Pumpkins are widespread and popular fruits that need plenty of water. Cultivation in arid and semi-arid areas requires irrigation. Due to the low precipitation and strong evapotranspiration, the salt concentrations in the soil can greatly increase. The lack of drinking water only increases the problem of saline soils, as producers are forced to irrigate with water, which has a high concentration of NaCl and other salts. Due to the requirements of the market for large and high-quality crops, every cultivable land should be used, and therefore pumpkins often grow on the ground with a increased salt concentration. In general, pumpkins are tolerant to saline stress, but their tolerance varies. For example, for cucumbers, lose up to 50% of the crop in salt salinity, expressed as electroconductivity (EC), of 6,3 dS / m, the zucchini have the loss at 7.9 dS / m; Watermelons alredy lose half of the crop at 4.5 dS / m. The consequences of cultivating plants on saline soils are: impeded water acceptance in seeds when, due to 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 toxic effects of Na+, Cl- or sulphate (SO42-) which reduce the acceptance of essential minerals such as nitrogen (N), phosphorus (P) and potassium (K) and calcium (Ca2+), as well as increased Na+ and Cl- in the leaves of plants; reduction of photosynthetic pigments, as photosynthesis decreases when high concentrations of Na+ and Cl- accumulate in chloroplasts and chlorophyl. In order to avoid this problem, we can plant crossbreeded tolerant plants, use a financially demanding desalination of the soil, or we can graft plants onto a tolerant roothstocks, thereby improving and increasing the yield, while also utilizing the working surface with increased salt concentration.
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