In this study, micro- and nanospectroscopic techniques were used to examine the aerial epidermis of a barley crop leaf cuticle to determine if there is a correlation between aerial morphological features and their chemistry. We believe this understanding may inform the design of nanoparticles (NPs) with improved and controlled NP-plant interactions and potential applications as foliar nanofertilizers. We compared three different Raman excitation wavelengthsNIR, Vis, and UVand evaluated the possibilities of nanospectroscopic techniques like tip-enhanced Raman spectroscopy (TERS) and nano-FTIR spectroscopy. All measurements were performed on a fresh leaf surface. The impact of excitation wavelength and other measurement parameters (laser power, exposure time) to obtain an optimal signal-to-noise ratio without photodamaging the leaf was systematically evaluated. The main compounds detected in the cuticle matrix were carotenoids, flavonoids, polysaccharides, phenolic compounds, and cuticular waxes. UV (325 nm) was found to be the most suitable excitation wavelength for obtaining the most intense signals from the cuticle while avoiding plant pigment signals.

• Publikační typ
• časopisecké články MeSH

Nanotechnologies have received tremendous attention since their discovery. The current studies show a high application potential of nanoparticles for plant treatments, where the general properties of nanoparticles such as their lower concentrations for an appropriate effects, the gradual release of nanoparticle-based nutrients or their antimicrobial effect are especially useful. The presented review, after the general introduction, analyzes the mechanisms that are described so far in the uptake and movement of nanoparticles in plants. The following part evaluates the available literature on the application of nanoparticles in the selective growth stage, namely, it compares the observed effect that they have when they are applied to seeds (nanopriming), to seedlings or adult plants. Based on the research that has been carried out, it is evident that the most common beneficial effects of nanopriming are the improved parameters for seed germination, the reduced contamination by plant pathogens and the higher stress tolerance that they generate. In the case of plant treatments, the most common applications are for the purpose of generating protection against plant pathogens, but better growth and better tolerance to stresses are also frequently observed. Hypotheses explaining these observed effects were also mapped, where, e.g., the influence that they have on photosynthesis parameters is described as a frequent growth-improving factor. From the consortium of the used nanoparticles, those that were most frequently applied included the principal components that were derived from zinc, iron, copper and silver. This observation implies that the beneficial effect that nanoparticles have is not necessarily based on the nutritional supply that comes from the used metal ions, as they can induce these beneficial physiological changes in the treated cells by other means. Finally, a critical evaluation of the strengths and weaknesses of the wider use of nanoparticles in practice is presented.

• Klíčová slova
• antibacterial effect, growth promotion, nanoparticles, nanopriming, seed germination, stress tolerance,
• Publikační typ
• časopisecké články MeSH
• přehledy MeSH