Investigation into the microbiology of two soil types (fresh water and agricultural soil) for metamorphosing larvae (Bunaea alcinoe) revealed the presence of the three species of bacteria namely, Bacillus cereus, Pseudomonas aeruginosa, Micrococcus luteus, and three species of moulds, Mucor spp., Penicillium spp. and Aspergillus niger. Isolation, characterization and identification were done according to standard methods and reference manuals. Total heterotrophicbacterial counts were 2.4x108 cfu/g and 1.1x107 cfu/g for fresh water sand and agricultural soil respectively. Total heterotrophic mould counts from the sand and the agricultural soil were 1.6x103 cfu/g and 1.2x105 cfu/g respectively. Total mould counts from Gari extract (GEA) was slightly higher than in the conventional medium (SDA). Strains of Bacillus cereus and Pseudomonas aeruginosa produce enzymes, including chitinase and phospholipase which damage exoskeleton and kill insects directly or indirectly. Micrococcus spp. are saprophytic or parasitic, but not pathogenic. Malformation of moth exoskeleton and subsequent emergence from the fresh water sand was mostly by high number of B. cereus. Certain Penicillium species produce antibiotics which check harmful bacteria level in the agricultural soil. Further more, the activities of the mould in the agricultural soil help to protect the metamorphosing insect larvae.
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