Sustainable agriculture with low inputs of chemicals and fertilizers has been recently attracting more attention from producers and researchers in the EU. The main reason for such attention is The European Green Deal—the EU’s latest growth strategy concerning environmental degradation and climate change. One of its main components is the Farm to Fork strategy, which especially features the reduction in pesticide and mineral fertilizer application and also supports the development of organic farming. At the same time, food demand is rising. These ambitious challenges require extensive research, development and innovation. Therefore, new non-chemical techniques for improving plant growth and resistance to biotic and abiotic stresses must be explored for their potential in this field. One of the most promising is the use of non-thermal plasma for such purposes. As this physical factor is a complex mixture of ions, atoms, electrons, radicals and molecules, its effect on plants and pathogens is also complex. This review presents different aspects of the effect of non-thermal plasma on seed germination, development of seedlings, plants and pathogens. The literature was explored to provide evidence for the possible use of non-thermal plasma for boosting plant growth and plant protection.

Endophytic fungi live their whole life within host tissues usually without any visible symptoms. Their vertical transmission (seed-plant-seed) has been well described and documented. However, horizontal transmission (plant-plant) needs more clarification. The aim of this study was to assess the extent to which endophytes move vertically in ecotypes of perennial ryegrass and whether there is evidence for the horizontal transmission of endophytes. Ecotypes from grasslands in Poland were collected in the form of living plants and used for vertical transmission analysis. Plants, the seed collected from these plants and plants grown from this collected seed were tested for endophytic infection. Provided that all produced seeds were viable and able to germinate and produce seedlings, the vertical transmission of Neotyphodium endophytes in perennial ryegrass ecotypes was nearly complete. For the horizontal transmission experiment, endophyte-hosting plants (E+) and endophyte-free plants (E-) of four cultivars were planted in the field in close proximity on small plots that were frequently mown. These studies revealed that after 7 months of growth next to E+ plants, the characteristic Neotyphodium spp. mycelia were found in E- plants, which was especially true for plants growing in close proximity to the infected plants. The occurrence of horizontal transmission of endophytes has not been previously demonstrated.