The multifunctionality of the fungus Metarhizium spp. and its use in Brazilian agriculture

The genus Metarhizium is extremely diverse, with 66 species described worldwide, among which 60 are entomopathogenic. Despite the diversity of 14 species found in Brazil, Metarhizium anisopliae is the fungal species with the highest number of registered products. It is an active ingredient in 100 products, while Metarhizium rileyi is in only four. This was the first on-farm-produced fungus in Brazil by sugarcane mills in the 1960s to control sugarcane leafhoppers. Currently, more than 50 on-farm biofactories produce this fungus for application on more than 2 million hectares, making it the largest microbial control program in the world. Brazilian producers have often used fungi in a mixture with synthetic chemical insecticides, aiming at shock action by the chemical and the residual action of the biological (55% of producers use biocontrol agents in a mixture with chemicals for pest control). The impact of M. anisopliae as a mycoinsecticide has recently been enhanced by the discovery that it colonizes plant roots, which can exploit its ability to control disease, promote plant growth, and as a bioprotectant. This systematic review demonstrates that Metarhizium is a versatile fungus adaptable to diverse environments and has remarkable genetic, physiological, and ecological flexibility, making it the most widely used fungus for pest control. In addition, the prospects for future studies and increasing the use of this fungus to mitigate the damage caused by pests in Brazilian crops are discussed.