Salt Tolerance of Wheat (<i>Triticum aestivum</i>) Varieties Grown Under Laboratory and Field Conditions

Abstract

High salt concentration limits plant growth. Wheat (<i>Triticum aestivum</i>) is sensitive to toxic levels of mineral salts. Therefore, studies of the level of salt tolerance of various wheat varieties are of crucial importance. Plant resistance to stress factors is often controlled not by one, but by several factors. In this study, we carried out a thorough characterization of two wheat varieties, Uchitel and Orenburgskaya 22, which exhibit different levels of salt tolerance in laboratory and field conditions. The biomass of wheat cultivar Orenburgskaya 22 when grown in field conditions under salinity is higher than that of cultivar Uchitel, although the length of the root system decreases compared to cultivar Uchitel. The use of the methods of fluorescence and light-optical microscopy made it possible to obtain more complete information on the salt sensitivity of wheat. Variety Orenburgskaya 22 is more resistant to the negative effect of sodium chloride in comparison with variety Uchitel. The plant response to abiotic stress is a complex process in which many genes are involved. We analyzed the expression of genes for transporters (HKT), superoxide dismutase (SOD), and MYB genes. Under the influence of sodium chloride, the level of expression of genes of the MYB family increased, while the level of expression of genes of the HKT family decreased in both Uchitel and Orenburgskaya 22 both in the laboratory and in the field. Our results indicate that in-depth analysis under various growing conditions is important for studying wheat tolerance to salt stress.