Relationship between number of ovipositions of Cotesia flavipes (Cam.) and number of descendants emerged from its host Diatraea saccharalis (Fabr.)

Abstract

(Cam.) foram introduzidas, individualmente, em placas de Petri contendo uma larva de seu hospedeiro Diatraea saccharalis (Fabr.). Permitiu-se que cada fêmea de C. flavipes realizasse posturas uma ou duas vezes em uma mesma larva. O período de emergência das larvas e dos adultos, a razão sexual, o número de larvas e pupas inviáveis e a longevidade dos adultos de C. flavipes registrados nas duas condições experimentais (uma ou duas posturas) foram comparados. Os resultados revelaram que duas oviposições sucessivas no hospedeiro não alteraram a razão sexual na descendência, mas aumentaram o número de parasitóides e também o número de larvas e pupas inviáveis.PALAVRAS-CHAVE: Insecta, parasitóide, superparasitismo, razão sexual, viabilidade.ABSTRACT -Females of Cotesia flavipes (Cam.) were individually introduced into Petri dishes containing one larva of its host Diatraea saccharalis (Fabr.). Each C. flavipes female was allowed to oviposit once or twice in the same larva. Time of emergence of larvae and adults, sex-ratio, number of non-viable larvae and pupae, and longevity of adults of C. flavipes were recorded. Data revealed that two successive ovipositions in the host did not affect sex-ratio, but increased number of parasitoids and number of non-viable larvae and pupae.KEY WORDS: Insecta, parasitoid, superparasitism, sex-ratio, viability.dependent upon host density and having adaptive value (van Dyken & Waage 1987, Hailemichael et al. 1994. Competition among offspring as a result of superparasitism or multiparasitism may occur in relation to available food. In this case, the resultant adults may have their fitness reduced (Hofsvang 1990). This selection of a host by a parasitoid is ba-The success of a host-parasitoid relationship depends upon factors such as habitat location, searching, selection and parasitoid capacity to regulate the host physiologically (Doutt 1959, Vinson & Iwantsch 1980, Stoltz & Guzo 1986, Lawrence & Akin 1990. Multiple ovipositions (superparasitism) does occur among parasitoids, with this behavior being Yamauchi et al. 88sed on the age or instar of the host and a possible perception of equilibrium between amount and quality of food supply for its progeny (Vinson & Iwantsch 1980, Sato 1980, Gobbi & Cunha 1983, Hopper& King 1984, Hagley & Barber 1986, Hebert & Cloutier 1990.The sugar-cane borer, Diatraea saccharalis (Fabr.), is a key pest of sugar-cane in the Americas (Gilford & Mann 1967, Alam et al. 1971, Galichet 1971, Cueva et al. 1980, Gálio 1980, Macedo et al. 1993.Damage occurs by mechanical action as the borer builds internal galleries, causing apical bud death and consequent lateral budding, weight loss, atrophy, and contamination by yeasts that cause red rottenness. Because of the simultaneous presence of all developmental stages of the pest throughout the year and the impossibility of using insecticides to control this borer, a biological control program through releases of the parasitoid Cotesia flavipes (Cam.) was established in Brazil, resulting in substantial reduction...

Effects of dietary palm oil on nutritional indices of Diatraea saccharalis (Lepidoptera: Crambidae) for Cotesia flavipes (Hymenoptera: Braconidae) production

“…The number of unviable cocoons in the control (n = 152) and 1% palm oil (n = 166) were similar, as were those in 0.25% (n = 50) and 0.50% (n = 55). Successive oviposition in the same host increased both the number of viable and unviable cocoons due to food competition (Yamauchi, Gobbi, Chaud-Neto, & Campos-Farinha, 1997). However, in our study, the treatment with the largest production of cocoons was also the lowest of those unviable, indicating that the supplementation provided a good source of nutrients.…”

Efeito de Extratos Aquosos de Azadirachta indica na Sobrevivência de Diatraea saccharalis e do Parasitóide Cotesia flavipes

“…Diante de todos estes aspectos e devido à importância do setor sucroalcooleiro para o agronegócio brasileiro e mundial, diversos trabalhos têm sido conduzidos com objetivo de determinar os danos econômicos desta praga à cultura (LOURENÇÃO et al, 1982;LANDELL et al, 1995;ARAÚJO, 2000;SOUZA et al, 2008). Como alternativa viável de manejo desta importante praga destaca-se o controle biológico BOTELHO, 1988, YAMAUCHI et al 1997, BOTELHO et al 1999.…”

Spatial and temporal population interactions between the parasitoids Cotesia flavipes and Tachinidae flies: considerations on the adverse effects of biological control practice

“…However, this parasitoid has not been efficient in some cases, and new natural enemies have been proposed, such as Trichogramma galloi (Zucchi, 1988) (Hym., Trichogrammatidae) ( Botelho et al., 1999). More details concerning the biology of the species involved can be found elsewhere ( de Almeida et al., 1986; Gallo et al., 1988; Yamauchi et al., 1997; Botelho et al., 1999).…”