Microcharops anticarsiae (Hym.: Ichneumonidae) parasitoid ofAnticarsia gemmatalis (Lep.: Noctuidae): Host age preference, sex ratio effects and functional response

Abstract

The endoparasite, Microcharops anticarsiae Gupta, is one of the natural control agents of Anticarsia gemmatalis H/.ibner. The effects of host age on the levels of parasitisation and the sex ratio of the subsequent progeny, together with the functional response of M. anticarsiae at 6 different host densities, were evaluated experimentally. In choice experiments involving two or four consecutive instars, female parasitoids showed no preference for host larvae of a particular age. The sex ratio of the parasitoids was affected by the host instar in which they developed (G3dr = 18.21, p < .001). Parasitoid sex ratio was most skewed towards females in parasitoid larvae that developed in 4th instar hosts.A type II functional response was exhibited by the female parasitoid in response to host density.Information on the sex ratio, indicated the best host instar to parasitize to produce an optimum female: male sex ratio, while the functional response indicated the average rate (38.0 __. 7.5) of parasitism per female. This information is important for mass-rearing of M. anticarsiae, for biological control programs against A. gemmatalis.

Effects of host pupal age on host preference and host suitability in Brachymeria lasus(Walker)(Hymenoptera: Chalcididae).

“…These data showed that there were no cues which allowed the female wasps to discriminate hosts of different ages from a distance. Other parasitoid species, i.e., Microcharophis anticarsiae, a larval parasitoid of Anticarsia gemmatalis (Patel and Habib, 1993) and Microplitis croceipes, a larval parasitoid of soybean and corn pests (Harrison et al, 1993) also showed no preference for hosts of particular age and no host-age effect on host suitability.…”

Development of Microcharops anticarsiae Gupta (Hym., Ichneumonidae), an endoparasitoid of the velvetbean caterpillar, Anticarsia gemmatalis (Lep., Noctuidae) and morphology of its immature stages

“…Among entomophagous wasps, species belonging to two genera, Glyptapanteles (Braconidae) and Microcharops (Ichneumonidae) are usually found acting all over the soybean season (PATEL, 1991). Of all the parasitoid species, attacking A. gernmatalis, Microcharops anticarsiae Gupta is the most frequent in all soybeanproducing states (CORREA, 1979;PATEL, 1991).…”

“…Among entomophagous wasps, species belonging to two genera, Glyptapanteles (Braconidae) and Microcharops (Ichneumonidae) are usually found acting all over the soybean season (PATEL, 1991). Of all the parasitoid species, attacking A. gernmatalis, Microcharops anticarsiae Gupta is the most frequent in all soybeanproducing states (CORREA, 1979;PATEL, 1991). It is a naturally dominant and efficient controlling agent of A. gemmatalis and also parasitizes other soybean lepidopterous pests: Pseudoplusia includens, Hedylepta indicata (PATEL, 1991) and Spodoptera latifacia (CORREA, 1979).…”

“…Of all the parasitoid species, attacking A. gernmatalis, Microcharops anticarsiae Gupta is the most frequent in all soybeanproducing states (CORREA, 1979;PATEL, 1991). It is a naturally dominant and efficient controlling agent of A. gemmatalis and also parasitizes other soybean lepidopterous pests: Pseudoplusia includens, Hedylepta indicata (PATEL, 1991) and Spodoptera latifacia (CORREA, 1979). In south and southeastern Brazil M .…”

“…anticarsiae presented the highest rates of parasitism in relation to any other parasitoid species. In such cases, the maximum level of natural parasitism reached 71% among the velvetbean caterpillars (CORREA, 1979;PATEL, 1991). PATEL (1991) suggested that this species should be Considered as a promising candidate for the IPM (Integrated Pest Management) or the Biological control programmes, for the control of soybean lepidopterous Pests.…”