Plantwise Factsheets for Farmers
Managing Banana Corm Weevils with Pseudostem Traps
Recognize the problem
banana corm weevil is a black beetle (1-1.5 cm long), which is found in
debris around banana plants. Female beetles lay eggs singly in small cavities
at the base of the pseudostem of the plant.
Larvae hatching from the eggs are stout and creamy white, legless
grubs which are distinctly curved and swollen in the middle. The head is
reddish-brown with strong mouthparts. Fully-grown grubs are about 12 mm long.
The larvae bore irregular tunnels in the rhizome/corm. Heavy infestation kills
young plants. Heavily infested older plants are easily blown over by wind.
pseudostem trap is simply a fresh 20 – 60 cm longitudinally halved piece of a
banana pseudostem placed on the ground
near a banana mat with its inner side facing the ground. It traps banana corm
weevils in a way that if adult banana weevils are around, they are attracted
to its underside for shelter and egg-laying. However, such a piece of banana
pseudostem can easily be turned over to expose the hiding beetles so that
they are killed mechanically. Also, the eggs which they lay there cannot
complete development to adults since the pseudostem piece is small and dries in
a short time.
Pseudostem traps can be used for
monitoring and managing populations of corm weevils in banana fields.
For monitoring, set 20 traps per
hectare and check them weekly for hiding beetles. If the population / catch
gets to an average of 1 or more beetles per trap per week, control measures
should be employed.
control (mass-trapping), set 100 traps per hectare and check them weekly for
hiding beetles and kill them mechanically if found, e.g. by crushing them with
a stone. Replace the traps when they are dry.
The recommendations in this factsheet are relevant to:
Plantwise Factsheets Library app
Get all of the factsheets and pest management decision guides from this website in an offline format via the Plantwise Factsheets Library app.