Transcriptomic and Metabolomic Analyses Reveal That Fusarium sp. Isolate Is Associated with Growth Promotion in Lolium perenne L.

Abstract

Simple Summary This study aims to address a pressing global issue: the excessive use of chemical pesticides and fertilisers has led to widespread soil contamination and the destruction of natural ecosystems; pathogenic fungi have long been regarded solely as harmful to crop growth, and their potential as beneficial microorganisms within healthy plants remains largely untapped. We screened healthy Chamelaucium uncinatum plants for a growth-promoting fungus that did not cause visible disease symptoms, to test its effect on Lolium perenne L.—a widely used forage crop—and to reveal how this fungus promotes better plant growth without causing harm. A fungal fermentation broth prepared from this strain increased the germination rate of Lolium perenne L. seeds from 61.5% to 82% and increased the final dry weight of the grass by 67.6%, whilst no disease symptoms were observed. In-depth transcriptomic and metabolomic analyses revealed that the fungal fermentation broth altered the plants’ transcriptional and metabolic profiles. This strain may be valuable for the future development of microbial inoculants or potential biofertilisers.