TITLE:

Peanut Tolerance to Valor applied PRE at AG-CARES, Lamesa, TX in 2002.

AUTHORS:

Peter Dotray, Wayne Keeling, Trent Murphree, John Everitt, Associate Professor, Professor, Graduate Research Assistant, Research Associate

MATERIALS AND METHODS:

             Plot Size:                        4 rows by 50', 3 replications

             Soil Type:                      Amarillo fine sandy loam

             Planting Date:                May 2, 2002

             Variety:                          Flavor Runner 458

             Application Dates:         PRE - May 2

             Rainfall in-season:         4.9 inches

             Irrigation in-season:       15.5 inches

             Digging Date:                October 10

             Harvest Date:                 October 16

RESULTS AND DISCUSSION:

Valor is a new soil applied peanut herbicide that received a Federal 3 label in 2001. During its launch year, peanut injury to Valor was reported. Most of this injury was reported in North Carolina, Georgia, and Oklahoma, but a few fields in West Texas noted some injury. Valor has good activity on a variety of weeds, including annual morningglory species, but it has limited residual activity (lasting approximately 4 to 6 weeks). This study was conducted to evaluate peanut tolerance to Valor when applied at excessive rates. All plots were kept weed-free to insure any visual injury or yield reduction could be attributed to the herbicide and not other factors.

Valor at 0.063 lb/A and 0.094 lb/A (the lower and upper rates on the label, corresponding to 2 and 3 ounces of product per acre, respectively) did not injury peanuts throughout the season. Valor at 0.125 and 0.188 caused no more than 5% visual injury early season, and no injury was observed in August. No Valor treatment caused a peanut yield reduction. We feel that Valor is a good tool for West Texas peanut growers; however, the short residual activity on many weeds including morningglories should be expected. In addition, previously reported injury is believed to be the result of heavy rainfall at the time of peanut emergence (similar to a Caparol splash to cotton cotyledons).