Some populations of
T. absoluta have developed
resistance to
organophosphate and
pyrethroid pesticides. Newer compounds such as
spinosad,
imidacloprid, and
Bacillus thuringiensis have demonstrated some efficacy in controlling European outbreaks of this moth. Insecticide costs have increased rapidly, and even that has not always produced good results, due to high quantity application of insecticides that are not especially effective against
T. absoluta. As a result, new registrations have been obtained specifically for this pest starting in 2009. Between 2009 and 2011 there was a dramatic increase in authorized
APIs and
MoAs in Spain and Tunisia for this reason.
Bacillus thuringiensis,|leftThe sex pheromone for
T. absoluta has been identified by researchers at Cornell University and has been found to be highly attractive to male moths. Pheromone lures are used extensively throughout Europe, South America, North Africa and the Middle East for the monitoring and mass-trapping of
T. absoluta. The use of pheromone products in combination with a yellow delta trap has been recorded in South Africa. This concept is used to monitor populations of
T. absoluta in tomato orchards. Also the use of electric mosquito traps give good results.
Insecticide resistance History and genetics Organophosphate and pyrethroid resistance developed in
Chile, then in
Brazil and (as noted above)
Argentina. (The use of
chlorantraniliprole for
T. absoluta has also resulted in resistance in
B. tabaci, even though it is not used against that species, merely because they co-occur on tomato. This is expected to make
cyantraniliprole unusable if needed on
B. tabaci, in the same area.)
Voltage-dependent sodium channel blocker resistance Resistance to
indoxacarb (IRAC group 22A) has appeared due to the mutations F1845Y and V1848I, but is not yet reported for another
voltage-dependent sodium channel blocker,
metafumizone (22B). (These two mutations, as with the diamides above, have
P. xylostella analogues, but in
this case these analogues
are known to be effective against
both indoxacarb and metafumizone.)
Nicotinic acetylcholine receptor channel blocker resistance Cartap, a
nicotinic acetylcholine receptor channel blocker (IRAC group 14), began to show low to moderate efficacy decline in South America starting in 2000, and increasing through at least 2016. Some of this is due to elevated cytochrome P450 activity (see
below) possibly as part of
demethylation and
sulfoxidation detoxification, while less is thought to be due to
esterases and
glutathione S-transferases. (The use of
cartap for
T. absoluta has also resulted in resistance in
B. tabaci, even though it is not used on that species, merely because they co-occur on tomato.)
Cytochrome P450 and resistance Cytochrome P450s are used to resist: •
cartap, :*possibly as part of
demethylation and
sulfoxidation detoxification, • possibly also
abamectin :*along with resistance due to higher esterase activity, • but not
pyrethroids, :*because although important in other insects, :*they are of limited usefulness in this case for reasons still unknown, but overall, specific information is still lacking connecting which particular P450s and which particular resistances. ==References==