Assessment of ecological plasticity and stability of oil flax in the forest-steppe of the Middle Volga region

Abstract

The article presents the results of a comparative assessment of the ecological plasticity and stability of oilseed flax varieties and breeding lines based on the criterion of "yield". The study was carried out in the conditions of the south of the forest-steppe of the Middle Volga region in 2019–2023. The objects of the research were 8 promising breeding lines of oil flax. The released variety Kinelsky 2000 was adopted as the standard. The study also included the VNIIMK 620 variety as the most common in the regionʼs production areas. Two out of five years – 2020 and 2021 – were the most favorable for the formation of high yields of oil flax seeds with a positive value of the environment index. On average, over the years of the study, the flax seed yield varied within the range of 1.39–1.77 t/ha. The highest yield indicators were provided by the lines Kin × Wal/2011 k/s, L-4764, L-4910, L-7309/14-9 with a statistically significant excess over the standard variety of 11.9–23.8%. The most stable yield over the years were demonstrated by the lines Kin × Lin/2011 k/s, Kin × Wal/2011 k/s, Kin × Lin/2010 w/s and L-619223, the variation coefficient of which was the lowest among the studied varieties and lines (24.46–30.92%). When analyzing the ecological plasticity index, the lines most responsive to improved growing conditions were identified: L-4910 and L-7309/14-9, the regression coefficient of which exceeded one. Highly plastic lines L-4910, Kin × Wal/2011 k/s, characterized by strong responsiveness to changes in environmental conditions, are promising for inclusion in breeding programs for the creation of highly productive varieties of intensive oil flax.