Serangga20(1): 43-53 ISSN 1394-5130 © 2015, Centre for Insects Systematic, Universiti Kebangsaan Malaysia BUNCH MOTH, TIRATHABA RUFIVENA (LEPIDOPTERA: PYRALIDAE) INFESTATION CENSUS FROM OIL PALM PLANTATION ON PEAT SOIL IN SARAWAK Zulkefli Masijan, Norman Kamarudin, Ramle Moslim, Alindra Gerald Sintik, Siti Nurul Hidayah Ahmad and Siti Ramlah Ahmad Ali Biological Research Division, Malaysian Palm Oil Board, No. 6, Persiaran Institusi, Bandar Baru Bangi, 43000 Kajang, Selangor Corresponding email: zulmas@mpob.gov.my ABSTRACT Tirathaba rufivena is the major pest in oil palm plantation planted in peat soil in Sarawak. High infestation was reported in Miri, Mukah and Sibu. Censuses on the infestation of T. rufivena were conducted at three different locations, i.e. in Miri (young palm), Mukah (mature palm) and Sibu (ablation samples). Samples for census were taken from infested bunches, female and male inflorescences. The census was done by chopping the bunches and the female inflorescences while for the male inflorescences, the bottom of spikelets were cut to determine the number of live larvae and pupae. The census