Multiplying <i>in vitro</i> plantlets of virus-free pre-basic potato under greenhouse conditions

Relevance. The survival and reproductive rates of mini-tubers obtained from in vitro potato plantlets were observed to increase under greenhouse conditions. This increase was diagrammed based on the experimental data. The aim of the study was to assess the effect of various types of bio-soils on the multiplication factor of mini-potatoes in vitro at the stage of original seed production in protected ground conditions.Materials and methods. The research was conducted in FSBSI “Federal Scientific Center of Agricultural Biotechnology of the Far East named after A.K. Chaiki” (Timiryazevsky settlement, Ussuriysk urban district, Primorsky kray) in 2021.In vitroplantlets of four potato varieties from different maturity groups were used as the research object: Meteor (early), Sante (medium early), Dachnyi (mid-season), and Smak (medium late). These potato varieties were admitted to use in the 12th (Far Eastern) region. The experiments were carried out in a 260 m2 greenhouse during spring and summer. Five variants of potting soil were studied. An agrochemical analysis of the soil mixtures was performed in the Laboratory of Agrochemical Analyses according to generally accepted methods. The reproductive rate of a variety was calculated from the number of survived plants in vials: the total reproductive rate and the reproductive rate of standard tubers (according to GOST 33996-2016). For this purpose, potato sizing squares and the visual method for the rejection of defective material were implemented.Results. Three out of five studied soil mixtures were determined to be effective for four potato varieties used in the experiments: a) 70% peat, 20% biocompost, and 10% vermiculite; b) 60% peat, 30% humus, and 10% sand; c) 60% peat, 20% humus, 10% humus from seaweeds, and 10% vermiculite.