Stopping the nematode comeback
Problem nematodes were controlled to some degree by soil-applied insecticides until recently, but in the last few years, with genetic Bt crops, very few soil insecticides are being applied. “No granular insecticide applied means more nematode survival and more crop damage,” said Dan Beck, Bayer CropScience, technical sales consultant in Nebraska.
Additionally, nematodes are susceptible to dying in dry soil, but farmers are doing better to conserve soil moisture. “No-till has become extremely common because of the moisture that it saves. So, with the moisture level and no disturbance of the soil, nematodes survive that much better,” noted Beck.
Nebraska’s Extension service has been educating growers about potential nematode damage, but many areas of the country other than Nebraska have extreme nematode pressure and growers have recognized it for years. They just haven’t had excellent control methods.
Robert Henry, farmer and proprietor of Robert Henry Seed Company at New Madrid, Mo., said the research shows that nearly every field crop is a host to different nematodes. “Around here it isn’t uncommon to have 12 to 15 different types of nematodes identified in a soil test specifically checking for nematodes,” he said.
For this reason, Henry was quick to agree to field test the combination of Poncho seed-applied insecticide and VOTiVO biological seed treatment in two fields in 2009 and again with customers on 4,000 acres of soybeans and 1,400 acres of corn in 2010. By combining the two, Bayer CropScience has registered a combination product, Poncho/VOTiVO, that provides protection against early season insects and nematodes.
Henry reported the 2009 trials showed a 26-bushel per acre difference between field sections treated with Poncho/VOTiVO and Poncho 250. The other field showed 13-bushel and 16-bushel higher yields at two check points. Yields averaged 196 bushels and 213 bushels per acres in the two treated sections of irrigated fields. Poncho/VOTiVO contains a naturally occurring bacillus bacteria that is alive but dormant on treated seed until that seed is planted.
“A Poncho/VOTiVO application results in 10 million bacteria spores on each corn seed, and those respond to favorable conditions once the seed is in the soil. As the corn seed germinates, the bacteria exponentially increase. When the roots begin to grow, a huge number of bacteria live on and around the root system. We know that the VOTiVO bacteria, using the exudates secreted by the plant roots as they rapidly grow, multiply and protect the root from nematodes through the important early stage of corn growth when yield potential is established,” explained Ray Knake, Bayer CropScience, Midwest product development manager.
Knake further explained that nematodes live off root exudates, too, but most of them damage the roots, which the VOTiVO bacteria don’t do. “The nematodes sense the exudates from the roots, but if the bacteria is present, there is less exudates for the nematodes. Secondly, through site occupation, the bacteria is also in place in such high numbers around the roots that there is no easily reachable feeding site for the nematodes.”
“It is farmer friendlier for handling,” said Henry. “In working with other nematicide chemicals in the past, we had to wear all types of safety gear.” There is no increase in safety procedures for handling seed treated with Poncho or Poncho/ VOTiVO.
“The safety of the product is impressive. It is a product we needed, and it really works to control nematode damage,” Henry said. Poncho/VOTiVO will be widely introduced on corn seed in 2011, and seed will only be treated commercially.
For more information, visit www.PonchoVOTiVO.us or contact a Bayer CropScience field representative.