Barley plants were exposed to favourable and reduced water availability during growth under ambient and reduced ultraviolet exposure. Element composition and morphological, biochemical, physiological, and optical traits of barley leaves growing under these four treatments were investigated. Water shortage affected the element composition of barley plants significantly. Silicon and chlorine levels were the most reduced by water shortage, followed by calcium, phosphorus, and sulphur, while potassium levels were not affected. These plants did not undergo water shortage stress, as photochemical efficiency of photosystem II and pigment contents were similar across all treatments. Water shortage affected reflectance of light across the whole spectrum, while ultraviolet radiation affected optical properties of the barley leaves in the UV region only.
The influence of selected factors on diversity and composition of tychoplanktonic diatom community in limnocrene spring Zelenci was investigated. Over 100 different diatom species were identified, among which the most abundant were Achnanthidium minutissimum and Denticula tenuis. The most significant impact on species composition of tychoplanktonic diatom community had conductivity of the water and month of the sampling. Diversity negatively correlated with concentration of orthophosphate and positively with pH and water level. The values of trophic index negatively correlated with temperature of the water and indicated oligo-mesotrophic to even meso-eutrophic conditions. Benthic species from low profile ecological group dominated the tychoplankton community with the share 30-72%. High profile and motile species characteristic for benthos also reached higher shares on average than euplanktonic species that indicate the essential role of underwater springs maintaining species-rich tychoplanktonic community.
Metallic pollutants, including Pt, are disproportionately emitted into air as nanoparticles (NPs), whose retention and uptake by plant leaves is affected by their foliar characteristics, such as wrinkling, waxiness, and the presence of trichomes. In this study, the influence of foliar surface free energy (SFE) on Pt NP retention and translocation was investigated using arugula (low SFE) and escarole (high SFE) plants. Our results show that low foliar SFE is significantly correlated with increased Pt NP retention and decreased internalization and translocation to roots due to stomata closure from likely shading effects. These results indicate that foliar SFE should be included as a relevant factor where environmental and food chain transfer and the development and use of agricultural nanomaterials are concerned.
Alterations in phenolic contents were studied in Esca symptomatic (Sym) and asymptomatic (Asym) vines of 'Cabernet Sauvignon' based on wood conditions (healthy, HLT; necrotic, Nec; and rotten, Rot) and vine parts (head, trunk, and rootstock). In Asym vines, only Alternaria alternate was identified in Nec wood, while the HLT wood of Sym vines was colonized by Botryospaeriaceae sp. and Aureobasidium pullulans, Nec wood by Fomitiporia mediterranea, and Rot wood by Fomitiporia mediterranea and Phaeomoniella chlamydospora. Esca infection caused a significant accumulation of gallic acid, total flavanols, stilbenes (STB), and total analyzed phenolics (TAP) in all studied woods, especially in Nec wood. The obtained results suggest that the alteration in phenolics differed not only due to Esca infection but also due to the wood conditions and vine part, which might reflect the impact of the duration of the presence of the pathogen in different parts of the vine.
Microplastics, small plastic particles below 5 mm, have become one of the central concerns of environmental risk assessment. We studied the effect of polyethylene microbeads from cosmetic products on duckweed (Lemna minor), a freshwater floating plant. Specific frond growth rate and content of photosynthetic pigments in duckweed fronds were not affected by polyethylene microbeads, but these microbeads significantly affected the root growth by mechanical interaction and reduced the viability of root cells.