Abstract:
In this study, we investigated the pheromones of Gonipterus species 2
(Coleoptera: Curculionidae) and Nudaurelia clarki (Lepidoptera: Saturniidae). These
insects are two South African plantation pests that have caused the forestry industry
tremendous economic losses due to defoliation. The development of pheromonebased
management tools for these pests can ensure sustainable and effective pest
control without detrimental effects to surrounding environments.
Our results showed that Gonipterus sp. 2 produces at least cis- and transverbenol,
which were described as putative pheromone components for G. platensis.
Female headspace samples contained larger concentrations of the same volatiles
than male samples. Furthermore, topical application of Juvenile hormone III does not
induce pheromone production in Gonipterus sp. 2.
The described pheromone of N. cytherea, Z-dec-5-en-1-yl-3-methylbutanoate,
was shown to be effective for trapping N. clarki in KZN. The synthesized pheromone
consisted of four electroantennographically active compounds, and attracted
numerous N. clarki male moths species-specifically. We report on the first instance of
female autodetection in the Saturniidae family, because female N. clarki antennae also
detect the pheromone. The attractiveness of the same pheromone to both N. cytherea
and N. clarki, together with preliminary genetic evidence that shows identical
cytochrome oxidase I sequences between these species, reveal that these two
species might actually be one. Future development of pheromone-based pest
management strategies requires confirmation of the attractiveness of cis- and transverbenol
to Gonipterus sp. 2, and optimizing N. clarki pheromone-based trapping for
use in mass-trapping or mating disruption mechanisms.
