Trichoderma atroviride induces biochemical markers associated with resistance to Fusarium culmorum, the main crown rot pathogen of wheat in Algeria

Fusarium culmorum (W.G. Sm.) Sacc. is the main causal agent of wheat crown rot in Algeria, which affects the yield and seed quality due to the presence of mycotoxins. In the present study, we evaluated the effect of the biocontrol agent Trichoderma atroviride (Ta.13) P. Karsten on the antioxidant enzymes activities (peroxidase and catalase), as well as on phenolic and protein content of three wheat varieties, compared to uninoculated controls. The data showed that T. atroviride induced systemically higher levels of these factors. In general, maximum induction was recorded in the Waha variety, followed by Ain Abid, when plants were co-inoculated by both Ta.13 and F. culmorum versus F. culmorum only. At the same time, lowest levels of these factors occurred in the Vitron variety. The highest accumulation of phenols in basal areas of the wheat plant occurred in the Waha variety, with an increase of up to 1400% compared to the control, and, also in Waha, there was the greatest increase of peroxidase activity in the foliar tissues, up to 282% of the control. Protein content in Waha in the plant collars increased 66% in co-treated plants. On the other hand, the highest increases in catalase activity were detected in the basal stem and leaves of Ain Abid variety co-inoculated with Ta.13 and F. culmorum, with 641% and 788% increases in these tissues, respectively. Our results show that there are variety-dependant physiological changes exhibited by the wheat plant during interaction with the pathogen and the antagonist.