The diamondback moth (Plutella xylostella
) originated in the Mediterranean region of Europe but is moth now found worldwide. It was first observed in North America in 1854, in Illinois, and it spread throughout the continent by 1900. The diamondback moth has a short life cycle (14 days at 25°C) and is highly fecund. Although it is a poor and low flyer, it is found in locations where it does not overwinter (e.g. Northern Canada), as it can travel by wind for long distances. Plutella xylostella
overwinters as an adult moth, and on warm days in temperate climates is frequently seen flying in winter. It is one of the most important pests of cruciferous crops (family Brassicaceae) in the world and will usually only feed on plants that produce glucosinolates. However, not all of these plants are equally useful as hosts to the moth; there has been some discussion of using wintercress (Barbarea
species) as a buffer plant around agricultural fields as diamondback moths are highly attracted to that plant but their eggs fail to survive when oviposited on it. First instar larvae feed by leaf mining; subsequent instars feed mostly on the underside of the leaf, and then usually pupate there, also. Historically this pest was controlled through the use of chemical insecticides, however the diamondback moth has developed widespread resistance to most insecticides, and also to biological control methods using Bacillus thuringiensis
(Bt). The parasitic braconid wasp Cotesia plutellae
shows promise in controlling P. xylostella
; it has been reared in laboratories and released as part of Integrated Pest Management programs in several countries.
; Wikipedia 2011