Corn is a major cereal crop in Ukraine which provides feed and silage for livestock. Now corn is one of most profitable crops in agriculture production due to the introduction of new competitive hybrids and new agricultural technologies. For creation of such hybrids it is necessary to have initial material, in particular, inbred lines that require evaluation of economic-valuable traits. Correlations of these traits allow breeders to carry out selection of initial material on early stage of breeding with use of circumstantial evidence.
In our research was carried out analysis of inbred lines of corn by manifestation of economic valuable traits and identify the level of correlation coefficients between yield and the main traits which uses in analysis of harvest structure and indicators of general and specific combination ability.
According to the results of analysis of manifestation of the main economically-valuable traits and the determination of the correlation coefficient between them it was established that correlation coefficient between yield capacity and some elements of yield structure in inbred lines is positive and ranges from weak to strong depending on the year of research and traits (r = 0.33–0.81).
These data confirm that length of cob is closely related to the number of grains in the rows (r = 0.74-0.81). Since this indicator significantly influence to yield capacity than selection of lines with forks of larger size and diameter, and accordingly a large number of grains in the rows is important.
The height of attachment of the cob and the number of leaves on the main stem was observed slightly lower, but positive relationship (r = 0.65-0.61). Yield capacity and mass of cob was related by strong positive relation r = 0,74 in 2018 and medium – r = 0,47 – in 2017.
Reliable and stable connections of medium strength were found between the number of days from germination to flowering of cobs and full maturity (r = 0,52-0,77). This proves that in breeding for early ripeness, preference should be given to lines with early periods of flowering cobs. Attention deserve indicator of the height of attachment of the cob, this trait is associated with resistance to lodging of stem and suitability of corn for mechanized harvesting. Literature data points that optimal height of attachment of cob is 50–70 cm. It was established that height of attachment of low cob has significant medium correlation with quantity of leaves on main stem (r = 0,65-0,61) and yield capacity (r = 0,54-0,60).
One of important characteristic of yield considers mass of 1000 grains. Conducted research points on presence positive but not significant correlation (on 95% level) and in 2017–2018 reached an average (r = 0,49-0,43) level.
It was established that lines which were involved in scheme of dialeal crosses has strong differed from each other both on specific combination ability and it stability in different years. Most stable and high manifestation of specific combination ability on yield capacity provides lines Um 331 and Um 337 that give us possibility to use them as valuable components for creation of single high productive hybrids. Lowest indicators was fixed in Co125 (from -0,58 to -0,79). That is higher or lower value of specific combination ability in largely dependent from genotype of inbred lines and their specific reaction on condition of growing.
corn, inbred lines, mass of 1000 grains, yield, stability, adaptability