Peanut cultivar response to damage from tobacco thrips and paraquat
Virginia market-type peanut cultivars in North Carolina vary in the number of days following emergence required to reach optimum maturity, and concern over cultivar response to interactions of tobacco thrips (Frankliniella fusca Hinds) damage in absence of in-furrow insecticide and injury from paraquat exist with respect to cultivar selection. Experiments were conducted during 2007 and 2008 to determine if cultivars vary in response to interactions of the insecticide aldicarb (no aldicarb or aldicarb applied in the seed furrow at planting) and the herbicide paraquat (no paraquat or paraquat applied 24 to 28 d after peanut emergence, DAE). The cultivar VA 98R expressed more damage from tobacco thrips than the cultivars Gregory, Perry, or Phillips. Although vegetative growth parameters varied among cultivar, aldicarb, and paraquat treatments, pod yield and market grade characteristics were not affected by the interaction of experiment, cultivar, aldicarb, and paraquat or the interaction of cultivar, aldicarb, and paraquat. Damage from tobacco thrips in absence of aldicarb affected pod yield more than injury from paraquat. The combination of tobacco thrips damage in absence of aldicarb and injury from paraquat lowered pod yield compared with aldicarb-treated peanut either with or without paraquat regardless of cultivar. These data suggest that recommendations on use of aldicarb for tobacco thrips control or paraquat for early season weed control should not vary based on cultivar selection when considering pod yield and market grade characteristics.