Dichlomethane (DCM) extract from the roots of Scutellaria luteocaerulea (skullcap) showed in vitro antifungal activity against Fusarium pseudograminearum and Fusarium culmorum, with IC50 values of 550 and 450 μg mL???? 1, respectively. Additionally, the effects of S. luteocaerulea on hyphal structures of the pathogens, spore germination, and mycelial growth were studied. According to the data obtained, the extract of S. luteocaerulea inhibited spore germination and mycelial growth of both pathogens tested. Additionally, the pathogens hyphae and spores were deformed when treated with the extract of S. luteocaerulea. Induced apoptotic characteristics were detected in both pathogens via the addition of the DCM fraction of S. luteocaerulea into the culture. The DCM fraction of S. luteocaerulea induced the production of reactive oxygen species (ROS) in both pathogens, as a characteristic of apoptosis. Activities of cell wall degrading enzymes (CWDEs) and production of deoxynivalenol (DON) were reduced. Also, the effect of the DCM fraction of S. luteocaerulea was investigated on the severity of Fusarium crown rot (FCR) and Fusarium head blight (FHB) diseases caused by both fungi on bread wheat. Plants treated with the DCM fraction of S. luteocaerulea showed an increased 1000-grain weight and decreased disease progress in greenhouse conditions. High performance liquid chromatography (HPLC) analysis revealed that the fraction had high concentration of wogonin. Therefore, the DCM fraction obtained from S. luteocaerulea could potentially be used in the future to protect wheat plants against F. pseudograminearum and F. culmorum.

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