ANALYSIS OF WINTER WHEAT VARIETIES FOR DROUGHT RESISTANCE IN THE CONDITIONS OF THE STEPPE OF UKRAINE (PART 3 – YEARS WITH DIFFERENT MOISTURE SUPPLY)

Abstract

The purpose of our research was the study and analysis of drought resistance of winter wheat varieties selected by the Institute of Climate-oriented Agriculture of the National Academy of Sciences of the Russian Academy of Sciences and the Selection and Genetics Institute of the National Center for Seed Science and Varietal Research of the National Academy of Sciences of the National Academy of Sciences in the conditions of the Southern Steppe of Ukraine. Research materials and methods. The reaction of 18 varieties of winter wheat to different growing conditions was studied at the Askanian State Agricultural Research Station in the village of Tavrychanka, Kherson region (46°33’12”N; 33°49’13”E; 39 m above sea level) during 2015/16–2019/20. Research was conducted under different conditions of irrigation: with irrigation and without irrigation. Analysis of the resistance of winter wheat varieties to stress was carried out using 17 indices of drought resistance. Research results and their discussion. The obtained experimental data make it possible to distinguish winter wheat varieties that significantly exceed the average variety in terms of productivity under irrigation (Yp): Maria and Shchedrist Odeska with a yield of 7.41–7.53 t/ha, in stressful conditions (Ys): Lyra Odeska – 6, 25 t/ha and the Shchedrist Odeska – 6.12 t/ha. According to the most indices (12), the Lyra Odeska variety was singled out as the most drought-resistant, the Shchedrist Odeska variety was distinguished according to eight indices, and the Rosynka variety – according to seven. The yield of wheat varieties under both moisture conditions has a high positive correlation (r = 0.832–1.000) with the indices MP, YI, STI, GMP, M1STI, M2STI, MSTI, HMP. Yield under irrigation is characterized by a high positive correlation (r = 0.715) with the TOL and SSPI indices, an average positive correlation (r = 0.542) with the SSI index, and an average negative r = (-0.499–-0.549) with the YSI, RDI and ISR indices on the other hand, there is no dependence with productivity under stress (r = -0.013–0.207). Yield under stress had a high correlation (r = 0.852) with the DI index and a moderate correlation (r = 0.420) with yield under irrigation. According to the results of the GGE biplot analysis, winter wheat varieties Kokhana, Askaniyska and Shchedrist Odeska can be characterized as moderately drought-resistant, Lyra Odeska is the most drought-resistant, Maria, Mudrist Odeska and Nyva Odeska can be classified as non-drought resistant varieties. Conclusions. Most of the indices had a high correlation with yield under both conditions, or a high or medium correlation with yield under irrigation and no correlation with yield under stress, so only one index, drought tolerance (DI), was selected. According to drought resistance indices and biplot analysis, Lyra Odeska is the most drought-resistant selected variety. The Shchedrist Odeska variety stood out according to eight indices, but according to the biplot analysis, it was characterized as medium resistance. According to seven indices, the Rosynka variety stood out, which was characterized by the smallest decrease in yield due to deterioration of moisture conditions, but also had low productivity under both conditions.