Fitness of three chemotypes of Fusarium graminearum species complex in major winter wheat-producing areas of China

Abstract

In China, Fusarium head blight is caused mainly by the Fusarium graminearum species complex (FGSC), which produces trichothecene toxins. The FGSC is divided into three chemotypes: 3-acetyldeoxynivalenol (3-ADON), 15-acetyldeoxynivalenol (15-ADON), and nivalenol (NIV). In order to predict the geographical changes in the distribution of these chemotype populations in major winter wheat-producing areas in China, the biological characteristics of twenty randomly selected isolates from each of the three chemotypes were studied. No significant difference was exhibited in the growth rate of 3-ADON, 15-ADON, and NIV isolates at 15°C. At 20°C and 25°C, the growth rate of 15-ADON isolates was the highest. At 30°C, the growth rate of NIV and 3-ADON isolates was significantly higher than that of 15-ADON isolates. The 15-ADON isolates produced the highest quantities of perithecia and two to three days earlier than the other two populations at each temperature, and released more ascospores at 18°C. The aggressiveness test on wheat seedlings and ears indicated there was no significant difference between the 3-ADON and 15-ADON isolates. However, the aggressiveness of NIV isolates was significantly lower than that of the 3-ADON and 15-ADON isolates. The DON content in grains from heads inoculated with the 3-ADON isolates was higher than the content of 15-ADON and NIV isolates. The results showed that 15-ADON population had the advantage in perithecia formation and ascospore release, and the 3-ADON population produced more DON in wheat grains. We suggested that distribution of these three chemotype populations may be related to these biological characteristics.

Gramineous weeds near paddy fields are alternative hosts for the Fusarium graminearum species complex that causes fusarium head blight in rice

“…Fusarium graminearum species complex isolates vary in their ability to cause disease in different hosts (Goswami and Kistler, ). In general, both 3ADON and 15ADON chemotypes of F. graminearum and F. asiaticum are more aggressive than NIV chemotypes of F. asiaticum , F. meridionale , and F. cortaderiae in wheat (Starkey et al , ; Spolti et al , ; Umpiérrez‐Failache et al , ; Liu et al , ; Nicolli et al , ; Yang et al , ; Amarasinghe et al , ). However, there have been few reports on the pathogenicity of FGSC isolates in rice (Goswami and Kistler, ; Lee et al , ; Gomes et al , ).…”

“…Our results showed that the occurrence of Fusarium mycotoxins is common in weed seeds that do not show FHB symptoms. Previously, only trace amounts of DON were detected in the weed flowers (Lofgren et al, 2018).…”

“…Moreover, some weed species have been identified as alternative hosts of FGSC, and their potential significance in the development of FHB epidemics has been demonstrated (Inch and Gilbert, 2003;Pereyra and Dill-Macky, 2008;Landschoot et al, 2011;Postic et al, 2012;Mourelos et al, 2014;Lofgren et al, 2018;Suproniene et al, 2019). The FGSC isolates from weeds were also pathogenic on wheat under artificial infection conditions (Pereyra and Dill-Macky, 2008;Lofgren et al, 2018;Suproniene et al, 2019). Although the presence of FGSC in weeds has been demonstrated, the role of FGSC inoculum in weed species in influencing FHB in rice remains largely unknown.…”

Resistance risk assessment for Fusarium graminearum to pydiflumetofen, a new succinate dehydrogenase inhibitor

“…Isolate of PH-1 was used and conidia were produced using the method described by Liu et al 19 Conidial suspensions were spread on V8 plates containing 5, 10 and 20 mg L −1 of pydiflumetofen, respectively. There were 300 plates for each concentration and each plate had 10 4 conidia.…”

Fitness traits of deoxynivalenol and nivalenol-producing Fusarium graminearum species complex strains from wheat

“…The 3-ADON strains from wheat were found at higher elevation regions with cooler winter and spring seasons, which suggested that climate could also shape species composition, besides cereal hosts (Del Ponte et al 2015). A recent study comparing 15-ADON and NIV strains of F. graminearum from China showed that the former grew faster at both 20 oC and 25 oC, produced higher amount of perithecia, and were more aggressive towards a wheat cultivar (Liu et al 2017). These findings of enhanced aggressiveness of the 15-ADON agree with studies in Brazil, although the NIV strains were of a different species ( F. meridionale ) (Spolti et al 2012a; Spolti et al 2013).…”