Assessment of the Combinational Ability of Inbred Winter Rye Lines in Plant Height.

The aim of this research was to evaluate the general and specific combinational ability of inbred winter rye lines in plant height and to identify relatively short-stemmed combinations. The starting material for the crossing was 22 homozygous rye lines carrying sterile cytoplasm of the Pampa type. The male fertile homozygous lines mf H‑1423, mf H‑1247, mf H‑732, and mf H‑842 were used as testers, in which the plant height was 122, 120, 102, and 100 cm, respectively. Test crosses were carried out in isolated plots according to the topcross scheme. A total of 88 simple F1 hybrids were produced. These were tested on plots of 8.0 m² in three repetitions. The average height of plants in F1 hybrids was 129 cm and ranged from 114 to 145 cm. The hybrids with the mf H‑732 and mf H‑842 testers turned out to be the shortest-stemmed, and the tallest ones were those with the mf H‑1423 tester. Both general (GCA) and specific (SCA) combinational abilities made a significant contribution to the variance of the plant height trait. The genotypes ms H‑422 and ms H‑1179 had a significantly higher GCA compared to other lines, while ms H‑700 and ms H‑1058 had a lower GCA. Among the testers, the high-stemmed mf H‑1423 and mf H‑1247 lines had a significantly high GCA, and the short-stemmed mf H‑732 and mf H‑842 testers had a significantly low GCA. Combinations involving short-stemmed testers made up a group of the shortest-stemmed hybrids, in which plant height varied from 114 to 120 cm. It has been shown that lines with low effects are of great value for practical breeding not only for GCA, but also for SCA. The ms H‑700 line is of interest, which simultaneously combines low GCA and SCA. [ABSTRACT FROM AUTHOR]