Dispersal ofRhyzopertha dominica(Coleoptera: Bostrichidae) in Different Habitats

Abstract

The lesser grain borer, Rhyzopertha dominica (F.) (Coleoptera: Bostrichidae), a serious pest of stored cereal grains, is widely distributed and has been collected in different habitats in North America, such as those from agricultural and nonagricultural settings. Our objective was to study the dispersal distances and direction of dispersal by R. dominica after external marking using fluorescent powder, releasing marked beetles, and recapturing adults using pheromone traps in distinctively different ecological habitats, wooded sites and open grasslands, for 2 consecutive yr. The recapture rate of marked beetles ranged from 6 to 26% in both sites and was generally higher in the wooded site than the open field site for both years. There was a significant difference in dispersal distances between wooded and open sites. Mean dispersal distances in the wooded site ranged from 337 to 375 m, whereas in the open site, they varied from 261 to 333 m. Trap captures for both marked and feral beetles were related to the ambient temperature such that increase in trap captures occurred with increasing temperature. Significant differences were observed for directional movement of R. dominica in both sites and indicated that most beetles dispersed in the northwest direction. Correlation analyses showed that the relationship between numbers of marked-released-recaptured beetles significantly decreased with increasing trap distances. Understanding dispersal distances and directions provide insight to flight behavior of R. dominica and to the relationship between ecologically diverse breeding habitats. Knowledge of R. dominica habitat ecology outside of grain storage facilities may be useful in designing suitable management tactics to minimize the onset of infestations in grain storages.

Ambrosia Beetle (Coleoptera: Curculionidae: Scolytinae) Captures Using Colored Traps in Southeast Tennessee and South Mississippi

“…In a mark-recapture study, the striped ambrosia beetle, Trypodendron lineatum (Olivier) (Coleoptera: Curculionidae), which is a coniferous forest tree pest in the western United States, only exhibited non-directed flight for distances of 100 m or more, whereas recaptures at 500 m were primarily downwind of the release point (Salom & McLean 1989). Mean dispersal distances of marked lesser grain borers, Rhyzopertha dominica (F.) (Coleoptera: Bostrichidae), were significantly longer in wooded sites as compared with open sites (Mahroof et al 2010). Similarly, T. lineatum was recaptured in significantly higher numbers from baited traps in forested as opposed to open settings, likely due to wind speeds roughly 4 times higher in the open settings (Salom & McLean 1991).…”

Walking stability of Rhyzopertha dominica (Fabricius, 1792) (Coleoptera: Bostrichidae)

“…The beetle R. dominica, although considered a good flyer since field research showed that adults of this Coleoptera dispersed on average up to 375.50 m from the point of release in a wooded environment and 333.97 m from the point of origin in locations without trees (Mahroof et al, 2010), when there are limitations to its movement by air it is required to walk. On flat and smooth surfaces, similar to those of laboratory bioassays, care must be taken since movement of this Coleoptera is highly impaired by factors related to adherence in relation to its body shape, due to the fact of its displaced CG, resulting in imbalance and consequent rollover while walking.…”

More than a pest management tool — 45 years of practical experience with insect pheromones in stored-product and material protection

“…Some very well studied beetles allow for additional interpretations of outdoor trapping data. For instance, outdoor catches of the bostrichid beetle Rhyzopertha dominica in Canada, the USA, and Australia using the beetles aggregation pheromone in pheromone-baited traps revealed that the lesser grain borer may very well breed in natural forests and spread to uninfested grain storage facilities by flying long distances (Cogburn et al 1984, Fields et al 1993, Edde et al 2005, Edde & Phillips 2006a, Edde et al 2006, Toews et al 2006, Daglish et al 2010, Mahroof et al 2010. It was believed that the lesser grain borer is mainly a pest of the warmer regions of the world and would occur at least in Canada only with infested grain imports.…”