Nematicidal and insecticidal activity of ethyl acetate extracts from culture filtrates of Arabidopsis thaliana fungal endophytes

Endophytic fungi, which live inside plant tissues without causing symptoms of disease, produce a variety of bioactive secondary metabolites. These metabolites have applications in biopesticide development, providing eco-friendly alternatives to conventional plant protection products (PPPs). This study explores the nematicidal and insecticidal properties of ethyl acetate (EtOAc) extracts from endophytic fungi isolated from wild populations of Arabidopsis thaliana in central Spain. The effects of these extracts against the plant-parasitic nematode Meloidogyne javanica , as well as two common plant pest insects ( Myzus persicae and Spodoptera littoralis ) were studied. Our results showed that 9 out of the 13 extracts exhibited significant nematicidal and/or insecticidal activity, indicating their biopesticide potential. Chemical analysis through GC-MS and LC-MS revealed that the active extracts contained a great variety of mostly extract-exclusive secondary metabolites, indicating a rich chemical diversity that was independent of the activity of the extract or origin of the fungal isolate. Our work highlights the importance of exploration into the metabolites produced by fungal endophytes, particularly those isolated from model plants like A. thaliana . This research lays the groundwork for future studies aimed at harnessing of endophytic fungi as a source of biopesticide products, contributing to sustainable agricultural practices and improved crop protection methods.