Density of Diachasmimorpha longicaudata (Ashmead) and host Ceratitis capitata (Wied) larvae for the increase of parasitoid female production

Densidade de Diachasmimorpha longicaudata (Ashmead) e do hospedeiro Ceratitis capitata (Wied) no incremento da produção de fêmeas do parasitoide

Carlos Gustavo da Cruz Clarice Diniz Alvarenga Patricia Cristina do Carmo Oliveira Edileuza dos Reis Souza Conceição Zenobia Cardoso dos Santos Teresinha Augusta Giustolin Maria das Dores da Cruz Souza About the authors

ABSTRACT:

The objective of the present study was to evaluate the ratio of Ceratitis capitata larvae/female of Diachasmimorpha longicaudata that results in the increase of parasitism and the production of females in the progeny. We used 8-day-old copulated D. longicaudata females with oviposition parasite experience and third instar larvae of C. capitata from rearing stock maintained at the Laboratory of Biological Control of Universidade Estadual de Montes Claros (Unimontes). Five densities of C. capitata larvae (10, 20, 30, 40, and 50) were offered to parasitoid females that were at five different densities (1, 2, 5, 10, and 15). The larvae were exposed to the parasitoid females by means of “parasitism units” in adapted cages for 1 hour. Sex ratio, percentage of parasitism, and pupal mortality were evaluated. Both host larval density and female parasite density influenced parasitism, female progeny production, and pupal mortality. Higher female production was observed in the progeny in ratios of 1:1 and 2:1 (larvae/females). Ratios above 1:2 reduced the sex ratio, and ratios below 1:1 caused high pupal mortality rates. The females had higher parasitism activity when they were in groups dividing the same space. Equal ratios of Ceratitis capitata larvae and parasitoid females resulted in improved efficiency in progeny females.

KEYWORDS:
biological control; sex ratio; fruit flies; parasitism

Instituto Biológico Av. Conselheiro Rodrigues Alves, 1252 - Vila Mariana - São Paulo - SP, 04014-002 - São Paulo - SP - Brazil
E-mail: arquivos@biologico.sp.gov.br