New record of Tetrastichus howardi (Olliff) as a parasitoid of Diatraea saccharalis (Fabr.) on maize

Abstract

NoteRESUMO: Diatraea saccharalis (Fabr.) (Lepidoptera: Pyralidae) passa a maior parte de seu ciclo biológico no interior do colmo da planta hospedeira, onde fica protegida contra a ação dos métodos convencionais de controle. O controle biológico tem sido considerado uma alternativa viável para o controle desta praga em cana-de-açúcar (Saccharum officinarum L.) e milho (Zea mays L.), dois hospedeiros preferenciais. Este trabalho relata a ocorrência no Brasil de Tetrastichus howardi (Olliff) (Hymenoptera, Chalcidoidea: Eulophidae) parasitando pupas de D. saccharalis em colmos de plantas de milho. Ele também inclui dados preliminares sobre alguns aspectos biológicos do parasitóide. Uma fêmea de T. howardi foi capaz de produzir até 66 descendentes em uma única pupa do hospedeiro e, aparentemente, não faz distinção entre diferentes idades da pupa. O ciclo de vida do parasitóide foi ao redor de 25,5 dias. A presença do parasitóide no Brasil abre uma nova perspectiva sobre a supressão da broca da cana, considerando os resultados promissores já obtidos em países asiáticos. O inseto é bem adaptado à condição de laboratório, podendo ser produzido em grande número, tornando assim, uma opção adicional para o manejo integrado nas culturas onde D. saccharalis é praga chave, tais como a canade-açúcar, milho e sorgo (Sorghum

Parasitism and biological aspects of Tetrastichus howardi (Hymenoptera: Eulophidae) on Erinnyis ello (Lepidoptera: Sphingidae) pupae

“…The difference in the age of pupae used in the bioassay can be attributed to this result, because they were obtained from the field. Pupae of E. ello parasitized by T. howardi females were probably younger than those not-parasitized, because it was observed that this parasitoid prefers newly emerged pupae (MOORE & KFIR, 1995;PRASAD et al, 2007;CRUZ et al, 2011). Parasitism obtained in this experiment can be increased if the natural enemy is reared for several generations on the E. ello pupae.The lowest variation on duration of the cycle (egg-adult) of T. howardi on E. ello indicates that host pupae are suitable for the development of this parasitoid.…”

“…The presence of the parasitoid T. howardi was recorded in the insect pupae of the families Crambidae, Noctuidae and Plutellidae (MOORE & KFIR, 1995;CRUZ et al, 2011;VARGAS et al, 2011) and could be used to effectively control the lepidopteran pests. Thus, study the ability of T. howardi females to parasitize and develop on E. ello pupae may contribute to the rearing of this natural enemy, as well as to generate opportunities for studying the potential of this parasitoid in controlling of E. ello on cassava crop.…”

Parasitism of Helicoverpa armigera pupae (Lepidoptera: Noctuidae) by Tetrastichus howardi and Trichospilus diatraeae (Hymenoptera: Eulophidae)

“…In Brazil, Tetrastichus howardi has been recorded as parasitizing the pupae of Diatraea saccharalis (Lepidoptera: Crambidae) in sugarcane (VARGAS et al, 2011) and in corn (CRUZ et al, 2011) and pupae of Plutella xylostella in cabbage (SILVA-TORRES et al, 2010). Moreover, studies have demonstrated the ability of this natural enemy to parasitize and develop in the caterpillar stage of D. saccharalis (VARGAS et al, 2011).…”

“…It is important to note, however, that each D. saccharalis pupa was exposed to seven parasitoid females in the earlier study, while each H. armigera pupa was exposed to 15 parasitoid females in the present experiment. In a study carried out by Cruz et al (2011), a single Tetrastichus howardi female was able to produce up to 66 offspring per pupa in D. saccharalis. Thus, the production of offspring can increase in proportion to the density of parasitoids per pupa and the size of female parasitoid hosts.…”

Biological aspects of Eriopis connexa (Germar) (Coleoptera: Coccinellidae) fed on different insect pests of maize (Zea mays L.) and sorghum [Sorghum bicolor L. (Moench.)]

“…Demand for maize, Zea mays L. and sorghum, Sorghum bicolor (L.) Moench (Poales: Poaceae) has increased their cultivated area and, consequently, problems with insect pests in these crops (Sertkaya et al, 2004;Figueiredo et al, 2006a, b;Cruz et al, 2011).…”