Endophytic Fungi from the Four Staple Crops and Their Secondary Metabolites

Endophytic fungi are present in every plant, and crops are no exception. There are more than 50,000 edible plant species on the planet, but only 15 crops provide 90 percent of the global energy intake, and "the big four"-wheat, rice, maize and potato-are staples for about 5 billion people. Not only do the four staple crops contribute to global food security, but the endophytic fungi within their plant tissues are complex ecosystems that have been under scrutiny. This review presents an outline of the endophytic fungi and their secondary metabolites in four staple crops: wheat, rice, maize and potato. A total of 292 endophytic fungi were identified from the four major crops, with wheat having the highest number of 157 endophytic fungi. Potato endophytic fungi had the highest number of secondary metabolites, totaling 204 compounds, compared with only 23 secondary metabolites from the other three crops containing endophytic fungi. Some of the compounds are those with specific structural and pharmacological activities, which may be beneficial to agrochemistry and medicinal chemistry.