Dr. Jaco
Le Roux hopes to establish the number and identity of
the leafhopper species introduced to Hawaii so he can
assess the threat that it poses to our local flora and
fauna. This research effort includes molecular systematics
and phylogeography of invasive leafhoppers and those
from putative source regions. These data could potentially
also assist in identifying native range regions where
productive biological control agents are likely to be
found, should this prove a viable control option.
“Macrosteles”,
or 'aster leafhoppers' represent a newly introduced insect
pest that has invaded O'ahu watercress crops. They transmit
an aster yellow pythoplasma that has cost the watercress
industry hundreds of thousands of dollars in damage due to
crop losses. Of even greater concern is the possibility that
the leafhoppers in Hawai'i will spread and negatively impact
other agricultural crops. Understanding the invasion history,
e.g. the country of origin, the route of introduction, etc.,
is the first step in initiating efforts to control or eradicate
any invasive species. The taxonomy of the genus Macrosteles
is problematic due to morphological conservatism across different
species, making identification cumbersome at best.