Effect of Domestication on the Phenotype of Einkorn Wheat

The article analyzes influence of domestication on the trait complex of einkorn wheat. The presence of genetically very close forms—two wild (Triticum monococcum L. subsp. aegilopoides (Link) Thell., Triticum urartu Tumanian ex Gandilyan) and two cultivated (T. monococcum L. subsp. monococcum, T. monococcum subsp. sinskajae (Filat. and Kurkiev) Valdés and H.Scholz) in the einkorn gene pool makes it a convenient object for studying effect of domestication. This study establishes three main traits that define the essence of the "domestication syndrome": increase in seed size, absence of spontaneous ear brittleness, ease of grain threshing (decrease in hullness) in cultivated einkorns compared to wild ancestral forms. It was found that during the transition from wild to cultivated einkorn, stem height and upper internode length decreased but the indices of plant development rate, weight of kernels per ear and 1000 kernel weight increased. At the same time, the traits related to the potential productivity—weight of whole spike and spikelet number in ear—did not change whereas indicators of this potential realization (actual productivity)—kernel number per spike and spike length—have decreased. Multivariate analysis of the einkorns characteristics identified two main components that generally explain 78% of variability. Clustering of the einkorn accessions according to 10 traits made it possible to divide the accessions into groups of differential significance for breeding. Suggestions for the rational use of einkorn wheat accessions in breeding were formulated. In cultivated eincorn, the traits are more correlated than in the wild ones, indicating greater physiological homeostaticity of wild ancestral species and less homeostaticity of cultivated einkorn.