Notes on the distribution and biology of Pediobius furvus (Gah.) (Hym., Eulophidae), a parasite of graminaceous stem-borers

Pediobius furvus (Gah.) (Eulophidae) is a parasite of the pupae of Pyralid and Noctuid stem-borers on graminaceous crops in Africa between 17°N and 17°S. It co-exists with the other pupal parasites Dentichasmias busseolae Heinr. and Procerochasmias nigromaculatus (Cam.) (Ichneumonidae) and Hyperchalcidia soudanensis Steffan (Chalcididae), but it is more abundant below 4000 ft where P. nigromaculatus does not occur. Mating follows a courtship dance, and oviposition occurs in any part of the host pupa. The life-cycle is completed in 18–20 days at 30°C, and up to several hundred adults may emerge from a single host pupa, the most suitable pupae being 2–3 days old at the time of oviposition. Longevity was improved when sucrose was provided as food. Host pupae outside the stem were parasitised, but puparia of Diptera and cocoons of Apanteles sesamiae Cam. (Braconidae) were not parasitised in the laboratory. Pupae formed inside cocoons were not attacked. Pediobius furvus has become established in Madagascar on Sesamia calamistis Hmps, and is considered promising for biological control of graminaceous stem-borers in other countries.

Notes on Apanteles sesamiae, Cam., a Parasite of the Maize Stalk-borer (Busseola fusca, Fuller) in South Africa

1. Apanteles sesamiae, Cam., is the only parasite of Busseola fusca, Fuller, which is of importance in the Eastern Transvaal.2. The adult is described, and the morphology of the last stage larva of the parasite is discussed in detail.3. The biology and bionomics of the species are dealt with, and the effect of parasitism on the host is described.4. The extent of natural parasitism and the rapidity of increase in the field shows that A. sesamiae is an effective parasite of the Maize Stalk-borer in South Africa.5. The results of cold storage experiments are given and the methods of shipping parasite material are described. It was found impracticable to ship cocoons, but successful consignments of parasitised borer larvae were sent to Canada.