Mating Disruption for Control of <I>Melanotus okinawensis</I> (Coleoptera: Elateridae) with Synthetic Sex Pheromone

Abstract

A mating disruption experiment to control Melanotus okinawensis Ohira (Coleoptera: Elateridae) was conducted at a sugarcane (Saccharum spp.) field and a wild Japanese pampas, Miscanthus sinensis Anderss, grassland on Minami-Daito Island (3,057 ha) from 2001 to 2007. The sugarcane field and the pampas grassland were treated with synthetic sex pheromone that evaporated from a polyethylene tube dispenser. The mean total catches obtained by monitoring traps in the sugarcane fields decreased by 96.1% in 2001 from the previous year on Minami-Daito Island. The mean total trap catches in the treated area further decreased by 74.0% from 2001 until 2007 as cumulative effects. Simultaneously, the number of adults captured by hand decreased from 4.7 per sugarcane field in 2001 to 0.5 in 2007 (89.3% reduction), whereas those captured in the untreated area (Miyagi Island) did not show such a decrease. The mating rates were significantly lower in the females captured in the treated area (14.3-71.4%) than those in the untreated area (96.9-100%). However, the amount of the decrease in the trap catches was relatively small at first (39.6% reduction) in the Japanese pampas grassland on the periphery of the Island. This was probably due to the loss of pheromone substance caused by the strong seasonal wind in the periphery. However, mean total trap catches at the periphery also decreased within several years; significant decreases were detected until 2003, 2006, and 2007. These results indicated that the mating disruption effectively reduced an isolated population of M. okinawensis.

Spatially implicit approaches to understand the manipulation of mating success for insect invasion management

“…N* is the unstable equilibrium point below which populations decline was set to yield a net reproductive potential identical to that of type-L insects assuming that the type-C females can lay eggs every day while the type-L will mate and oviposit just the day after emergence. The type-C emergence period is more protracted [l = 50 and r = 12 in ND (l, r)] compared to those of type-L considering that the prevalence of O. communa or M. tamusyensis continues for about a month (Watanabe 2000;Arakaki et al 2008). Females and males can mate as long as they survive though they can mate only once per day as is known for many Coleopteran species (Simmons 2001).…”