Breeding value of grain sorghum genotypes under contrasting moisture conditions

Abstract

Purpose. To conduct a comprehensive breeding evaluation of grain sorghum genotypes based on the emergence- to-flowering period, grain moisture content, yield, and interannual yield variability under contrasting hydrothermal conditions, and to identify productive and relatively stable source material for breeding in the Northern Steppe of Ukraine. Methods. The study was conducted in 2023-2025 at the Synelnykove Breeding and Research Station of the State Institution Institute of Grain Crops of the National Academy of Agrarian Sciences of Ukraine. Seventeen accessions were evaluated in a competitive variety trial; seven genotypes were selected for detailed three-year comparison: Lan 59 (standard), Smotrych, Vyshyvanka, Dn 35, F₅ (Nyzkorosle 93s × G 230 v. zp.), D 104, and Karshakh. The harvested plot area was 25 m², with four replications and randomized treatment placement. The emergence-to-flowering period, grain moisture content, and grain yield adjusted to 14% moisture were determined. Data were processed by analysis of variance with LSD₀.₀₅; interannual variability was assessed using the coefficient of variation. April–September precipitation totaled 239, 139, and 191 mm, while the hydrothermal coefficient was 0.76, 0.41, and 0.59, respectively. Results. Depending on genotype and year, grain yield ranged from 1.37 to 6.58 t ha⁻¹. The highest overall productivity was recorded in 2023, whereas the greatest decline occurred in 2025. Averaged over three years, D 104 produced the highest yield, 4.89 t ha⁻¹, exceeding the standard Lan 59 (3.57 t ha⁻¹) by 37.0%. Dn 35 and Karshakh yielded 4.66 and 4.53 t ha⁻¹, respectively. The lowest interannual variability was recorded for F₅(Nyzkorosle 93s × G 230 v. zp.), with CV = 30.7%; the corresponding values for D 104 and Dn 35 were 37.5 and 39.7%. Smotrych and Karshakh were more variable, with CV values of 61.4 and 59.4%. The lowest hydrothermal coefficient occurred in 2024, while the lowest yield was recorded in 2025, indicating that grain productivity depended not only on total precipitation but also on its temporal distribution and the temperature regime during critical developmental stages. Conclusions. D 104 is recommended as a source of high productivity, Dn 35 as a genotype combining high mean yield with more moderate interannual variability, and F₅ (Nyzkorosle 93s × G 230 v. zp.) as the form with the lowest coefficient of variation among the evaluated genotypes. Further research should include multi-environment testing, instrumental monitoring of plant-available soil water during critical growth stages, and quantitative genotype-by-environment interaction analysis.