Have you ever suffered from the predations of an Indiana meal
moth grub? Probably not but your cornflakes may well have done
so, and this pest is only one of many assorted pests attempting
to steal our food from the supermarket shelves. It is a costly
problem for warehouses and retailers as the female can lay about
300 eggs a week and previously, chemical fumigants have been
used to control the situation. Now however, scientists at the US
Agricultural Research Service at Manhattan in Kansas have found
a couple of allies. These are in the form of a couple of tiny wasps.
One of them, Trichogramma delon is about half a millimeter in
length but is able to find, zero in on and sting to death the moth
eggs. The wasps worked best when the researchers released
them in fairly simple environments, where moth eggs had been
placed on shelves or on top of product packaging. Even better
results are obtained when T.delon is teamed with another midget
of the genus Habrobracon. According to the researchers,
Trichogramma goes after the moth eggs before they can develop
into damaging larvae. Habrobracon finishes the job by killing
any larvae that develop from eggs that Trichogramma may have
missed. The wasps are readily available as they have been used
for many years by cotton growers and other farmers to control
pests in the field.
So in future, if you hear what you think may be a mosquito
whining past your ear in the supermarket, don't swat it. It could
be the duty patrol winging by!

Source: Apis-UK June 2005.