Control of Fusarium head blight using the endophytic fungus, Simplicillium lamellicola, and its effect on the growth of Triticum aestivum

Abstract

The endophytic fungus Simplicillium lamellicola isolate 16,047 was obtained from root segments of winter wheat ‘AC Morley’ in 2016. This isolate has previously been found to antagonize Fusarium graminearum in dual culture, and preliminary growth room tests showed reduction of lesion lengths on wheat seedlings caused by F. graminearum. This study examined Fusarium head blight (FHB) control on different wheat cultivars under growth room, outdoor garden, and field conditions. In multiple growth room tests, spore suspensions of S. lamellicola applied at anthesis at three hours before the pathogen inoculation, reduced proportion of infected spikelets by 35–41% for FHB-susceptible cultivar ‘Wilkin’ and 49–58% for moderately resistant ‘Glenn’ at 13 days after pathogen inoculation. For outdoor garden tests with potted plants, S. lamellicola was sprayed three days before pathogen inoculation on spikes of ‘Glenn’, and this significantly reduced FHB by 75% to 88% at 13 days after pathogen inoculation. In two seasons of field trials, the biocontrol agent applied three hours before pathogen inoculation reduced FHB index (product of disease incidence and severity) for three wheat cultivars: susceptible ‘Wilkin’ (68% reduction), moderately resistant ‘AAC Scotia’ (76% reduction), and moderately resistant ‘Glenn’ (77% reduction) at 21 days after pathogen inoculation. As well, in growth room tests, S. lamellicola increased the growth of 'Glenn' at the seedling stage by 6% for shoot length, 18% for root length, 29% for fresh weight, and 13% for dry weight compared to the untreated control. The fungus S. lamellicola was effective against F. graminearum for reducing disease in the field and increasing plant growth, and could be further developed as a biological control agent.