The discoveries made over the past few years have modified the current immunological paradigm. It turns out that innate immunity cells can mount some kind of immunological memory, similar to that observed in the acquired immunity and corresponding to the defense mechanisms of lower organisms, which increases their resistance to reinfection. This phenomenon is termed trained innate immunity. It is based on epigenetic changes in innate immune cells (monocytes/macrophages, NK cells) after their stimulation with various infectious or non-infectious agents. Many infectious stimuli, including bacterial or fungal cells and their components (LPS, β-glucan, chitin) as well as viruses or even parasites are considered potent inducers of innate immune memory. Epigenetic cell reprogramming occurring at the heart of the phenomenon may provide a useful basis for designing novel prophylactic and therapeutic strategies to prevent and protect against multiple diseases. In this article, we present the current state of art on trained innate immunity occurring as a result of infectious agent induction. Additionally, we discuss the mechanisms of cell reprogramming and the implications for immune response stimulation/manipulation.

The present research investigated the response of silver maple (Acer saccharinumL.) to salt treatment. The short- and long-term effects of NaCl and CaCl₂treatments on plant fitness characteristics (growth parameters, leaf chlorophyll content) and biochemical stress-coping mechanisms (proline accumulation as well as enzymatic activities) were examined. We found that the silver maple response to salt stress strictly depended on salt type and dose—calcium chloride was less toxic than sodium chloride, but high concentrations of both salts negatively influenced plant growth. The accumulation of proline, slight changes in the activity of superoxide dismutase and marked changes in catalase and peroxidase activities in the roots and leaves indicated complexity of the plant response. It was also shown that after one year, enzymatic parameters were restabilized, which indicates plant recovery, but the reduced mass of seedlings suggests that one year is not enough to cope with the prolonged cyclic salt stress, both resulting from NaCl and CaCl₂application. Therefore, seedlings of silver maple should be considered as moderately susceptible to salinity. Hence, it is recommended to use silver maple on non-de-iced urban areas, while planting on often de-iced roads should be avoided.

Little is known about how light affects seed germination and revegetation of species of thermophilous oak forest. To reveal this relationship effects of white, red, far-red irradiations and dark incubation on germination of eight Potentillo albae-Quercetum taxa were examined. Attempts were also made to evaluate the influence of gibberellic acid and different nitrogen sources on the germination characteristics. Interaction between light and nitrogen was also studied. Freshly matured seeds of all taxa germinated very poorly, indicating presence of primary dormancy. Germination rates increased after wet-stratification treatment and were low in darkness. The highest concentration of the nitrogenous solutions that resulted in high germination level was 10 mM, whereas higher concentrations had a negative effect. Nitrate had the strongest influence which can be proved by a ‘gap detection’ mechanism for gaps in the vegetation. Far-red and red irradiation showed antagonistic effect on seed germination. There was a decrease in germination when far-red was followed by red and an improvement when red was followed by far-red treatment. Under red light, gibberellic acid enhanced germination of positively photoblastic taxa. It was concluded that light factor, associated with vegetation gaps, was the most important signal stimulating germination of the studied taxa.

The germination requirements of four taxonomically related taxa of Dianthus (D. arenarius L. subsp. borussicus Vierh., D. carthusianorum L., D. gratianopolitanus Vill., and D. deltoides L.) were studied under controlled conditions in a laboratory. A set of experiments were conducted to evaluate seed germination responses to storage period and cold stratification, different hydrogen ion concentrations (pH), potassium nitrate ([ ]), temperatures, and light conditions. Experiments were also performed to study the effects of sowing depth and water supply on seedling emergence. There were no differences in germination between seeds incubated under light or dark conditions for any of the taxa we studied. Germination percentages increased significantly with increases in temperature. The taxa of Dianthus we studied showed similar responses to sand burial, i.e., seeds placed on or near the soil surface had maximum emergence, and emergence declined with increasing depth of seed burial. In the studied taxa, germination was reduced by declining osmotic potentials. Cold stratification increased the germination rate, but did not affect final germination percentage of Dianthus seeds. A higher concentration of nutritious solutions (KNO₃) negatively affected the germination percentage. The results show that seeds of the studied taxa are potentially germinable in the species’ habitat at any time between April and October.

The presented study assessed the effect of bovine (BC) and fish (FC) waste-derived collagen, poly(hexamethylenebiguanide) hydrochloride (PHMB) and waste dolomite on the emergence of seedlings, growth and development of pea (Pisum sativum L. ‘Lasso’) plants. The seed coating method was used to apply the binding agents. Some of the studied agents were showed to significantly affect the index of emergence velocity (IEV) and of emergence synchrony (IES), but not the final emergence percentage (FEP). The results showed that treatment of the pea seeds with BC, FC and PHMB had a slightly positive effect on plant growth, whereas negative effects of dolomite were observed, i.e., detrimental differences in morphological traits of stipules. Moreover, BC, FC and PHMB improved maximal efficiency of PSII (F_V/F_M) and did not negatively influence chlorophyll content. Analyses demonstrated positive effects of FC and PHMB and negative ones of BC and dolomite on elemental composition of roots and shoots of the studied plant species. We suggest that the FC and PHMB can be used as promising agents for improvement of plant growth, whereas usage of BC and dolomite should be limited.