Unraveling the antifungal composition of bitter orange decoction against the melon pathogen Fusarium jinanense.

Bitter orange (Citrus aurantium) is an important source of essential oils with high antimicrobial activities, however the composition and antifungal potential of the decoction peels is little explored. This study assessed the peel decoction's chemical profile at the secondary metabolism level and its antifungal activity against the melon phytopathogen Fusarium jinanense. The decoction's antifungal potential was investigated using a bioassay-guided fractionation approach based on Solid-Phase Extraction (SPE) and LC-HRMS/MS analysis. Coumarins and flavones were the most abundant classes of compounds in the high-value fractions responsible for up to 61% of the mycelial inhibition of F. jinanense. Overall, this study has presented for the first time the chemical composition, the antifungal potential of the decoction of C. aurantium peels and the compounds associated with these results. This strategy can guide the exploration of under-explored food sources and add value to compounds or fractions enriched with bioactive compounds.

Fusarium elaeidis Causes Stem and Root Rot on Alocasia longiloba in South China.

Alocasia longiloba is a popular ornamental plant in China, however pests and diseases associated with A. longiloba reduce the ornamental value of this plant. From 2016 to 2021, stem and root rot has been observed on A. longiloba in Guangdong Province, China. Once the disease became severe, plants wilted and died. A fungus was isolated from the diseased stem and identified as Fusarium elaeidis using both morphological characteristics and molecular analysis of DNA-directed RNA polymerase II subunit (rpb2), translation elongation factor-1α (tef1) gene and ß-tubulin (tub2) sequence data. The pathogenicity test showed the fungus was able to produce typical symptoms on A. longiloba similar to those observed in the field. The original pathogen was reisolated from inoculated plants fulfilling Koch's postulates. This is the first report of Fusarium elaeidis causing stem rot on A. longiloba. These results will provide a baseline to identify and control diseases associated with A. longiloba.

Acetylsalicylic acid treatment reduce Fusarium rot development and neosolaniol accumulation in muskmelon fruit.

Fusarium rot of muskmelon is a common and frequently-occurring postharvest disease, which leads to quality deterioration and neosolaniol (NEO) contamination. New strategies to control postharvest decay and reduce NEO contamination are of paramount importance. The effects of acetylsalicylic acid (ASA) treatment on the growth of Fusarium sulphureum in vitro, and Fusarium rot development and NEO accumulation in fruits inoculated with F. sulphureum in vivo were investigated. The results showed that ASA inhibited the growth of F. sulphureum, evident morphological and major cellular changes were observed under the microscope. In vivo testing showed that 3.2 mg/mL ASA significantly suppressed Fusarium rot development and NEO accumulation after 6 and 8 d of pathogen inoculation. Meanwhile, Tri gene expressions involved in NEO biosynthesis were down-regulated after treatment. Taken together, ASA treatment not only reduced Fusarium rot development by inhibiting the growth of F. sulphureum, but decreased NEO accumulation by suppressing NEO biosynthesis pathway.