Design and evaluation of traps for Idiarthron subquadratum (Orthoptera: Tettigoniidae) with farmer participation in coffee plantations in Chiapas, Mexico.

Three new types of traps designed and made by farmers were evaluated for capture of Idiarthron subquadratum Saussure & Pictet. Bag, sack, and fabric traps were compared with previously used bamboo internode traps. A participatory methodology was used involving farmer interviews and workshops to design and make the traps. Farmer participation was useful for obtaining information on perceptions, knowledge, and control activities of I. subquadratum. The bag trap captured a greater number of individuals than the bamboo and fabric traps, but its captures were similar to those of sack trap; captures were similar in bamboo, sack, and fabric traps. When captured individuals were analyzed by stage of development, no significant differences between types of traps were detected for captured adults. The number of individuals captured in the traps showed a similar trend to that counted in nocturnal sampling. A significant positive relationship was detected between numbers of adults captured and the damage of leaves and fruits. Taylor's Power Law indicates that I. subquadratum individuals were more abundant in some traps than in others. With densities greater than five individuals per trap, a smaller number of bag traps was required to estimate the same population compared with the other types of traps. Sampling procedure that used the bag traps had the lowest cost. This study shows that resource-poor coffee, Coffea arabica L., farmers had accumulated knowledge of I. subquadratum based on unpublished data and experience and that they were capable of applying this knowledge to develop an economical and more suitable technology for their conditions.