Monitoring of key non-target arthropods on transgenic maize lines containing events DAS-Ǿ15Ǿ7-1 and the combined trait product DAS-Ǿ15Ǿ7-1 X MONǾǾ81Ǿ-6 X MON-ǾǾ6Ǿ3-7:2011 Philippines field study

Issue Date

10-2013

Abstract

Field evaluation of transgenic maize lines containing single event and the combined trait product was conducted in two regulated trial sites in the Philippines, one in Luzon (Cauayan, Isabela) and another in Mindanao (Tampakan, South Cotabato) during the 2011 wet season and 2012 dry season. The hybrids are intended to control the Asian corn borer and other lepidopterous pest of corn. The regulated field trials were done in compliance with the requirements for risk assessment to non-target organisms, particularly arthropods, The effects of these Bt corn types and their isohybrids with and without insecticide treatment on the non-target arthropods were compared. Collection and/or observations of arthropods were done using different sampling methods: sweep net, visual counts, pittfall traps, sticky traps and sugar and protein baiting at 20, 40, 55-60 and 80-85 days after planting. There were 237,973 and 106,426 individuals collected in Isabela and South Cotabato, respectively.These individuals represent 486 and 461 species/morphospecies from the two respective trial sites. They are classified under 18 insect/arthropod orders with 111 families for Isabela and in 17 insect/arthropod orders with 101families for South Cotabato. Based on functional guilds, the greatest proportion of individuals was recorded for non-target herbivores ranging from 40.91 % (Wet Season) to 82.06 % (Dry Season) in Isabela and from 45.75% (Wet Season) to 67.57% (Dry Season) in South Cotabato. These were followed by predators and neutrals. Pollinators were relatively fewer than those in the other guilds. Pollinators, particularly in South Cotabato, became abundant only during pollen shedding. On the hand, the low recovery of parasitoids was probably affected by the sampling techniques used. The diversity of arthropods collected in the confined trial sites in Isabela and South Cotabato is a good indication of the richness of arthropod taxa even in corn fields in tropical regions like the Philippines. The most dominant groups were the lady beetles, various spiders, predatory bugs, ants and staphylinid beetles. Abundance, diversity and guild structure/composition of non-target arthropods (NTAs) did nor differ significantly among treatments. Over-all, data generated from wet and dry season trials in Isabela and South Cotabato, support the earlier results that the single trait Bt corn hybrid and the stacked Bt corn hybrid have no effects on non-target arthropods in the corn ecosystem.

Source or Periodical Title

The Philippine Entomologist

ISSN

0048-3753

Volume

27

Issue

2

Page

213

Document Type

Article

Frequency

semi-annually

Language

English

En – AGROVOC descriptors

ARTHROPODA; MAIZE; TRANSGENIC PLANTS; TRANSGENICS; MONITORING; PHILIPPINES

This document is currently not available here.

Share

COinS