English name: Old World (African) Bollworm
Nordic names: Ugle (DK), Pestfagerfly (NO)
Major host plants
Primarily ornamental plants and flowers. Economically important hosts include cotton, tobacco, tomato, potato, maize, flax, soyabean, Sorghum, lucerne, Phaseolus, chickpea, other Fabaceae, a number of fruits (Prunus, Citrus), and forest trees.
On ornamentals: it mainly damages the flowers. Larvae bore into buds and flowers, feed on the internal contents.
On tomatoes: young fruits are invaded and fall. Secondary infections by other organisms lead to rotting.
On maize: cobs are invaded and developing grain is consumed. Secondary bacterial infections are common.
Widely spread in Asia, Africa, Australia, New Zealand and Europe. Absent/eradicated in many Northern European countries.
A map can be downloaded from EPPO's website. See instructions here.
Each female lays 500 - 3000 eggs, which hatch in 3 to 5 days. The number of larval instars and the duration of the larval period vary depending on the host plant and the temperature. Larval and pupal periods last 17 to 35 and 17 to 20 days, respectively. Pupation occurs in the ground. Overwintering takes place in the pupal stage. Diapause occurs and it depends on temperature and food availability. Adult moths emerge in late spring and feed on nectar. The life cycle is completed in 25 to 60 days and it produces 2 to 6 generations a year, depending on the temperature.
Adults can migrate over long distances, borne by wind. Movement in international trade is mainly on ornamental plants and on cut flowers; also in cotton bolls and in tomato fruits.
Detection and inspection
The feeding larvae can be seen on the surface of plants but they are often hidden inside plant organs (flowers, fruits etc.). Bore holes may be visible, but otherwise it is necessary to cut open the plant organs to detect the pest. In North and South America, the pathogen can be easily mixed up with H. zea, only experts can distinguish these two species.
Pest status and importance
H. armigera may cause serious losses throughout its host range, in particular to cotton, tomatoes and maize. There is a risk of introduction into glasshouse crops in northern Europe.
Source of information
See further information here:
Author: Jorma Rautapää
Editor: Elise T. Yamamoto Buch