Prospective varieties of dahlia cultural (Dahlia x cultorum Thorsr. et Reis.) when growing for shearing in conditions of protected ground

Relevance. In terms of the richness of colors, shapes and sizes of inflorescences and relative unpretentiousness during cultivation, as well as the duration of flowering of a dahlia, the cultural has no equal. Basically, this flower crop is grown in the open field and used for landscaping areas. Dahlias, due to their decorative properties, are a promising crop for cutting. But the growth in the volume of industrial cultivation of cut dahlias has long been constrained by two negative factors - the low life expectancy of cut flowers, and the fact that not all varieties of cultivated dahlias are suitable for cultivation in greenhouses. Therefore, the search for varieties that meet the aforementioned properties is an especially urgent task.
Material and methods. The material for the study was 10 varieties of Dahlia × cultorum Dutch selection. They belong to different groups of dahlias – spherical: Souvenir d'Eté, The Voice, Jowey Winnie; decorative – Orion, Café au Lait, Fleurel, Karma Choc and pompom dahlias: Little William, Cornel Bronze, Petra's Wedding, All tubers were planted in phytotron beds. Phenological observations of plants were carried out according to the Methodology of State Variety Testing of Ornamental Crops. During the growing season, the following indicators were determined: the onset of phenological phases of development, the dynamics of plant growth, the number and size of inflorescences, the length of the peduncle, the duration of flowering.
Results. It was found that all the studied varieties of cultural dahlias have a high decorative effect and are suitable for growing for cutting in greenhouse conditions. Growing plants in a phytotron allows you to get a high-quality cut almost two months ahead of time, as well as have a longer and more abundant flowering. It was found that the Café au Lait cultivar is not entirely suitable for cut cultivation in greenhouses or requires the development of cultivation technology that is individual for this cultivar. It was found that the Fleurel variety surpasses other studied varieties in terms of decorativeness, inflorescence size, peduncle length, onset time and flowering duration. A significant disadvantage of the variety is its high growth and fragility of the peduncles. The most popular cut varieties were Fleurel, Petra's Wedding, Jowey Winnie and Little William. It was found that the studied varieties of cultural dahlias were distinguished not only by high decorativeness, but also by high durability in a vase from 5 to 7 days.

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