ARS | Publication request: Laboratory and open-field tests on Abia sericea (L.) (Hymenoptera: Cimbicidae) - a candidate for biological control of teasels (Dipsacus spp.)

Submitted to: International Symposium on Biological Control of Weeds
Publication Type: Abstract Only
Publication Acceptance Date: May 4, 2011
Publication Date: N/A

Technical Abstract: Invasive teasels (Dipsacus spp.) are widespread in the USA (43 states) and listed as noxious in five states. The cimbicid sawfly Abia sericea (Linné, 1758) is under evaluation as a potential agent for biological control of teasels. Abia sericea lays its eggs under the epidermis of the leaves of Dipsacus plants and the larvae feed on the leaves. Laboratory and open-field experiments to evaluate the host specificity of the sawfly were conducted from 2007-2010 at Agricultural University of Plovdiv, Bulgaria. In the laboratory, potted plants from twelve plant species belonging to the families Dipsacaceae, Caprifoliaceae, Valerianaceae, Apiaceae, Asteraceae, and Brassicaceae were tested in multi-choice oviposition and feeding tests. They were arranged in plastic cages measuring 40x40x20 cm, with each cage containing one Dipsacus laciniatus plant and seven plants of different species. Individual females were released in each cage to oviposit. Number of eggs laid, number of larvae hatching and larval feeding were recorded. Eggs were laid only on D. laciniatus plants with one exception – on Valeriana officinalis, although no larvae hatched from the latter. Larval feeding was observed only on D. laciniatus, Knautia arvensis and Scabiosa sp. (all Dipsacaceae). An open field test was conducted in 2010 with seven plant species from the families Dipsacaceae, Caprifoliaceae, Valerianaceae, Apiaceae, and Brassicaceae arranged in a pseudo Latin square design with a distance of 70 cm between the plants within rows. Third- and fourth-instar larvae were released in June at a rate of 1 or 2 per test plant. Adults were released on the plants several times in June-July to lay eggs. In the open-field test eggs were laid and larvae fed only on Dipsacus lacianiatus.