Abstract

The formation of potato microtubers in vitro is discrete, and in order to increase its efficiency, it is important to ensure a regular supply of nutrients in a sterile vessel during plant ontogenesis. The aim of the research was to study the effect of phytohormones kinetin and IAA on the formation of microtubers in 20 potato varieties of different ripen time using two compositions of liquid media MS with 2% and 8% sucrose in the process of plant ontogenesis. The biomaterial was grown in plastic containers, the design of which allows the exchange of the nutrient medium in different phases of plant growth. The ontogeny of plants in tissue culture was significantly influenced by the ripening period of varieties. The early varieties were characterized by more intensive growth, their multiplication factor was 1.1-1.7 times higher than that of the middle early and mid-season varieties. The introduction of 0.4 mg/l kinetin into the nutrient medium had a positive effect on the formation of microtubers. For early varieties, the number of formed microtubers per plant increased by 1.2-1.8 pcs. compared to a hormone-free environment. The excess in later varieties was 0.8-0.9 pcs. per plant. The use of IAA without the addition of kinetin did not increase the number of microtubers. Complex application of phytoharmones promoted the growth of the fractional composition.