Successful cultivation and high yields requires a lot of fertilization and irrigation, which in the soil causes excessive accumulation of salt that negatively affects the growth and development of plants. In arid and semi-arid areas, soil salinity is formed due to strong evapotranspiration and insufficient rainfall. The lack of drinking water is compounding the problem of saline soils, as farmers are forced into irrigation with water, which has a high concentration of NaCl and other salts. Fertilization and irrigation is also problematic in the cultivation of greenhouses, because in the enclosed areas there is no natural washing of salt in the lower layers of soil, and therefore the salinization is even faster. Each vegetable has a saline threshold, which determines the salt concentration limit above which there is a problem with the growth and development of the plant. Salt is well tolerated by pumpkins, peas, cucumbers, broccoli and tomatoes, but poorly carrots, eggplant, onion and salad. The consequences of cultivating plants on saline soils are: impeded water acceptance in seeds, because of higher osmotic potential, growth media cause toxicity that changes the activity of enzymes of nucleic acid metabolism, changes protein metabolism, disturbs the hormonal balance and reduces the utilization of seed stock. Increased salt absorption results in the accumulation of Na+ and Cl- in the plant, which results in faster aging and leaf fall, poor photosynthesis, poor root growth, etc. To avoid the effects of salt, different strategies began to be used: crossbreeding plants, desalination of the soil and today the most effective grafting plants to tolerant rootstocks. With these strategies we increase and improve crop on saline soils.
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