Soil salinity is a serious problem facing many countries globally, especially those with semi-arid and arid climates. Soil salinity can have negative influences on soil microbial activity as well as many chemical and physical soil processes, all of which are crucial for soil health, fertility, and productivity. Soil salinity can negatively affect physiological, biochemical, and genetic attributes of cultivated plants as well. Plants have a wide variety of responses to salinity stress and are classified as sensitive (e.g., carrot and strawberry), moderately sensitive (grapevine), moderately tolerant (wheat) and tolerant (barley and date palm) to soil salinity depending on the salt content required to cause crop production problems. Salinity mitigation represents a critical global agricultural issue. This review highlights the properties and classification of salt-affected soils, plant damage from osmotic stress due to soil salinity, possible approaches for soil salinity mitigation (i.e., applied nutrients, microbial inoculations, organic amendments, physio-chemical approaches, biological approaches, and nano-management), and research gaps that are important for the future of food security. The strong relationship between soil salinity and different soil subdisciplines (mainly, soil biogeochemistry, soil microbiology, soil fertility and plant nutrition) are also discussed.

As a result of global climatic changes, water deficiency is threatening food production for the increasing population worldwide, especially drought-sensitive crops, to which soybean belongs, by suppressing yield potentials. Drought stress can inhibit sown seeds’ germination and manipulate germination parameters. A controlled, two-stage experiment was conducted to investigate the effects of drought stress, induced by PEG (polyethylene glycol), on some germination parameters of two soybean cultivars; ‘ES Mentor’ and ‘Pedro’, in Debrecen, Hungary in 2018. At the first stage, 5 PEG concentrations; 10, 15, 20, 25, and 30%, besides control (0% PEG), were applied to each cultivar in 3 replicates. Results showed that both cultivars could not germinate when 25 and 30% of PEG were applied. Significant differences among PEG concentrations, between cultivars and their interaction were recorded. Based on these results, the second stage consisted of 6 PEG concentrations; 2.5, 5, 7.5, 10, 12.5 and 15% (besides control), also in three replicates. For both cultivars, germination ratio (GR) and root elongation (RE) decreased as the PEG concentration increased. Both germination energy (GE) and ultimate germination (UG) decreased, whereas mean period of altimate germination (MPUG) and percentage inhibition increased with increasing water stress. ‘ES Mentor’ could maintain higher (GR) than ‘Pedro’ under all PEG concentrations except 15%, whereas (RE) was lower under all concentrations. It was concluded that ‘ES Mentor’ can germinate better under different water deficiency levels; however, germinated seeds of ‘Pedro’ can tolerate relative water stress better, as the roots could elongate deeper searching for available water.

Application of various alternative nutrient supplies can partly be substituted by chemical fertilizers, resulting in economical use with less environmental strains. Biofertilizers containing living microorganisms promote nutrition uptake, but still there are questions regarding their application under stress conditions. One of the main abiotic factors that can induce stress is contamination of soils with toxic elements. In the course of intensive plant-growth conditions, considerable quantities of basic cations are removed from the soil, resulting in acidification and thereby enhancing the uptake of heavy metals by plants. Cadmium (Cd) toxicity is a major problem affecting crop productivity worldwide. The presence of Cd in the rhizosphere can cause stress responses and alteration in many physiological processes, including nitrogen metabolism, photosynthesis, carbohydrate metabolism, sulfate assimilation, and plant–water interactions. Once in the plant, Cd can enter the food chain, causing public health problems. The aim of our work was to investigate the effects of biofertilizers on plant production and nutrient uptake in some Cd-contaminated soils. Our results revealed that Cd accumulated primarily in the roots and transport to the shoots was rather low; however, there were differences between the two plants species. Plant uptake by sunflower was greater than by maize, and sunflower appeared to be more stress tolerant of Cd than maize. With the use of the bacterium-containing biofertilizer, the toxic effect of Cd was moderated.