Multiple invasive species affect germination, growth, and photosynthesis of native weeds and crops in experiments

Alien plant species regularly and simultaneously invade agricultural landscapes and ecosystems; however, the effects of co-invasion on crop production and native biodiversity have rarely been studied. Secondary metabolites produced by alien plants may be allelopathic; if they enter the soil, they may be transported by agricultural activities, negatively affecting crop yield and biodiversity. It is unknown whether substances from different alien species in combination have a greater impact on crops and wild plants than if they are from only one of the alien species. In this study, we used a set of common garden experiments to test the hypothesis that mixed extracts from two common invasive species have synergistic effects on crops and weeds (defined as all non-crop plants) in European agricultural fields compared to single-species extracts. We found that both the combined and individual extracts had detrimental effects on the seed germination, seedling growth, biomass, and photosynthetic performance of both crops and weeds. We found that the negative effect of mixed extracts was not additive and that crop plants were more strongly affected by invasive species extracts than the weeds. Our results are important for managing invasive species in unique ecosystems on agricultural land and preventing economic losses in yield production.

Evaluation of the Effect of Organic Matter from Invasive Plants on Soil Nematode Communities

Invasive plants can cause loss of biodiversity and degradation of ecosystems with varying degrees of impact on soil communities. Little is known about how the organic matter of these invaders in the soil affects soil properties and nematode communities. We performed a pot experiment with non-invaded grassland soil and organic matter from two invasive plants, Fallopia japonica and Solidago gigantea, to assess and compare the composition and function of the nematode communities and soil properties. We tested five treatments: (1) non-invaded grassland soil (S), (2) 100% decayed organic matter from F. japonica (OMF), (3) 100% decayed organic matter from S. gigantea (OMS), (4) 50% soil plus 50% organic matter from F. japonica (S/OMF), and (5) 50% soil plus 50% organic matter from S. gigantea (S/OMS). Analysis of nematode composition was conducted over five months from May to September. The number of identified genera and diversity index was highest in the S treatment. The soil moisture content was highest, pH and the diversity index were lowest and herbivorous nematodes were absent in OMF and OMS treatments. The addition of OMF and OMS to soil decreased the soil pH and moisture content and increased the contents of organic carbon and total nitrogen. In S/OMF, the abundance of herbivores was lower than in S and the abundances of bacterivores and fungivores decreased during the study period. In the S/OMS, a significantly high diversity index was observed, similar to that in the S treatment. The selected ecological and functional indices differed between S/OMF, S/OMS and S, but not significantly. Our findings indicated that the organic matter from the two invasive plants could differentially contribute to interactions with nematode communities. A decrease in productivity and the slowing of nutrient cycling demonstrated by the decrease in the abundances of bacterivores and fungivorous nematodes may be common adding organic matter of invasive plants to soil. A decrease in the abundance of herbivores after the application of organic matter of F. japonica could potentially be used as an ecologically friendly management strategy against plant parasitic nematodes.

Examination of the Effects of Domestic Water Buffalo (Bubalus bubalis) Grazing on Wetland and Dry Grassland Habitats

In nature conservation today, there is a global problem with the aggressive expansion of invasive plant species and the conservation of valuable grassland vegetation. Based on this, the following question has been formed: Is the domestic water buffalo (Bubalus bubalis) appropriate for managing various habitat types? How does grazing by water buffalo (Bubalus bubalis) affect on grassland vegetation? This study was carried out in four areas of Hungary. One of the sample areas was in the Mátra Mountains, on dry grassland areas where grazing had been applied for two, four and six years. The other sample areas were in the Zámolyi Basin, where wet fens with a high risk of Solidago gigantea and in a typic Pannonian dry grassland were investigated. In all areas, grazing was carried out with domestic water buffalo (Bubalus bubalis). During the study, we carried out a coenological survey, examining the change of cover of plant species, their feed values and the biomass of the grassland. According to the results, both the number and cover of economically important grasses (from 28% to 34.6%) and legumes (from 3.4% to 25.4%) increased in Mátra as well as the high proportion of shrubs (from 41.8% to 4.4%) shifted toward grassland species. In the areas of the Zámolyi Basin, invasive Solidago has been suppressed completely, the pasture has been converted completely (from 16% to 1%) and the dominant species has become Sesleria uliginosa. Thus, we have found that grazing with buffalo is suitable as a habitat management method in both dry grasslands and wet grasslands. Therefore, in addition to its effectiveness in the control of Solidago gigantea, grazing with buffalo is successful in both nature conservation and economic aspects of grassland vegetation.

SDS-PAGE Protein and HPTLC Polyphenols Profiling as a Promising Tool for Authentication of Goldenrod Honey

The aim of the study was to use protein and polyphenolic profiles as fingerprints of goldenrod honey and to apply them for verification of the labeled variety. The markers for 10 honey samples were correlated with the standard physicochemical parameters and biological activity measured in vitro as antioxidant, antifungal and antibacterial activities. Honey proteins were examined regarding soluble protein, diastase and SDS-PAGE protein profile. The polyphenolic profile was obtained with the use of the HPTLC and the antioxidant activity was detected with standard colorimetric methods. The antimicrobial effect of representative honey samples of different chemical profiles was verified against E. coli and budding yeast. It was found that the SDS-PAGE technique allows for creating the protein fingerprint of the goldenrod honey variety which was consistent for 70% of tested samples. At the same time, the similarity of their polyphenolic profile was observed. Moreover, specific chemical composition resulted in higher bioactivity of honey against tested bacteria and yeast. The study confirmed the usefulness of both SDS-PAGE and HPTLC techniques in honey authentication, as an initial step for selection of samples which required pollen analysis.

Evaluation of Soil and Ambient Air Pollution Around Un-reclaimed Mining Bodies in Nižná Slaná (Slovakia) Post-Mining Area

Thirty soil samples were taken, and the same number of moss (Dicranum scoparium) and lichen (Pseudevernia furfuracea) bags were exposed to detect environmental pollution in the former mining area Nižná Slaná. Soil and ambient air are influenced by hazardous substances, which leak from old mining bodies due to insufficient or completely missing reclamation. The total content of the risk elements (As, Cd, Co, Cu, Fe, Hg, Mn, Ni, Sb, Se, Pb, Zn) was determined in soil, moss, and lichen samples and in the bodies of Leccinum pseudoscabrum. Biological (soil enzymes-urease, acid phosphatase, alkaline phosphatase, fluorescein diacetate (FDA), ß-glucosidase) and chemical properties (pH) were determined in soil samples. Contamination factor (Cf), degree of contamination (Cd), pollution load index (PLI), and enrichment factor (EF) were used for soil and relative accumulation factor (RAF) for air quality evaluation. Contamination factor values show serious pollution by Cd, Fe, Hg, and Mn. Pollution load index confirmed extremely high pollution almost at all evaluated areas. Soil enzymes reacted to soil pollution mostly by decreasing their activity. Mosses and lichens show differences in the accumulation abilities of individual elements. Regular consumption of L. pseudoscabrum would provide the dose of Cd and Hg below the limit of provisional weekly intake. Based on the bioaccumulation index (BAF) values, L. pseudoscabrum can be characterized as an Hg accumulator.