Resistance to toxigenic fungi and their toxins in maize is a highly important research topic, as mean global losses are estimated at about 10% of the yield. Resistance and toxin data of the hybrids are mostly not given, so farmers are not informed about the food safety risks of their grown hybrids. According to the findings aflatoxin regularly occurs at preharvest in Hungary and possibly other countries in the region can be jeopardized. We tested, with an improved methodology (two isolates, three pathogens, and a toxin control), 18 commercial hybrids (2017–2020) for kernel resistance (%), and for toxin contamination separately by two–two isolates of F. graminearum, F. verticillioides (mg/kg), and A. flavus (μg/kg). The preharvest toxin contamination was measured in the controls. Highly significant kernel resistance and toxin content differences were identified between hybrids to the different fungi. Extreme high toxin production was found for each toxic species. Only about 10–15% of the hybrids showed higher resistance to the fungal species tested and lower contamination level of their toxins. The lacking correlations between resistance to different fungi and toxins suggest that resistance to different fungi and response to toxin contamination inherits independently, so a toxin analysis is necessary. For safety risk estimation, separated artificial and natural kernel infection and toxin data are needed against all pathogens. Higher resistance to A. flavus and F. verticillioides stabilizes or improves feed safety in hot and dry summers, balancing the harmful effect of climate changes. Resistance and toxin tests during variety registration is an utmost necessity. The exclusion of susceptible or highly susceptible hybrids from commercial production results in reduced toxin contamination.

Non‐infected and infected cereal crops, respectively, are treated in the afterglow of Ar/N2‐O2 surface‐wave microwave discharges at 2–8 mbar pressure. It is shown, that the germination and vigour of non‐infected seeds are not significantly effected, when barley is treated max 120 s at 2 mbar and maize 240 s at 4 mbar. On the other hand, seeds can be disinfected from the germination inhibitors Fusarium graminearum and Fusarium verticillioides. The most efficient treatment, which also increases the germination of infected seeds above 80%, for barley is the 3 min Ar‐20%O2 afterglow at 4 mbar, while for maize the 4 min Ar‐20%O2 + 2 min N2‐2%O2 at 8 mbar. The high NO content mixtures and the heating of seed surface by the recombination of O and N‐atoms inhibit barley germination.

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Drought and heat are severe environmental stresses that constantly affect plant growth and development. Maize (Zea mays L.) is known for its sensitivity to abiotic stresses, which often causes significant yield losses. With plant growth-promoting rhizobacteria (PGPR), the harmful effects of drought and heat stress on plants can be alleviated. The aim of the present study was to investigate the physiological traits of plants affected by drought stress in a treatment including four PGPR bacteria, two regimes of irrigation and two stages of phenophases, and the analysis of the influence of the individual factors and their combined effects, respectively. In addition, the investigations covered the testing of the nutrient acquisition ability and nutrient use efficiency, the plant growth stimulating effect of PGPR bacteria, and the analysis of the performance trials. The largest amount of soluble orthophosphate was produced by Pseudomonas putida (51.636 µg/cm3). This is significantly more than the amount of phosphate solubilized by Bacillus pumilus (15.601 µg/cm3), Pseudomonas fluorescens (14.817 µg/cm3) and Bacillus megaterium (14.621 µg/cm3). The germination vigour of the seedlings in the treatment with Pseudomonas putida was 55% higher, represented by the value of 15,237.125, in comparison with the control, with the value of 9792.188. The Pseudomonas putida treatment resulted in the most outstanding fresh/dry weight ratio (7.312) compared to the control (7.780), when the interaction between all factors was taken into account under stressed conditions at 50% female flowering stage. The highest dry matter content of the plants (18.344%) compared to the control (17.344%) was measured in the case of the Pseudomonas putida treatment during the milk stage of development under stressed conditions. In the field trial, the plants treated with KD2 (Bacillus pumilus and Pseudomonas putida) presented significantly higher results in the aspect of grain yield (6.278 t/ha) compared to the control (5.468 t/ha).

Gibberella ear rot (GER) is an important fungal ear pathogen of maize that causes ear rot and toxin contamination. Most previous works have only dealt with the visual symptoms, but not with the toxins of GER. As food and feed safety rankings depend on toxin contamination, including deoxynivalenol (DON), without toxins, nothing can be said about the risks involved in food and feed quality. Therefore, three susceptible, three medium-susceptible, and three medium-resistant mother lines were crossed with three testers with differing degrees of resistance and tested between 2017–2020. Two plot replicates and two fungal strains were used separately. The highest heterosis was found at the GER% with a 13% increase across 27 hybrids, including 7 hybrids showing negative heterosis (a higher hybrid performance above the parental mean), with a variance ranging between 63.5 and −55.4. For DON, the mean heterosis was negative at −35%, and only 10 of the 27 hybrids showed a positive heterosis. The mean heterosis for DON contamination, at 1% GER, was again negative (−19.6%, varying between 85% and 224%). Only 17 hybrids showed heterosis, while that of the other 17 was rated higher than the parental mean. A positive significant correlation was found only for GER% and DON; the other factors were not significant. Seven hybrids were identified with positive (2) or negative (5) heterosis for all traits, while the rest varied. For DON and GER, only 13 provided identical (positive or negative) heteroses. The majority of the hybrids appeared to diverge in the regulation of the three traits. The stability of GER and DON (variance across eight data sets) did not agree—only half of the genotypes responded similarly for the two traits. The genetic background for this trait is unknown, and there was no general agreement between traits. Thus, without toxin analyses, the evaluation of food safety is not possible. The variety in degrees of resistance to toxigenic fungi and resistance to toxin accumulation is an inevitable factor.