Tip
Top Bio-Control Technical Bulletin
Diglyphus
isea
Parasitic Wasp
Target Pest:
Several species of Leafminer
pests (Diptera: Agromyzidae) in
the genus Liriomyza, including
L. trifolii, L. huidobrensis, and
L. sativae. Regularly used in greenhouse
situations growing ornamentals
and vegetables.
Description:
A parasitic wasp that attacks many species
of Leafminer pests. The Adult wasps are metallic green
and black, 2 - 3 mm in length. Females are larger than
males. Sex ratio is 50/50. Diglyphus females will track
down and sting leafminer larvae in the 2nd an 3rd instar
laying an egg inside the mine. The eggs will hatch
and the larvae will feed on the leafminer and then
pupate in the leaf mine. Diglyphus larvae are very
difficult to locate. However, inspecting leaves by
putting a
light behind the leaf can easily identify the black
and green pupae. Diglyphus will kill a large number
of leafminer's for host feeding. The leafminer pest
have only 3 instar's of development and develop quickly,
in greenhouse conditions. Depending on the conditions,
there may be only 1 day between instar developments.
Product Information:
Diglyphus is a parasitic wasp and is shipped
in bottles of 250 adult parasites.
Release Rates:
Once leafminer-feeding marks are present, releases should
be planned. It is best to release the diglyphus when the first 2nd
instar leafminer larvae are found. Approximately 1 diglyphus should
be released per 10 sq. ft., weekly for several weeks since the leafminer
pest has a short period of venerability to the Diglyphus wasp. Introduce
the beneficial as soon as possible after receipt, best if at the
evening hours. Simply open the container - walk through the area
and allow the wasps to fly out of container.
Lifespan:
After an egg is laid, an adult Diglyphus will emerge from
the leaf in about 3 weeks.
Strategic Considerations:
Many pesticides will
have a negative effect on the development of Diglyphus. Avoid the
use of systemic insecticides or pesticides with long residual action.