Thesis (BS Biology) -- University of the Philippines Mindanao, 2001

This study on the biological attributes, parasitization rate and relative abundance of Trichomma cnaphalocrosis (U.) a larval-pupal parasitoid of the Asian corn borer was conducted to describe its external morphology, biological attributes, parasitization rates and its relative abundance. The host insects were collected in Kabacan, Cotabato, Tupi and Tampakan, South Cotabato, Manolo Fortich, Bukidnon and in bago Oshiro, Davao City from june to November 2000. The parasitoids were studied b rearing them separately under laboratory conditions. The observations on the external morphology of T. cnaphalocrosis was conducted by measurements and examination under the stereoscope and photographs. Results showed that the female T. cnaphalocrosis is largr than the male. Its antenna is filiform, mandubulate mouthpart, and thorax is fused with the abdomen. Its forewings have distinct taxonomic character of two-recurrent vein and hindwings are smaller in size. Both are covered with numerous setae. The legs are 5-segmented and the trochanter is 2-segmented which is also a distinct taxonomic character. The abdomen consists of eight segments; male possess claspers and female has ovipositor. High parasitization rate of 31% was observed in Manolo Fortich, Bukidnon and in November. Relative abundance of the T. cnaphalocrosis was also high (0.25/corn borer, 0.16/corn plant and 0.95/sq.m.) in Bago Oshiro, Davao City. Based on these results the T. cnaphalocrosis has the potentials of becoming a biological control agent (BCA) against Asian corn borer