Biologi Reproduksi Brachymeria Lasus Walker (Hymenoptera: Chalcididae) pada Ulat Penggulung Daun Pisang Erionota Thrax Linnaeus (Lepidoptera:Hesperiidae)

Abstract

The objective of this research was to obtain information on the life span and some reproduction characteristics of Brachymeria lasus adults, including number of offsprings produced by a single parasitoid, sex ratio, and the most suitable host pupal age for parasitoid development. The research was carried out in The Laboratory of Biological Control, Department of Plant Protection, Bogor Agricultural University. Parasitoids B. lasus were obtained by collecting pupae of Erionota thrax parasitized by B. lasus from the field, and then were kept in plastic containers in the laboratory. Rearing of B. lasus was conducted by putting a copulated female of parasitoid in a test tube provided with fresh pupae of E. thrax to be parasitized, and fed with 10% honey solution. Effect of food and host (no food no host, with water no host, with 10% honey no host, and with 10% honey with host) on the life span of parasitoid adults was observed. To observe the total number of offsprings, a copulated female was provided with fresh host pupae (one pupa or two daily as needed) every day until the parasitoid died. To find the suitable host pupal ages for parasitoid development, a different age of host i. e. prepupae, 1, 2, 3, 4, 5, and 6 day-old pupae, each was exposed to a different copulated parasitoid female for 18 hours. Effect of three different sizes of host pupae (small, medium, and large) on the parasitoid offspring production was also observed. Females of B. lasus provided with 10% honey solution as food with or without pupae as host could live longer (12-17 days and 10-13 days, respectively) compared to those without food or fed with water only which could live for only 3 days. Number of offsprings produced by a female of B. lasus ranged 71-126, with the average of 98.2. Parasitoid B. lasus could develop successfully in 1-3 day-old host pupae. The parasitoid could parasitize prepupae and pupae older than 5 days but the parasitoids could not complete their develpoment. The host pupal size affected the number and the sex ratio of parasitoids emerging from a single host pupae.