Dry Weather Worsens Impact of Corn Rootworm Feeding

ST. LOUIS, Mo., Aug. 20, 2007 - Corn rootworms are among the most damaging insects that farmers must battle, and drought conditions in parts of the Corn Belt this season, such as Indiana and Ohio, can exacerbate the impact of this pest.

Under normal conditions, with adequate rainfall, corn plants can withstand a certain amount of rootworm feeding, according to Clint Pilcher, Monsanto Corn Insect Traits Technology Development Manager. But in severely dry conditions, he explained, damaged roots make it more difficult to absorb limited subsoil moisture and nutrients, compromising plant health and yield potential.

"With plenty of moisture, a corn plant can compensate for some feeding, but without adequate moisture, it is less able to recover," Pilcher said.

Pilcher noted that corn hybrids with Monsanto's new YieldGard VT(tm) technology are performing well this season, even under severely dry conditions. Root digs in dry regions show that the YieldGard VT roots are well protected, supporting more efficient uptake of moisture than conventional corn hybrids.

"We are seeing several cases in Indiana and Ohio and parts of eastern Illinois where YieldGard VT Triple(tm) plants are 12 to 18 inches taller than corn protected with soil insecticides," he said. Pilcher noted that dry weather poses a risk even when rootworm pressure is lighter than normal levels. "In dry areas, it doesn't take extreme pressure to observe differences in plant performance," he says.

Pilcher noted that similar results are being seen in 22 stress mitigation plots that Monsanto is monitoring this season across the Corn Belt. To keep out moisture, tents have been erected over the plots which have also been infested with rootworms to determine how YieldGard VT and conventional hybrids respond to insect pressure under dry conditions. At mid-season, YieldGard VT Triple plants were taller and healthier than corn plants with insecticides or no protection.

Pilcher encourages farmers to conduct digs to assess the level of rootworm feeding in their corn fields and if necessary to consider management options, such as in-plant insect protection, for next season.

YieldGard VT technology provides growers with improved consistency, even better insect control and higher yield potential than the first generation of YieldGard® products. YieldGard VT Triple products, planted by about 2,000 farmers across the Corn Belt this season, combine YieldGard VT Rootworm and Roundup Ready® 2 technology with YieldGard Corn Borer.

Individual results may vary, and performance may vary from location to location and from year to year. This result may not be an indicator of results you may obtain as local growing, soil and weather conditions may vary. Growers should evaluate data from multiple locations and years whenever possible.