Interaction of Peanut Variety and Insecticide1,2

It is generally assumed that insecticide performance is independent of the peanut variety; however, tests conducted for several years indicate insecticide performance is influenced by the peanut variety. The most significant variety-insecticide interaction resulted from systemic insecticides used for control of thrips and leafhoppers on bunch type peanuts. Thimet (phorate) was more effective than Furadan (carbofuran) for thrips control regardless of the peanut variety. Erratic control of thrips and leafhoppers was obtained on bunch, Virginia type peanuts NC Ac 15754, NC Ac 15753, and ‘Shulamit.’ Thimet applied to runner and intermediate growth type peanuts reduced thrips and thrips damage in excess of 90%. Furadan was ineffective against thrips on NC Ac 15754 and gave less than 50% control on Shulamit. Thimet failed to control the potato leafhopper on NC Ac 15753 and Shulamit but gave good control on NC Ac 15754. Furadan which failed to control thrips on NC Ac 15754 gave approximately 50% control of leafhoppers. Furadan which reduced thrips by only 65% on NC Ac 15753 reduced leafhopper damage by 90%. The peanut variety also influenced insecticidal control of the southern corn rootworm. NC Ac 15753 exhibited 2 to 3 times more rootworm damage than ‘Florigiant’ when both peanut varieties were treated with the same rates of insecticides. Diazinon was ineffective against the rootworm on NC Ac 15753 and Mocap performance was significantly reduced when applied on NC Ac 15753. These data indicate the peanut variety should be considered an integral part of an insect control program.