Identification of Pathogens Causing Alfalfa Fusarium Root Rot in Inner Mongolia, China

Alfalfa Fusarium Root Rot (AFRR) is a serious soil-borne disease with complex pathogenicity. Diseased samples suspected of AFRR were collected from Hohhot, Ordos, Hulunbeier, Chifeng, and Bayannur in Inner Mongolia, China, leading to 317 isolates. The isolates identified as acuminatum, F. solani, equiseti, incarnatum, oxysporum, avenaceum, verticillioides, proliferatum, falciforme, tricinctum, virguliforme, redolens, the results pathogenicity testing showed that 12 species could cause alfalfa root rot. Among these, virguliforme have not previously been reported China. Although population structure pathogens differed different regions, dominant pathogenic was acuminatum. Fungicide toxicity tests seven fungicides inhibited which fludioxonil, kresoxim-methyl, triadimefon found be strongly toxic towards acuminatum EC50 values 0.09, 2.28, 16.37 μg/mL, respectively, suggesting these used alternative for control AFRR. this study can provide theoretical basis exploring occurrence epidemiology rot strategies its control.