2023, Stępień, Arkadiusz, Wojtkowiak, Katarzyna, Cwalina-Ambroziak, Bożena, Waśkiewicz, Agnieszka

A field experiment with winter wheat (Triticum aestivum L.) cultivation was conducted at the Research and Education Centre in Tomaszkowo, Poland (53°72′ N; 20°42′ E) in the years 2013–2016. Fertilisation with nitrogen at 150 and 200 kg ha−1 and foliar application of manganese at 0.5 and 1.5 kg ha−1 were the research factors. Wheat infestation by Fusarium spp. was determined by the habitat conditions during crop growth. Neither nitrogen nor manganese fertilisation affected the presence of Fusarium spp. symptoms on wheat ears, but the infestation intensity decreased with increasing nitrogen and manganese content in the grain. Only the level of deoxynivalenol (DON) was correlated with Fusarium spp. infestation. Increasing the nitrogen fertilisation rate from 150 kg ha−1 to 200 kg ha−1 resulted in higher grain contamination with toxins. Supplementation of nitrogen fertilisation with manganese reduced the number of mycotoxins in wheat grain. The grain yield was mainly affected by the varied weather conditions during the wheat-growing periods. Neither nitrogen nor manganese fertilisation differentiated the wheat grain yield. The objective of this study was to examine the impact of the weather conditions and nitrogen and manganese fertilisation on the grain yield, occurrence of Fusarium head blight and mycotoxin level in winter wheat grain.

2023, Lalak-Kańczugowska, Justyna, Witaszak, Natalia, Waśkiewicz, Agnieszka, Bocianowski, Jan, Stępień, Łukasz

Fusarium proliferatum is a common hemi-biotrophic pathogen that infect a wide range of host plants, often leading to substantial crop loss and yield reduction. F. proliferatum synthesizes various mycotoxins, and fumonisins B are the most prevalent. They act as virulence factors and specific effectors that elicit host resistance. The effects of selected plant metabolites on the metabolism of the F. proliferatum strain were analyzed in this study. Quercetin-3-glucoside (Q-3-Glc) and kaempferol-3-rutinoside (K-3-Rut) induced the pathogen’s growth, while DIMBOA, isorhamnetin-3-O-rutinoside (Iso-3-Rut), ferulic acid (FA), protodioscin, and neochlorogenic acid (NClA) inhibited fungal growth. The expression of seven F. proliferatum genes related to primary metabolism and four FUM genes was measured using RT-qPCR upon plant metabolite addition to liquid cultures. The expression of CPR6 and SSC1 genes was induced 24 h after the addition of chlorogenic acid (ClA), while DIMBOA and protodioscin reduced their expression. The transcription of FUM1 on the third day of the experiment was increased by all metabolites except for Q-3-Glc when compared to the control culture. The expression of FUM6 was induced by protodioscin, K-3-Rut, and ClA, while FA and DIMBOA inhibited its expression. FUM19 was induced by all metabolites except FA. The highest concentration of fumonisin B1 (FB1) in control culture was 6.21 µg/mL. Protodioscin did not affect the FB content, while DIMBOA delayed their synthesis/secretion. Flavonoids and phenolic acids displayed similar effects. The results suggest that sole metabolites can have lower impacts on pathogen metabolism and mycotoxin synthesis than when combined with other compounds present in plant extracts. These synergistic effects require additional studies to reveal the mechanisms behind them.