Estimation of drought tolerance of spring barley breeding material according to the residual water deficit indicator

Abstract

One of the key components of the efficient agricultural production is crop yield stability. In the Rostov Region, weather conditions are one of the factors limiting agricultural crop productivity. Drought is the most destructive natural phenomenon, causing far greater yield losses than any other abiotic stress. Uneven distribution of precipitation during a vegetation period of spring crops and frequent droughts requires development of varieties productive in arid conditions. The purpose of the current study was to compare drought tolerance of promising spring barley varieties and lines with different productivity levels, based on a water deficit indicator. The current paper has presented the study results of 17 spring barley samples of the Competitive Variety Testing in 2024–2025, according to the drought tolerance estimation using a residual water deficit indicator for vegetative plants. The trials were conducted at the FSBSI “ARC “Donskoy”, located in the region with irregular moisture, that created favorable conditions for selecting water stress resistant genotypes under natural aridity. Two years of testing have resulted in selecting the samples Zernogradskiy 1896, Zernogradskiy 1932, Zernogradskiy 1925, and Zernogradskiy 1927, which are characterized by high drought tolerance, minimal RWD values during flowering time (5.87–7.54%), and its slight increase (3.66–6.21%) by a milky ripeness phase (10.60–12.08%), and the largest productivity (5.2–5.6 t/ha). There have been identified reliable correlations between residual water deficit and productivity at the milky ripeness phase (r = -0.78 ± 0.16) and its increase (r = -0.70 ± 0.18). The results of the correlation analysis between the traits have shown that a residual water deficit can be used as a parameter to select valuable genotypes for drought tolerance breeding.