Host specificity of Liothrips ludwigi, a candidate biological control agent of invasive Ludwigia spp. in the USA

Abstract

The host range of the thrips Liothrips ludwigi was investigated using single- and multi-generational no-choice nymphal development and oviposition tests. Development, oviposition, and egg viability were quantified when L. ludwigi were fed three exotic Ludwigia species and seven USA native plant species. Liothrips ludwigi completed development and oviposited viable eggs on sympatric native Ludwigia species and sustained multiple generations on test plant species under laboratory conditions. These results indicate that L. ludwigi is not sufficiently host-specific for further consideration as a biological control agent of exotic Ludwigia spp. in the USA and further testing is not warranted.