The Major Fusarium Species Causing Maize Ear and Kernel Rot and Their Toxigenicity in Chongqing, China.

, , and were identified as the predominant fungi among 116 isolates causing maize ear and kernel rot, a destructive disease in Chongqing areas, China. The toxigenic capability and genotype were determined by molecular amplification and toxin assay. The results showed that the key toxigenic gene was detected in 47 and 19 isolates. Among these, and isolates mainly produced fumonisin B₁, ranging from 3.17 to 1566.44, and 97.74 to 11,100.99 µg/g for each gram of dry hyphal weight, with the averages of 263.94 and 3632.88 µg/g, respectively, indicating the isolates on average produced about an order of magnitude more fumonisins than did in these areas, in vitro. Only NIV genotype was detected among 16 and three isolates. Among these, 11 isolates produced NIV, varying from 17.40 to 2597.34 µg/g. ZEA and DON toxins were detected in 11 and 4 isolates, with the toxin production range of 8.35-78.57 and 3.38-33.41 µg/g, respectively. Three isolates produced almost no mycotoxins, except that one isolate produced a small amount of DON. The findings provide us with insight into the risk of the main pathogenic species and a guide for resistance breeding in these areas.