Stability of Metarhizium ac ridum Based Biopesticide in Operational Conditions in Senegal

Abstract

Grasshoppers and locusts are important pests in the Sahel zone with a big economic and environmental impact. The move towards biological control methods represents an important option to mitigate environmental impact linked with the use of insecticides for their control.Metarhiziumacridum, a locust pathogenic fungus that gave excellent test results in controlling grasshoppers, was further developed as biopesticide. The stability of the manufactured biopesticide in operational conditions was tested. In the present study, the germination of spores and mycelial growth of M. acridum were higher at 28 °C and 33 °C. Higher temperatures led to a significant decrease of these biological parameters. The sporulation of M. acridum is abundant at 28°C and 33 °C but was completely inhibited at 37 °C. Furthermore, M. acridum based biopesticide showed a good infection rate for the dry spores formulation for 3 months of storage in all test sites. In the oil formulation in contrast, infectivity rate dropped quickly to a very low level after one month storage in the inland sites and remained good in Dakar. High temperatures and low moisture, away from the coast were speculated to be the reasons.