable to Temik that will provide nematicidal activity, which these products provide, plus some activity on thrips.
Phipps says neither in-furrow treatment, used in combination with seed treatments were as good as Temik. Counter provided some thrips control, but flower counts were lower with this product.
“We’re not sure why flower counts were lower with Counter. We hope it was just a one-year fluctuation, but it’s something we will have to take a close look at for the 2012 growing season on cotton,” Phipps says.
Perhaps the best management strategy for both nematodes and thrips comes from using nematode resistant varieties and some combination of in-furrow treatments and standard seed treatments for cotton.
Two varieties, Stoneville 5458 and Phytogen 367, both provided significantly higher yields in grower trials in 2011. These fields have high populations of Southern root-knot nematodes and these two varieties had the highest yield, regardless of fungicide/nematicide treatment, Phipps says.
“In scoring the roots, plants from either of these two varieties had significantly less root gauling — not enough to hurt the plants. This is another way to manage nematodes, and using these resistant varieties will likely play a big part in replacing Temik,” Phipps concludes.
You might also be interested in an article on Virginia cotton growers fine-tuning strip-till production. That article can be found at http://southeastfarmpress.com/virginia-growers-fine-tune-strip-till-cotton-production.
A developing problem in Virginia cotton production is the arrival of herbicide-resistant pigweed. Here's the story on that situation: http://southeastfarmpress.com/cotton/glyphosate-resistant-pigweed-arrives-virginia.
As Virginia cotton acreage increases there is a cotton agronomist in the state helping growers find answers to production problems. For that story, visit http://southeastfarmpress.com/cotton/cotton-agronomist-helping-build-acreage-virginia.