The arbuscular mycorrhizal fungus Rhizophagus intraradices reduces the root rot caused by Fusarium pseudograminearum in wheat

Abstract

Root colonization with arbuscular mycorrhizal fungi (AMF) improves plant tolerance against soil-borne pathogens. The purpose of the present study was to explore the efficacy of the AMF Rhizophagus intraradices (N.C. Schenck & G.S. Sm.) as a biocontrol agent against Fusarium pseudograminearum (O'Donnell and Aoki) in wheat plants grown under greenhouse conditions. Parameters here analyzed included disease severity, plant morphological features, mycorrhizal structures within roots, and oxidative stress levels. AMF inoculation significantly counteracted on the negative effects of the pathogen F. pseudograminearum on plant parameters such as aerial and root biomass, number of spikes and plant height. These results suggest that AMF inoculation considerably reduced the F. pseudograminearum population density (75.7%) and disease severity (39%) compared to control. In addition, when compared with pathogen-infected plants, AMF-inoculated plants exhibited significant increases in the activity of antioxidant enzymes, along with a decrease in the levels of lipid peroxidation. This is the first work to show R. intraradices plays a significant role in wheat tolerance to F. pseudograminearum infection by maintaining the redox balance and competing for root sites to colonize.