Comparison of beetle feeding preferences in an interspecific Salix hybrid

Brenden Armstrong1, 2, Fred E. Gouker2, Gregory M. Loeb3, Lawrence B. Smart2

1Dept. of Horticulture, Kansas State University, Manhattan, KS 66502

2Horticulture Section, School of Integrative Plant Science, 3Dept. of Entomology, Cornell University, Geneva NY 14456

Imported willow leaf beetle (Plagiodera versicolora Laicharting) and Japanese beetle (Popillia japonica Newman) damage shrub willow (Salix spp.) destined for bioenergy production by defoliating them during feeding, which could lead to yield losses. Caged feeding trials in greenhouses were conducted to compare preferences among five genotypes of shrub willow, Salix koriyanagi clone ID SH3, Salix purpurea clone ID 95058, and three progeny of those two clones in the family 99239. Field-captured imported willow leaf beetle and Japanese beetle adults were released onto potted plants arranged in free choice and no-choice experiments to assess the genotypic differences of leaf damage caused by herbivory. The amount of foliage consumed among genotypes was not significant with regards to the imported willow leaf beetle experiments, whereas there were significant differences in the amount of herbivory by Japanese beetles among genotypes, with preference for SH3 and 99239-020, and little feeding on 95058. Differences in feeding preference of different beetles on the same willow genotypes warrants further study of the mechanisms of resistance. You should aim for ~200 words – no more than 225.