Macroscopic and microscopic fungi with insecticidal activity

Agri-food production is affected by various factors, such as insect pests. Inadequate use of pesticides has generated resistance, and some pesticides have been shown to affect human health and the environment. Therefore, alternative control methods have been sought, such as the use of biocontrol with fungi; these organisms have shown activity against insect pests. Thus, this review compiles relevant and important studies that have been carried out over the last four decades. In general, fungi are divided into two large groups, macroscopic and microscopic fungi. In these two groups, possible fungal candidates with activity against insects have been found. They were subdivided into two groups: microscopic entomopathogenic fungi and macroscopic entomopathogenic fungi with basidiomata. In the case of microscopic entomopathogenic fungi, only the main species of these fungi (Metarhizium anisopliae, Beauveria bassiana, and Isaria fumosorosea) have been examined. These fungi present degrees of specificity at the family or closely related species level. For these three fungal species alone, more than 500 species of affected insects have been reported in this and other reviews. Finally, more than 200 species of fungi with basidiomata have been studied for their insecticidal activity. Additionally, possible compounds with insecticidal activity, such as ibotenic acid, beauvericin, ergosterol, and ostreolysin, are described. The studies found in the present review of fungi with insecticidal activity are promising. It was concluded that fungi, their compounds, and the proteins they contain may have a biotechnological application in the control of insect pests.