Arthropods Associated with Corn Planted in the Marginal Uplands of Inopacan, Leyte

Abstract

A study was conducted to assess and identify the arthropods associated with corn planted in the marginal uplands of Inopacan, Leyte, using pan trap and sweep net methods, done biweekly during the two cropping periods. Two major groups of arthropods were recorded which included the Arachnids and the insect group, consisting of nine (11) orders of insects represented by 59 insects species and 20 spiders. These arthropods belonged to phytophagous groups (chewing and sucking arthropods); natural enemies (predators and parasitoids) and the inocuous groups or considered “others” (scavengers and saprophagous).

The most abundant insect pest species in corn were the Chrysomelidae and Scarabaeidae beetles, while leafhoppers (Homoptera) were moderately abundant in the crop. The predators were mostly ants (Hymenoptera), the spiders (Arachnids), and coccinellid beetles. The parasitoids included the braconid, ichneumonid, and chalcid wasps. The most abundant non-pest and inocuous species are the Dipterans which are potential hosts or prey of the biotic agents in the corn ecosystem.

TThe abundance of pest species in corn is not yet alarming, which indicates that the pests are not attracted to the crops which were marginal in growth. The natural enemies were also occurring in moderate numbers adequate to suppress abundance of pest species. However, from the results, the corn planted in the marginal upland with chicken dung was observed to have the higher number of insect associations than the other treatments.