Discriminating Ability and Representativeness of Test Locations in the Louisiana Soybean Performance Trials.

The Louisiana Soybean Performance Trials are conducted annually to identify promising soybean varieties that are superior in Louisiana soybean production environments. These trials provide important information to soybean producers and agricultural consultants who are interested in variety selection and recommendations. In 2010, 191 soybean varieties (MG 3, 4, 5, and 6) were tested at 6 locations throughout the major soybean production regions of Louisiana. Test locations included the Dean Lee Research Station near Alexandria, LA, the Northeast Research Station near St. Joseph, LA, the Macon Ridge Research Station near Winnsboro, LA, the Red River Research Station near Bossier City, LA, the Rice Research Station near Rayne, LA, and the Iberia Research Station, near New Iberia, LA. The discriminating ability of the test locations was determined using the mean coefficient of variation of the 191 entries. This allowed for a measure of “relative” variation independent of the mean yield level of the location. A second analysis, using correlation coefficients between individual locations and the 6-location mean, was conducted to determine the representativeness of each of the test locations.