The Biology and Host Specificity of Liothrips sp. (Thysanoptera: Phlaeothripidae), an Agent Rejected for Biocontrol of Annual Ragweed

An unidentified species of Liothrips causing severe damage to Ambrosia elatior was collected in northern Argentina. In field surveys, the species was found only on A. elatior and occasionally on the closely related plants Parthenium hysterophorus and Xanthium spinosum. In tests, development was completed on very young seedlings of sunflower (Helianthus annuus), which were severely damaged. Based on these results, the species was rejected as a potential biocontrol agent for ragweed (Ambrosia artemisiifolia) in Australia, even though there is no record of attack on sunflower crops in Argentina.