Metaphycus anneckei and Metaphycus hageni : two discrete species parasitic on black scale, Saissetia oleae

International audienceParasitized black scale, Saissetia oleae, were collected from olives (Olea europaea L.) in Spain and from this material an encyrtid parasitoid was reared that is taxonomically similar to Metaphycus anneckei Guerrieri and Noyes. Differences were noted between the Spanish Metaphycus nr. sp. anneckei and material described as M. anneckei that is resident to California. Although dissimilar in few morphological characters, the ovipositor length and shape of the male genitalia and the antennal club of both sexes can be used to discriminate between M. anneckei resident to California and the Spanish material, which was subsequently named Metaphycus hageni Daane and Caltagirone. To determine if morphological differences correspond to biological differences, reproductive and oviposition behaviours of Californian M. anneckei and Spanish M. hageni were studied. Mating was not observed between individuals of the two types and only male progeny were produced in interspecific pairings. Metaphycus anneckei females deposit eggs through the scale’s ventral side and were never observed to host feed, while M. hageni females oviposit through the scale’s dorsum and frequently host fed. The collective biological evidence agrees with morphological evidence, indicating that M. anneckei and M. hageni are discrete species. Specimens from recent collections in California and Spain were compared with specimens from earlier collections (1910s to 1980s) in Australia, California, Greece, Hawaii, Italy, Israel, Mexico, and South Africa. With the exception of Greek and Spanish material, all specimens examined were M. anneckei. We discuss the significance of this new information with respect to biological control and provide a key to separate these and other closely related black scale parasitoids

Euschistus heros mass rearing technique for the multiplication of Telenomus podisi Técnica de criação massal de Euschistus heros para a multiplicação de Telenomus podisi

The objective of this work was to improve the mass rearing technique of Euschistus heros in laboratory. Nymphs and adults were reared at densities 100, 200, 300 and 400 eggs per Petri dish (9 cm diameter), and at 50, 100, 150 and 200 couples per rearing cages (900 mL), respectively. Survival rate of immature stages and survivorship and reproduction of adults were determinated. Survivorship of nymph to adult was the highest (89%) at density 100 eggs per dish. Adult survivorship was independent of density, and 100 couples per cage were the best to improve quality of the produced progeny. In these conditions, fecundity was 160.8±9.28 eggs per female, and a total of 8,950±456 eggs per cage per month was produced. Two hundred couples per cage showed a negative effect on reproduction, which decreased to 65%. With this technique, a colony of 35 cages with 100 couples per cage yields about 313.3 thousands eggs per month, which is enough to supply the egg parasitoid Telenomus podisi to colonize about 35 ha of soybean field.<br>O objetivo deste trabalho foi melhorar a técnica de criação massal de Euschistus heros em laboratório. Ninfas e adultos foram criados nas densidades de 100, 200, 300 e 400 ovos por placa de Petri (9 cm diâmetro), e 50, 100, 150 e 200 casais por gaiola de criação (900 mL), respectivamente. Foram determinadas a taxa de sobrevivência dos estágios imaturos e a sobrevivência e reprodução de adultos. A sobrevivência das ninfas até o estágio de adulto foi maior (89%) quando criadas em densidade de 100 ovos por placa de Petri. A sobrevivência dos adultos foi independente da densidade, e 100 casais por gaiola de criação foi a melhor densidade encontrada para melhorar a qualidade dos insetos. Nessas condições, a fecundidade das fêmeas foi de 160,8±9,28 ovos por fêmea, e um total de 8.950±456 ovos por gaiola por mês foi produzido. A densidade de 200 casais por gaiola apresentou efeito negativo sobre a reprodução, que decresceu 65%. Com esta técnica, uma colônia de 35 gaiolas com 100 casais por gaiola produz cerca de 313,3 mil ovos por mês, quantidade suficiente para liberar o parasitóide de ovos Telenomus podisi em 35 ha de plantio de soja