Effect of the Chemical Inducer Actigard™ in Inducing Resistance to Bean Leaf Beetle, Cerotoma trifurcata (Forster) (Coleoptera: Chrysomelidae), Feeding in Soybean

Authors

Parimi Srinivas, University of Nebraska-Lincoln
Stephen D. Danielson, University of Nebraska-LincolnFollow

Date of this Version

2001

Comments

J. Agric. Urban Entomol. 18(4): 209–215 (October 2001)

Abstract

Induced resistance in soybean was investigated in the greenhouse using different concentrations of the chemical inducer Actigard™ to determine the influence on feeding preference of bean leaf beetle adults. Treatments of 0 (control), 15, 25, 40, 60, and 80 ppm Actigard™, and artificial defoliation followed by 25 ppm Actigard™ were applied to V1 and V6 stages of soybean plants. Dual-choice feeding preference tests with the bean leaf beetle were used to assess induced resistance. The adult beetles were collected from soybean fields in east central Nebraska 2 to 5 days prior to the feeding preference tests. Pair-wise comparisons of leaflets from Actigard™-treated plants and control plant leaflets demonstrated that Actigard™ at 25 ppm concentration showed lower preference index (PI) when plants were treated at V1 stage. At V6, feeding preferences were not significantly different; however, all PI values for both V1 and V6 plants indicated that the bean leaf beetles preferred the untreated plants over the Actigard™-treated plants.