Ecological Stability of Short Stemmed Winter Rye Varieties

Abstract

The results of a 10-year (2008–2017) comparative study of winter rye varieties with recessive-polygenic (the first group) and dominant-monogenic (the second group) short stem type are presented. In each group, five varieties were estimated based on six traits: crop productivity, winter hardiness, plant height, 1000-grain weight, falling number, and viscosity of aqueous extract of grain meal. The following parameters were determined for each trait: phenotypic stability (SF), ecological variation (CV), ecological plasticity (bi), total (TAC) and specific (SAC) adaptive capacity, and breeding value of the genotype (BVG). Average productivity for groups of varieties was identical (6.69 and 6.62 t/ha, respectively); however, short stemmed varieties with dominant-monogenic type significantly differed by the best winter hardiness of plants (for 6.3%) and had a shorter stem (by 9.3 cm). The ecological variation of traits was significantly affected by all three factors: weather conditions of the year (75.5–95.0%), genotype of variety (1.1–2.5%), and variety to year interaction (2.9–22.3%). The year’s weather conditions influenced crop productivity most strongly (86.3% for the first group and 95.0% for the second group). For the winter hardiness trait, the influence of the variety to year factor was higher than for other traits, and it was respectively 9.3 and 22.3%. Ecological stability of the second group varieties was two times higher (CV = 12.4%) than that of the first group varieties (CV = 24.3%). The conclusion that winter rye varieties with a dominant-monogenic short stem had a lower norm of reaction to the adverse conditions of a rewintering developing during years with a high snow cover was made. Therefore, regions where the main limiting factor is low rewintering due to the strong infestation of plants with snow rot have to be the main cultivation area of such winter rye varieties. It is expedient to cultivate different types of short stemmed winter rye varieties in the main winter rye regions of Russia taking into account their agroecological specificity.