Selection of Inbred Lines of Alfalfa for Creating Synthetic Varieties

Abstract

The importance of breeding inbred lines of alfalfa with high combining ability has been shown for using as initial components of newly created synthetic varieties with adjustable genetic basis of the intrapopulational heterosis effect in case of panmixia. The article is dedicated to the following issues of the general scheme of selection process: Self-fertility of 250 heterogeneous genotypes that consist of 10 varieties of alfalfa population was studied and 50 elite genotypes were selected; based on the indicators of the level of self-fertility, 313 genotypes of alfalfa form were transferred from J₂ to J₃ and 100 elite genotypes with the level of self-fertility above 40% were selected for assessing the general combining ability; genetic diversity with variation from 0.29 to 0.36 unit was established. Absolute homozygosity was not achieved even in highly inbred lines. Genomes of inbred lines had partial similarity both in the spectra of reserve proteins of seeds and in amplifiable DNA fragments of the SSR markers type; By the general combining ability, out of 1,240 polycross descendants from inbred lines of alfalfa, 75 lines with the level of competitive heterosis of 30 to 50% were selected. Promising inbred lines of alfalfa C-21/14 and K-13/07 were reproduced by the method of micropropagation in vitro. They are of interest for breeding synthetic varieties as parent components.