Lucia Nedorost Ragasová

This study investigates Xanthomonas campestris pv. campestris (Xcc) incidence rates in cabbage, kale, and kohlrabi, focusing on the roots and stems over a 15-day period after sowing. Seeds were inoculated with Xcc, and infection levels were monitored using confocal microscopy combined with fluorescence in situ hybridization. Significant differences in incidence rates were observed across the 15 days using a scale from 0 to 5 (0–100% incidence). Kale exhibited the highest mean incidence rates in roots (3.64), while cabbage and kohlrabi showed greater variability (3.4–3.44). Stem infections were more severe, with kale showing the highest mean levels (4.16), followed by kohlrabi (4.0), and cabbage (3.68). In cabbage roots, incidence rates increased until day 11, after which a significant decline was noted, whereas stem Xcc incidence rates remained stable. Kale roots peaked on day 9, with significant fluctuations on days 13 and 15. Kohlrabi displayed moderate, stable root incidence rates over the 15-day period. In stems, kohlrabi showed a significant increase on day 11, followed by a drop on day 15. Regression analysis revealed a significant positive linear correlation between incidence rate and days of observation in kohlrabi roots. However, no significant trends were observed in stem infections across all species, where incidence rates were high and stable from day 7 onwards. Newly acquired data indicate that the incidence rate of Xcc development depends on the type of vegetable. However, the bacterial occurrence in the root parts does not always correspond with the intensity of Xcc colonization in the stem section of the plants. Even at lower levels of Xcc occurrence in the roots, damage to the vascular bundles can be fatal. These findings offer valuable insights into Xcc infection dynamics, contributing to improved disease management strategies for Brassica crops.

This study investigates Xanthomonas campestris pv. campestris (Xcc) incidence rates in cabbage, kale, and kohlrabi, focusing on the roots and stems over a 15-day period after sowing. Seeds were inoculated with Xcc, and infection levels were monitored using confocal microscopy combined with fluorescence in situ hybridisation. Significant differences in incidence rates were observed across the 15 days using a scale from 0 to 5 (0–100% incidence). Kale exhibited the highest mean incidence rates in roots (3.64), while cabbage and kohlrabi showed greater variability (3.4–3.44). Stem infections were more severe, with kale showing the highest mean levels (4.16), followed by kohlrabi (4.0) and cabbage (3.68). In cabbage roots, incidence rates increased until day 11, after which a significant decline was noted, whereas stem Xcc incidence rates remained stable. Kale roots peaked on day 9, with significant fluctuations on days 13 and 15. Kohlrabi displayed moderate, stable root incidence rates over the 15-day period. In stems, kohlrabi showed a significant increase on day 11, followed by a drop on day 15. Regression analysis revealed a significant positive linear correlation between incidence rate and days of observation in kohlrabi roots. However, no significant trends were observed in stem infections across all species, where incidence rates were high and stable from day 7 onwards. Newly acquired data indicate that the incidence rate of Xcc development depends on the type of vegetable. However, the bacterial occurrence in the root parts does not always correspond with the intensity of Xcc colonization in the stem section of the plants. Even at lower levels of Xcc occurrence in the roots, damage to the vascular bundles can be fatal. These findings offer valuable insights into Xcc infection dynamics, contributing to improved disease management strategies for Brassica crops.

The present article explores the importance of vineyard soil management. Studies on under-vine management have yielded a wide range of results, with some indicating potential benefits for vine growth and productivity. However, the methods of under-vine management and their specific effects on vineyard parameters require further research. The aim of this study is to evaluate the relationships existing between the different types of management of under-vine areas and the vegetation grown in this zone and to determine the effects of under-vine management on the yield and quality of Traminer grapevines. By examining various approaches, the research aims to provide insights into the optimising of vineyard management methods to achieve enhanced biodiversity and grape quality in this specific geographical context. The findings indicated that management of the under-vine area can impact the composition of plants, grape yield and quality. Under-row management had an effect on the number of plant species and their composition. The highest weight of bunches was found in MIX (a species from the Fabaceae family), while the lowest was found in the MECH treatment (bare soil). MULCH, MONO and MIX consistently had higher yeast assimilable nitrogen (YAN) in grapes than other treatments. In many of the evaluated parameters, the influence of the seasons was evident.

Rhubarb ( Rheum L.) is a well-known medicinal and culinary plant. Apart from its rich nutritional value, rhubarb contains a higher concentration of oxalates. In this study, the content of L-ascorbic acid (AA) and oxalic acid (OA) within three rhubarb species ( Rheum rhabarbarum, R. rhaponticum and R. palmatum × wittrockii ) differentiated to 16 accessions in a gene bank rhubarb collection (Lednice, Czech Republic) in the condition of conventional production in the South Moravia region during the harvesting period was evaluated. While L-ascorbic acid is essential in human nutrition, oxalic acid is considered toxic, and high doses may cause serious health issues. AA and OA content, the morphology evaluation and ISSR (inter simple sequence repeats)-based genetic analysis were performed. The results of this study confirm the significant influence of taxonomy and harvesting time on the content of AA in Rheum accessions. The content of AA was determined from 6 mg · 100 g ^-1 to 10 g · 100 g ^-1 fresh weight (FW) at the beginning of the harvesting season (May) up to 25 mg · 100 g ^-1 FW at the end of the harvesting period. The content of OA strongly varied from 300 mg · 100 g ^-1 to 1800 mg · 100 g ^-1 FW. Regarding the antinutrient character of oxalate, the optimal harvest period of this region was estimated to be from May to early June, when the OA content was the lowest. The role of AA as a precursor of oxalate formation in rhubarb was not affirmed by the results of this study.

Serendipita indica, a mutualistic root endophytic fungus, has gained attention for its potential to enhance plant health and resistance to various stresses. This study investigated the impact of S. indica (strain DSM 11827) on plant growth promotion and the management of black rot disease. This is a devastating bacterial ailment caused by Xanthomonas campestris pv. campestris, which affects cruciferous crops worldwide. The experiment was conducted under sterile conditions in a phytotron for 10 weeks. It involved the substrate and seed inoculation of S. indica in a cabbage crop. The findings suggested that S. indica establishes mutualistic relationships with cruciferous plants, positively influencing their growth while simultaneously reducing their susceptibility to black rot disease. Plant morphological and physiological parameters were enhanced by S. indica application. Additionally, bio stress markers were also enhanced in response to black rot disease. Moreover, disease severity was reduced by 27.9% and 18.8% in the substrate and seeds treated with S. indica, respectively. However, our findings did not report any antagonistic effect between S. indica and two pathogens, i.e., Xanthomonas campestris pv. campestris and Alternaria brassicicola under the in vitro test, suggesting that the suppression of black rot disease in cabbage seedlings was induced indirectly by S. indica. This study, therefore, underscores the promising prospect of utilizing S. indica to promote crop productivity and combat the destructive impact of black rot disease in cruciferous plants, contributing to more sustainable and resilient agriculture.

Introduction: Smart management in crop cultivation is increasingly supported by application of arbuscular mycorrhizal fungi (AMF) and plant growth-promoting microorganisms (PGPM), which sustain soil fertility and plant performance. The aim of this study was the evaluation of the effects of consortia composed of (Claroideoglomus claroideum BEG96, Claroideoglomus etunicatum BEG92, Funneliformis geosporum BEG199, Funneliformis mosseae BEG 95, and Rhizophagus irregularis BEG140) and PGPM (Azospirillum brasilense – AZ, or Saccharothrix sp. – S) on onion cultivated in growing media with a composition corresponding to a degraded soil. Methods: Three types of substrate formulations were used, with peat:sand ratios of 50:50, 70:30, 100:0 (v:v). The analysis of substrate parameters crucial for its fertility (pH, salinity, sorption complex capacity, and elements’ content) and characteristics reflecting onion seedlings’ performance (fresh weight, stress biomarkers, and elements’ content) was performed. Results: AMF colonized onion roots in all treatments, showing increasing potential to form intercellular structures in the substrates rich in organic matter. Additionally, co-inoculation with PGPM microorganisms accelerated arbuscular mycorrhiza establishment. Increased antioxidant activity and glutathione peroxidase (GPOX) activity of onion roots sampled from the formulations composed of peat and sand in the ratio of 100:0, inoculated with AMF+S, and positive correlation between GPOX, fresh weight and antioxidant activity of onion roots reflected the successful induction of plant acclimatization response. Total phenols content was the highest in roots and leaves of onion grown in substrates with 70:30 peat:sand ratio, and, in the case of roots, it was correlated with AMF colonization parameters but not with antioxidant activity.Discussion: AMF and PGPM efficiency in supporting onion growth should be linked to the increased onion root system capacity in mineral salts absorption, resulting in more efficient aboveground biomass production. AMF and PGPM consortia were effective in releasing minerals to soluble fraction in substrates rich in organic matter, making elements available for uptake by onion root system, though this phenomenon depended on the PGPM species. Microorganism consortia enhanced onion seedlings’ performance also in substrates with lower content of organic carbon through plant biofertilization and phytostimulation

Symbiotic interaction between plants and microorganisms in the rhizosphere is an important factor affecting plant growth and fitness. Arbuscular mycorrhiza fungi symbiosis increases resistance of the plants to stress factors, including pathogens. Tomato brown rugose fruit virus (ToBRFV) is an important destructive virus damaging tomatoes and peppers with losses that can reach 100%. It is listed on the list of current quarantine organisms in the Czech Republic. The aim of this study was to evaluate influence of root colonization with Funneliformis mosseae or/and Azospirillum brasilense on ToBRFV symptoms and viral titre reduction. Plants treated with arbuscular mycorhizal fungi (AMF) had lower symptom emergence after 14 dpi, however there was no difference in symptoms emergence after 21 dpi within all treatments. The highest colonization intensity by Funneliformis mosseae was detected in ToBRFV negative plants treated with both AMF and Azospirillum (AZO) and the lowest in ToBRFV positive plants with the same treatment (AMF + AZO). Colonization intensity of Azospirillum brasilense in all treated variants went from 20% to 41%. Results suggest that the combination of those two beneficial microorganisms in ToBRFV-infected plants negatively affected AMF colonization.

Increasing vulnerability of crops to pests and diseases, problems with soil erosion, a decline in biodiversity and a number of other negative impacts caused by agricultural intensification and monocultural production have been the subjects of many studies in recent decades. Today, cover cropping has become a promising practice to defuse these negative impacts, and it is emerging in many wine-producing regions, including the Czech Republic. However, the importance of permanent natural and semi-natural habitats in agricultural production should not be neglected. In this study, the effect of adjacent non-crop vegetation on plant and insect diversity was evaluated. The highest plant species richness of inter-row vegetation was found in vineyards with a high proportion (>40%) of non-crop vegetation within a 500-m radius. Regarding the agricultural impact of inter-row vegetation, the high proportion of non-crop vegetation could have been related to the higher presence of opportunistic and non-harmful weeds, compared with the presence of dangerous weed species. The number of insect families present in inter-rows was probably affected more by the vegetation coverage rate than by the proportion of adjacent non-crop vegetation. However, the occurrence of the Hymenoptera species, often representing beneficial organisms, was related to localities with a high proportion of adjacent non-crop vegetation.