DIVERSITY AND ACTIVITY OF INSECT NATURAL ENEMIES OF THE BAGWORM (Lepidoptera: Psychidae) WITHIN AN OIL PALM PLANTATION IN PERAK, MALAYSIA

Abstract

Bagworms (Lepidoptera: Psychidae) are one of the important leaf-eating pests of oil palm in Malaysia and Indonesia. Crop losses, due to the extensive defoliation by a serious bagworm attack are inevitable. The establishment and propagation of the bagworm's parasitoids, depend very much on species of flowering plants as sources of nectar. Cassia cobanensis, was proven suitable due to its attractiveness to most bagworm parasitoids. A study to assess the diversity of bagworm's natural enemies (hymenopterous parasitoids and reduuvid predatory bugs) on the C. cobanensis plant and within the undergrowth of the oil palm planting block was evaluated by sweep net and sticky trap sampling. Environmental parameters such as light intensity, temperature and relative humidity were also recorded during the sampling to determine their possible range of influence towards the activity of the insect natural enemies. The Shannon-Wiener diversity index of insect natural enemies occurring on the C. cobanensis plant was 2.32. Among the dominant parasitoids observed on C. cobanensis plants are chalcids (Brachymeria lugubris and Brachymeria carinata) and braconids (Dolichogenidea metesae and Apanteles aluella), besides the reduuvid predator, Cosmolestes picticeps. In contrast, within the oil palm planting block, the undergrowth within the non-harvesting path only recorded a much lower diversity index of 1.09 and 1.12 each, in a block with C. cobanensis at the roadside and without, respectively. However, C. picticeps was shown to be much more dominant within both oil palm planting blocks, up to two-to threefold , with much lesser numbers of hymenopterous parasitoids (less than five individuals). This indicates the important contribution of C. cobanensis plant towards enriching the diversity of the parasitoids, which are normally not found within the oil palm block, due to much less intense sunlight. In terms of insect activity, they are significantly more active in the moderate or medium light intensities (<8000 fc), medium humidity levels (50%-69%) and medium temperatures (30°C-34°C).

EFFECTIVENESS OF Bacillus thuringiensis AERIAL SPRAYING AGAINST THE BAGWORM, Metisa plana WALKER (Lepidoptera: Psychidae) OUTBREAK IN OIL PALM USING DRONE

“…The planting of beneficial plants attracts beneficial insects which synergises with Bt aerial spraying to degrade the bagworm outbreak (Mazmira et al, 2011). Beneficial insects such as predators and parasitoids were found to be associated with the mortality of bagworms and naturally controlling the bagworm population in oil palm plantation (Basri, 1993;Cheong et al, 2010;Norman and Arshad, 2016). Planters must, therefore,…”

ARTHROPOD FAUNA OF OIL PALM INFLORESCENCE (Elaeis guineensis), WITH NOTES ON THEIR ECOLOGICAL ROLES IN A PLANTATION IN TERENGGANU, MALAYSIA

“…For example, C. morio was found to predate heavily on the larvae of the coconut spike moth (Tirathaba ruvifena), one of the important insect pests of the oil palm tree (Zhong et al, 2016). Other than that, the presence of the parasitic wasp, D. metesea, together with the parasitoid wasp, Buysmania oxymora, suggested natural pest controlling activities at the study area particularly aimed at the other prominent pest of the oil palm tree, the bagworm, Metisa plana (Halim et al, 2017;Kamarudin and Arshad, 2016). Hence maintaining these arthropods in the oil palm plantation could minimise the use of pesticides for pest control, thus supporting sustainable agricultural practices.…”

Mexican creeper, Antigonon leptopus Hook. and Arn : An effective bee forage plant to conserve honey bee

“…To save colonies, apiarists generally resort to feed the colonies with sugar syrup and Antigonon could Mexican creeper not only adds beauty to premises but also helps in sustaining beneficial insect diversity in general and honey bees in particular. The Mexican creeper is also credited as a beneficial plant attractive to parasitoids of oil palm pests and is preferred to be planted around oil palm plantations (Kamarudin and Arshad, 2016).…”