The study of salt resistance of winter wheat varieties zoned in Dagestan according to morphometric indicators

Abstract

Background. One of the results of global climate warming is salinization of soils. That is why, the problem of studying the resistance of plants to increased concentrations of salts in the soil becomes especially urgent. On the territory of Dagestan lowland zone, chloride and sulfate types of salinization of soils are most common. The purpose of the research was to study by laboratory methods the features of the growth and development of winter wheat in various salinization conditions. We set the task – to find out how various types of salinization (NaCl and Na2SO4) affect the processes of seed germination and the growth of seedlings of winter wheat. Materials and methods. 7 varieties of winter soft wheat (Triticum aestivum) zoned in the Republic of Dagestan were investigated: Thunder, Vassa, Tanya, Sila, Bezostaya 1, Don 105, Rostovchanka. Experiments were carried out in two versions: version I – germination of seeds of winter wheat varieties in different saline solutions in Petri dishes; II variant – germination in growing vessels using saline subtrat. Control tests were performed using distilled water. Results. In control experiments of both versions of the experiment, the seeds had good germination. In the medium with salts, the number of germinated seeds decreased, especially with sulfate salinization (by 67.2 %). The length of the roots with chloride salinization decreased by 78.1 %, with sulfate – by 91.3 %. The smallest deviation of experimental data from the controls was noted in the varieties of Vass and Rostovchanka. The largest deviation from control in Bezostaya 1 class in both saline solutions. In the vegetation version, with chloride salinization, the length of the roots decreased by 60.2 %, with sulfate salinization – by 63.1 %. Salinization in Petri dishes reduced the length of shoots by 92.5 and 95.5 % respectively. In the growing experience, this indicator decreased with chloride salinization by 59.0 %, with sulfate salinization – by 67.2 %. Only the growing version of the experience allows you to compare the morphometric parameters of the sheet. In the control test, the minimum sheet area was observed in the Thunder variety (78.2 mm2). The Strength variety exceeded other varieties in length, width and area of the leaf plate (190, 7 mm; 6,2 mm; 334,1 mm2 respectively). Under conditions of chloride salinization, the largest parameters were in the Vass variety, in which the escape length was 133.5 mm, the leaf length was 78.4 mm, and the leaf blade area was 169.0 mm2. The lowest indicators were in the Don 105 class (34.3 mm; 14.2 mm; 22.9 mm2 respectively). Under conditions of sulfate salinization, the largest parameters were noted in the Vass variety, in which the escape length was 104 mm, the length of the sheet was 70.4 mm, and the area of the leaf blade was 132.5 mm2. The lowest linear growth rates were for the Thunder variety, respectively, 33.8 mm; 14.0 mm; 22.9 mm2. Analysis of dry and raw biomass showed that, regardless of the type of salinization, there was a decrease in raw and dry biomass. Conclusions. Both sulfate and chloride salinization have a negative effect on seedlings of winter wheat, manifested in a decrease in their morphometric values. At the first stages of ontogenesis, sulfate salinization shows its negative effect more strongly compared to chloride salinization. The most resistant to both types of salinization is the soft wheat variety Vassa, zoned in the Republic of Dagestan, in which the inhibition of growth processes in conditions of salt stress was manifested to a lesser extent. The lowest salt resistance indicators were found for Don 105 and Spotless 1 wheat in both types of salinization.

Keywords

• winter wheat
• salt resistance
• chloride salinization
• sulfate salinization