Comparison of Lygus elisus Van Duzee and Lygus hesperus Knight (Hemiptera: Miridae) Feeding Injury to Pre-bloom Cotton

Abstract

Feeding injury and abscission of 6th, 9th and 11th node, first-position cotton squares exposed to Lygus hesperus Knight and L. elisus Van Duzee for 24 h were investigated in field and laboratory studies in 2001 and 2002. Square abscission was not significantly different for L. elisus or L. hesperus in six separate field trials over 2 yrs; however, the control was significantly lower in abscission in two of the six trials. Final square abscission averaged across the 2 yrs was 82.5% for the control, 90.0% for L. hesperus, and 86.3% for L. elisus. Square injury, as measured by estimating the surface area affected by Lygus feeding, was significantly higher for L. elisus compared with L. hesperus in three of the six of trials (6th node in 2002, 11th node for 2001 and 2002) indicating that, in some cases, L. elisus damage is higher than L. hesperus. However, when seed-cotton yield was obtained from squares that did not abcise, there was no significant difference for the control or the two Lygus species. This result was similar to other published studies of infesting cotton with L. lineolaris (Palisot de Beauvois) where yield compensation negated any differences in yield when infested cotton was compared to the control. Lygus elisus, a little known and often misidentified plant bug pest of Texas High Plains cotton, should be considered as damaging as L. hesperus.