Inbreeding is used very much in the most allogamy crops in the breeding and agricultural production today. Inbreeding increases dominant signs and eliminates recessive genes. Due to inbreeding we can find new forms in the populations of allogamy crops which are useful for humanity because they have recessive signs. Freely crosses populations have such signs in hidden form.

The main importance of inbreeding is creation of homozygous generation in a short time. An increasing productivity of plant on the basis of heterosis effect is a result of hybridization of inbred lines.

The problem of complex and comprehensive study of biological and selection signs of hemp (Cannabis sativa L.) inbred lines is very important. These studies were not conducted in full because of cytoplasmic male sterility is not found and inbred lines were not used to create heterotic hybrids.

Researchers have described different types of inbreeding effects on height of the stems of hemp plant. The height of the stems of hemp inbred lines were studied by Fruvirth C., Gorshkova L.M., Migal M.D., Laiko I.M., Sytnyk V.P., Vyrovets V.G., Kaplunova R.I. Dioecious and monoecious forms of hemp were studied.

We analyzed generations from self-pollination varieties of hemp Zolotonoshskaya 15. According to the information was received by us, some families have differentiation of plant height stem. This problem demands special study. The height of the stems is very important breeding sign. Harvest of stems depends on the height. Sign of stem height is positively correlated with technical height stems, which determines the yield of long fiber. Also a sign of stem height is positively correlated with the size of the inflorescence, which depends on seed yield.

The study was conducted from 2008 to 2010 on the basis of Research Station of Bast Crops of the Institute of Agriculture North-East NAAS of Ukraine (Glukhiv, Sumy region). The plants of monoecious hemp varieties of South eco-geographic type Zolotonoshskaya 15 were self-fertilization. It was done in a glass house. We used individual isolators which were made from agro fiber. Generations were studied by us. Area power of plants was 30 x 5 cm. Height was measured on living plants. Genetic and statistical parameters such as the arithmetic mean, error of the sample mean, minimum, maximum, fashion, median, average deviation, coefficient of variation, asymmetry, excess were installed..

The studies established the fact of differentiation of plant height into separate generation inbred hemp plants for example of a variety Zolotonoshskaya 15.

Normal distribution characteristics of plant height (E = 0.0) has all original forms (І0 Zolotonoshskaya 15). The coefficient of variation and error of sample mean increases in plants І1. In 2009, the height of the stems was from 128.5 to 185.9 cm (in the original form it was 160.9 cm). In 2010, the height of the stems was from 162.0 to 186.3 cm (in the original form it was 188.2 cm).

There is a differentiation of individuals in the low and tall plants in І1 Zolotonoshskaya 15 in many families. There are lines with different variability characteristics of the investigated parameters of asymmetry and excess of the empirical distribution of the curve, such as:

positive asymmetry and negative excess (A = 0,6, E = –0,7 in family number 771);

negative asymmetry and negative excess (A = –0,2, E = –0,6 in family number 772; A = –0,1, E = –1,6 in family number 788; A = –0,6, E = –0,2 in family number 636; A = –0,2, E = –1,0 in family number 640; A = –0,1, E = –1,2 in family number 652);

negative asymmetry and positive excess (A = –1,1, E = 2,1 in family number 799; A = –0,6, E = 0,4 in family number 659);

zero asymmetry and negative excess;

negative asymmetry and zero excess.

There was low and high value plant 1 : 1 in family number 788, 640 and 652.

Genetic and statistical indicators point to the complex genetics of plant height signs as a quantitative sign.

SLP 470 inbred lines were based on the variety of monoecious hemp Zolotonoshskaya 15. It has a valuable breeding signs such as:

overall height of the stems – 221.6 cm,

harvest of the stems – 1230 g/m²,

technical length – 182.9 cm,

fiber content – 28.2%,

weight of thousand seed – 17.1 g,

drug compounds are absent.

There is the possibility of creation of inbred lines for a certain level of signs. There is also a possibility to these inbred lines to use in plant breeding through the use of statistical methods to assess variability and to establish whether the empirical frequency distribution of genotypes theory. Inbreeding and its extreme form of self-pollination is important analyzers of complex population of cross-pollination species of cultivated hemp.

Key words: hemp, inbreeding, self-fertilization, inbred lines, plant height, asymmetry, excess, breeding.