Molecular Identification and Pathogenicity of Fusarium Fungi Causing Potato Dry Rot in Shanxi Province, China

In the present study, 70 representative strains of potato dry-rot pathogen fungi were collected and isolated from three potato-growing areas in Northern Shanxi Province to determine their distribution and composition. The aim was to determine their distribution and composition by investigating their genetic structure through morphological characterization and phylogenetic tree construction using three DNA fragments (<i>TEF1</i>, <i>RPB1</i>, and <i>RPB2</i>). The results showed that potato dry rot disease in Northern Shanxi Province, is caused by five pathogenic species: <i>Fusarium sambucinum</i>, <i>F. solani</i>, <i>F.oxysporum</i>, <i>F. acuminatum</i>, and <i>F. dimerum</i>, among which <i>F. sambucinum</i> is the dominant species, accounting for 87.14% of all the strains, and distributed primarily in various potato-growing areas in the region. This study is the first to show that <i>F. dimerum</i> is a component of the pathogenic complex causing potato dry rot and is distributed primarily in the basin and hilly regions with relative frequencies of 3.45% and 13.04%, respectively. <i>Fusarium acuminatum</i> is distributed only in the plateau regions with a relative frequency of 5.56%.