@article{Vozhehova_Tyshchenko_Tyshchenko_Dymov_Piliarska_Smulska_2021, title={Assessment of drought resistance of alfalfa breeding material according to water regime indicators in the South of Ukraine}, volume={17}, url={https://journal.sops.gov.ua/article/view/228204}, DOI={10.21498/2518-1017.17.1.2021.228204}, abstractNote={<p><strong>Purpose</strong> is to evaluate the plant breeding material of alfalfa by the indices of water metabolism in different conditions of humidification, to determine the patterns of their manifestation, correlation ties between them and drought tolerance, to point out the best material for introduction into the plant breeding process.</p> <p><strong>Methods.</strong> Field, laboratory, statistical.</p> <p><strong>Results.</strong> During 2017–2020, 9 populations of alfalfa were studied by the indices of water regime: water content in the tissues, water deficit and water holding capacity of the leaves in the conditions of irrigation and natural humidification. The regularities of their manifestation were determined. By the data on the water content in leaves it was found out that it is high at irrigation (81.88; 79.63; 78.42%) and low (69.20; 70.81; 71.84%) without irrigation. Water content in leaves is closely related with water deficit, but the connection is inverse (<em>r</em> = -0.986 at irrigation and <em>r </em>= -0.863 at natural humidification). Water deficit in the populations was the highest (50.28–29.96–33.0%) in the stress conditions (without irrigation) and decreased in the plants at irrigation to 12.64–17.37–22.04%. Water deficit relates to <em>water holding capacity</em> of leaves: the greater water deficit, the lower <em>water holding capacity</em>. In the irrigated conditions, 13.9 to 17.3% was lost in 2 hours of the leaves wilting and 30.3–34.6% after 8 hours, and 3.78–4.31% in 1 hour. Water holding capacity ranged from 82.7 to 85.9% after 2 hours of the leaves wilting, and 61.6 to 69.7% after 8 hours. In the conditions of natural humidification, in the first 2 hours after wilting, the water content decreased by 8.5–11.7%, after 8 hours – by 16.5–22.6%. Water loss per one hour ranged from 1.78 to 2.84%, 1.5–2.0 times less than in irrigated plants. Water holding capacity was 82.3–91.5 and 77.0–91.5% after 2 and 8 hours, respectively. It was high (90.3–91.5 and 83.4–91.5%) in the following populations: LRH, M.q./M.agr., A.r.d. and M.agr.C. at water loss of 1.78–2.15%. A high inverse connection was found between water loss and water holding capacity after 2 and 8 hours: <em>r</em> = -0.652 and <em>r</em> = -0.963, respectively. There was a significant positive relationship between water holding capacity and drought tolerance (<em>r</em> = 0.597–0.696). High drought tolerance (56.9–58.2%) was recorded in the populations: M.agr.C., M.q./M.agr., LRH and Ram. D.</p> <p><strong>Conclusions. </strong>Regularities of changes in tissue water content, deficit and water holding capacity of alfalfa leaves during irrigation and in conditions of natural humidification were revealed. The relationships between water deficit and water holding capacity, water loss and water holding capacity, water hol­ding capacity and drought tolerance were determined. The best populations with high drought tolerance were selected to be introduced into the plant breeding process.</p>}, number={1}, journal={Plant varieties studying and protection}, author={Vozhehova, R. A. and Tyshchenko, A. V. and Tyshchenko, O. D. and Dymov, O. M. and Piliarska, O. O. and Smulska, I. V.}, year={2021}, month={Apr.}, pages={21–29} }