Variation in Plant Injury and Yield By Lepidopterous Pests in Selected Cultivars of Bt Cottons in New Mexico

7 varieties of Bt cotton were planted in a field trial in Artesia NM as part of a larger collaborative project with Cotton Incorporated and Texas A & M University. Damage to squares and bolls were compared weekly. Yields were picked for two 50 ft center rows. Plants were also removed for yield partitioning comparisions. Square damage to conventional cotton was significantly higher than cultivars with 2-3 Bt genes. Cultivars with one Bt gene had damage that was not significantly lower than conventional cotton.