Abstract:
Central highland is one of the major Cabbage (Brassica oleraca) producing regions in Sri Lanka. Diamondback
Moth (DBM) (Plutella xylostella) is one of the key pests of cabbage that causes a significant yield loss. Farmers
heavily use agro-chemicals to control DBM while ignoring alternative non-chemical eco-friendly pest management
strategies. Therefore, attempts were made to evaluate the combined effectiveness of three physical pest
management strategies to suppress the DBM population in cabbage. Field experiments were carried out at the
Agriculture Research Station, Seetha-Eliya during the 2020 and 2021 Yala cropping seasons. A blinking light,
sprinkler irrigation and insect-proof net were selected as physical DBM control measures. The combined effects of
these strategies were evaluated in comparison with recommended insecticides. The result revealed that the
combined effect of blinking lights, sprinkler irrigation and insect-proof net significantly reduced DBM larval
infestation and damage severity of cabbage with effective yield performance. Blinking lights and insect-proof net
were found to be alternative strategies to manage DMB larval infestation. Routine application of insecticides for
DBM control in cabbage could successfully be replaced with these physical barriers. It was concluded that a
package for DBM management in cabbage comprising of these measures could be introduced for cabbage farmers
in the up-country region in Sri Lanka.