Relevance. Hybrid seed production of carrots is carried out on a three-line basis, which suggests the presence of a male sterile maternal line and a fertile paternal line. For the reproduction of a male sterile line, a maintainer line is needed. The process of creating an isogenic pair of a manly sterile line – a maintainer line is of great complexity. As a maintainer line, it is necessary to use only a plant – a homozygote Cyt N msms for the core genes providing sterility, but with a normal cytoplasm. The purpose of the work is the creation of maintainer line for the sterility of carrots from the population of the Rogneda variety.Methods. Research were carried out: in 2016, at the experimental base of the Voronezh Vegetable Experimental Station (Voronezh Region); in 2017 - 2019, at the breeding center of All-Russian Research Institute of Vegetable Growing – branch of Federal State Budgetary Scientific Institution Federal Scientific Vegetable Center (Moscow Region). The material for the work was seed plants and roots of the Rogneda variety and hybrid, inbred, backcross progenies obtained from this population. Breeding methods: hybridization, inbreeding. Crosses used: simple direct and complex return (backcrosses), inbreeding.Results.Research revealed the possibility of searching for a maintainer line in the Rogneda variety. The P43f inbred progeny is potential line B, which maintains the CMS trait of the petaloid type at 100%. Of the 67 hybrid progenies, only P43st x P43f was left, in which all plants with male sterility. 65 hybrid progenies contained both sterile and fertile plants. Associated 65 inbred progenies had sterile and fertile plants, i.e. it makes no sense to try to obtain a maintainer line is needed. The process of creating an isogenic pair of a manly sterile line – a maintainer line from such fertile plants. Hybrid progeny of P4st x P4f had 100% fertile plants. The inbred progeny of P4f was represented only by fertile plants.

Carrot is one of the main vegetable crops due to its high yield and long-term preservation during winter storage. In the Amur Region, the vegetable crop zoning is underdeveloped. As a result, the assortment of recognized varieties and hybrids of carrot has long been outdated and is not replenished with new items. As part of the research work of the Federal State Budgetary Educational Institution of Higher Education "BGPU" at its agrobiological station, the specialists perform testing and assessment of various vegetable crops, including carrot. The purpose of the study is to identify high-yielding varieties of garden carrots suitable for cultivating in the agricultural and climatic conditions of the south of the Amur Region. The field trial was performed in accordance with the methods developed by B.A. Dospekhov (1985) and the state variety testing of agricultural crops described in "Vegetable and Cucurbit Crops, Potato, and Fodder Root Crops" (1956). The researchers applied agricultural technology that is commonly used in the region. Fifteen carrot samples of foreign selection were the object of the study. The hybrid F1 Abaco that had been grown at the agrobiological station for a long time was set as a standard. The vegetative period of the studied varieties under the regional conditions is 92-110 days. Nanco F1 and Sylvano F1 showed high yields, producing 41.0 and 47.0 tons of marketable roots per ha, with an average root weight of 110.1 and 120.9 g, respectively. The marketability of harvested root crops was 89.0% for Nanco F1 and 94.0% for Sylvano F1. We recommend vegetable growers in the region to establish a cultivation conveyor for garden carrots using the mid-early Presto F1 hybrid for sale in an early bunch and high-yielding F1 hybrids Nanco and Sylvano for fall use.

12 samples of carrot were analyzed for biochemical components in roots. 5 genotypes with high content of vitamin C, β-carotene, and total sugar were selected as genetic sources of high biochemical components.

The study of the dynamics of plant growth and yield of vegetable crops (carrot variety Absheron winter (Daucus carota subsp. sativus (Hoffm.) Schьbl.) and radish variety Virovsky white (Raphanus sativus var.radicula Pers.)) was conducted in the field conditions after presowing exposure to different temperatures: I option – sowing of seeds exposed to low temperatures (for 15 days the swollen for 24 hours seeds were kept at a temperature of 0±1°С); Option II - sowing of seeds exposed to variable temperatures (for 5 days, the swollen for 24 hours seeds were exposed to variable temperatures of + 20°C (8 hours) and 0±1°C (16 hours) and then 10 days at a temperature of 0±1°C; K1 – sowing dry seeds; K2 – sowing soaked seeds. The impact on the seeds of low and variable temperatures caused an increase in growth processes, both in radish and carrot. Both studied crops showed a tendency to increase the yield to a greater extent when exposed to swollen seeds with variable temperatures. Thus, the average weight of radish crops exceeded the control variant by 47.1% and carrots by 27.6%. The yield of root crops per m2 increased by 36.4% for radish and 30.0% for carrot. To increase the productivity of vegetable crops, we recommend using the studied methods of pre-sowing seed treatment in practice.

The developed technology, regulatory and technical documentation allowed to produce 3-5-kg packages of sterilized vegetables: potatoes, beets, carrots and cabbage, which are in great demand in the social nutrition (the army, schools, hospitals). The use of packaging for products of composite materials allows to reduce the amount of required storage space.