Collections of the leaf beetle Henosepilachna elaterii Rossi, 1794 (Protozoa: Microspora) were carried out monthly from July 1988 to June 1991, from melon and cucumber plants in Senegal. Of the 1895 larvae and adults collected and examined, 1223 (64.53%) were infected with Nosema henosepilachnae Toguebaye and Marchand, 1984. The monthly infection prevalence ranged from 51.28% to 87.30%. These observations indicate that the infection due to N. henosepilachnae is prevalent in the natural populations of H. elaterii.

Silkworm larvae infected transovarially with Nosema bombycis were fed with an aqueous suspension of Bavistin (50% carbendazim w/w) at 2 and 3% concentrations. The treatments increased the survival of worms and reduced the pebrine infection in the lot significantly, although complete elimination of infection was not observed. Significant beneficial effects of the treatments at 2 and 3% were also observed with respect to larval, cocoon and cocoon shell weights and cocoon to shell ratio. However, treatments with Bavistin at 4% concentration produced an adverse effect on cocoon characters.

An experimental microspodiosis has been stimulated within Heliothis armigera (Lepidoptera, Noctuidae). The microsporidian used was Nosema manierae, a natural parasite of Chilo zacconius (Lepidoptera, Pyralidae). Nosema manierae causes high mortality in the larvae and the nymphs.