This research paper is devoted to the application of cluster analysis for evaluating samples of soft spring wheat by elements of crop structure. The purpose of the study is to analyse the intraspecific and interspecific variability of morphological features of samples of spring wheat of various ecological and geographical origin according to 8 morphological features. Observations were carried out in 2018-2020 in the training and experimental production centre "Doslidne pole" of the Kharkiv National Agrarian University named after V.V. Dokuchaev. The cluster analysis of the collection of spring wheat samples, which included 76 samples of various ecological and geographical origin, allowed the study to assess the following features: the presence of awns, the colour of awns, the colour of ear scales, the pubescence of leaves, the pubescence of the subcrown internode, the pubescence of the ear internode, the colour of caryopsis, the colour of straw. The results of analysis of the phylogeny of various types of spring wheat by cluster analysis using morphological markers to determine homogeneous groups are presented, and the affected tree of systematic formation of clustering groups is established. Based on the cluster analysis, two separate groups of soft spring wheat samples were identified according to the complex of plant productivity elements. Samples are grouped into each cluster depending on the quantitative characteristics of the crop structure and their interaction with each other. In general, all samples over the years of study showed good results, namely based on "colour of awns", of particular note are the samples of the Tr. persicumspecies. According to the results obtained, all samples have good indicators, and cluster analysis of soft spring wheat samples allowed identifying groups of plants that exceed the parent forms in the optimal set of economically valuable traits, which would allow for a more purposeful selection of valuable forms based on certain traits.
Keywords: model, clustering, cluster, dendrogram, evaluation, spring wheat.