Assessment of the adaptability of winter rye hybrids for cultivation in the Forest-Steppe zone of Ukraine

The aim of the study was to substantiate the ecological and adaptive performance of modern winter rye hybrids for their use under different cultivation systems in the Forest-Steppe zone of Ukraine. The methodology combined field phenological and biometric observations, phytosanitary assessments, yield determination, and statistical analysis of variation parameters, ecological plasticity and stability based on the Eberhart-Russell model modified by Finlay-Wilkinson. The response of nine hybrids to contrasting abiotic factors was examined, and differences in the rate of spring vegetation recovery, formation of stem biomass and yield structure were identified. The level of winter hardiness and drought tolerance was analysed, demonstrating the ability of hybrids to maintain productivity under snow-deficient winters and uneven precipitation distribution. High ecological plasticity (bi =0.93-1.02) and stability (S2 di = 0.09-0.14) of the leading genotypes were revealed, confirming their universality across diverse agroclimatic conditions. It was established that SU Futturi, KWS Vinetto, KWS Tayo and SU Arvid achieved yields of 8.4-9.6 t/ha, minimised leaf-area losses during hydrothermal stress and exhibited strong resistance to major diseases. It was generalised that the introduction of these hybrids enhanced the resource efficiency of production technologies, reduced agrochemical pressure and supported the formation of ecologically resilient agroecosystems. The practical value of the study lies in identifying hybrids suitable for both conventional and organic farming systems, with the results being applicable to agricultural producers, advisory services and breeding centres when optimising varietal policy and implementing environmentally oriented cultivation strategies