Effects of Fusarium graminearum and Fusarium poae on disease parameters, grain quality and mycotoxins contamination in bread wheat (Part I).

BACKGROUND: Wheat is the most important winter crop in the world, being affected by the presence of fungal, mainly those belonging to the Fusarium genus. Fusarium head blight (FHB) is a serious disease that causes important economic damage and quantitative/qualitative losses, with Fusarium graminearum and Fusarium poae being two of the most isolated species worldwide. The present study aimed to evaluate the interaction between F. graminearum and F. poae and the effects on disease parameters, grain quality and mycotoxin contamination on five wheat genotypes under field conditions during three growing seasons. RESULTS: Statistical differences between Fusarium treatments were found for disease parameters, grain quality and mycotoxin contamination during the 2014/2015 growing season. High values of incidence (58.00 ± 8.00%), severity (6.28 ± 1.51%) and FHB index (4.72 ± 1.35) were observed for F. graminearum + F. poae treatment. Regarding grain quality, the results showed that the degradation of different protein fractions depends on each Fusarium species: glutenins were degraded preferably by F. graminearum (-70.82%), gliadins were degraded preferably by F. poae (-29.42%), whereas both protein fractions were degraded when both Fusarium species were present (-60.91% and -16.51%, respectively). Significant differences were observed for mycotoxin contamination between genotypes, with Proteo being the most affected (DON = 12.01 ± 3.67 µg g-1 ). In addition, we report that 3-ADON predominated over 15-ADON in the three seasons evaluated. CONCLUSION: Variations in plant-pathogen interaction (Fusarium-wheat pathosystem) should be considered at least in years with favorable climatic conditions for FHB development, as a result of the potential impact of this disease on grain quality and mycotoxin contamination. © 2019 Society of Chemical Industry.

Effects of Fusarium graminearum and Fusarium poae on disease parameters, grain quality and mycotoxin contamination in barley (part II).

BACKGROUND: Barley is one of the most sown crops in the world, with multiple uses such as human consumption, animal feed and for the malting industry. This crop is affected by different diseases, such as Fusarium Head Blight (FHB), that causes losses in yield and quality. In the last years F. graminearum and F. poae were two of the most frequently isolated species in barley grains, so the aim of this study was to evaluate the interaction between these Fusarium species and the effects on disease parameters, grain quality and mycotoxin contamination on five barley genotypes under field conditions. RESULTS: Statistical differences between Fusarium treatments for some parameters depending mainly on the year/genotype were found. The results showed that the germination process was affected by both Fusarium species. As to grain quality and the different hordein fractions, it was observed that F. graminearum affects preferentially D and C-hordeins. Different concentrations of nivalenol, deoxynivalenol and their acetylated derivatives (3-acetyl deoxynivalenol (3-ADON), 15-acetyl deoxynivalenol (15-ADON)) were detected. CONCLUSIONS: In the present work, no evidence of synergism between F. graminearum and F. poae were found regarding disease parameters and mycotoxin contamination. However, at least in the years with favorable climatic conditions to FHB development and depending on the barley genotype, a continuous monitoring is deemed necessary to prevent the negative impact on protein composition and germinative parameters © 2020 Society of Chemical Industry.