Development of a pheromone based management method for cinnamon wood boring moth (Ichneumoniptera cinnamomumi) (Lepidoptera: Sesiidae)

Abstract

In this experiment life cycle, behavior and population dynamics of the wood boring moth, were studied to evaluate the effectiveness of mass trapping through a sex pheromone. Laboratory experiments were conducted at the Cinnamon Research Station and field experiments were done in farmer fields in Galle, Matara and Hambantota districts. Forty five (pheromone loaded water, sticky coated and unloaded control) were established in one and half ha in each district and establishment heights were 30cm, 90cm and 150cm from the ground level. Trap catches were recorded bi-weekly. The females deposit eggs in cracks on the base of cinnamon bushes. Eggs are reddish to dark brown and 1mm length. Incubation period of eggs is about one week. Five larval stages spanning 40-55 days period was identified. The larvae bore into the bark and later tunnel into the heartwood. Larvae are dark pink with a dark brown head. Pupation takes place beneath the bark and last in 35- 40 days. Emerge adult moths survived about 7 days and male to female population found to be 2: 1 ratio. With the increase of air temperature in February to May, population of male moths was reduced significantly. Larvae directly damage to the base. Infestation occurs at sites on the tree where bark has been injured during harvesting. Insect excrement is good indications that tree are infested with wood borer. The plants are weakened by larval tunneling and as a result the mature stems fall. At the severe infestation, emerging shoots are also destroyed with leading to the death of entire bush. Highest number of catches was observed in pheromone loaded yellow sticky delta traps with 90cm and 150cm establishment height from the ground level. In comparison to untreated field, the larval population declined with time in pheromone treated fields. Therefore, sex pheromone could be successfully used to control wood boring moth. Sticky coated delta trap can be used as most attractive trap type with above 90cm trap establishment height.