국내 일대잡종 수수 품종개발을 위한 잡종강세 및 조합능력 검정

Heterosis and Combining Ability of F1 Hybrid Grain Sorghum in Korea (Sorghum bicolor L.)

A few inbred grain-sorghum varieties, developed and grown in Korea, have low productivity. Several hybrid cultivars have been demonstrated to be more productive and resistant to unfavorable environmental conditions than pure line varieties. However, very limited studies have been conducted on hybrid sorghum in Korea. Information on combining ability of Korean landraces based on parental materials is of great importance for increasing the productivity of sorghum through hybrid breeding programs. This study was conducted to determine the combining abilities of Korean sorghum landraces and cultivars. Two cytoplasmic male-sterile lines (A.Arg-1 and A03017) were crossed with 13 male-fertile lines to generate 26 experimental grain-sorghum hybrids. The hybrids were evaluated at two locations (Daegu and Miryang) in Korea in 2018. They were planted in three replications and standard agronomic practices were followed at both sites. There were significant (p=0.001) variations among genotypes for yield and secondary traits. For each trait, general combining ability (GCA) and specific combining ability (SCA) effects were estimated using the line-tester method. A positive heterosis for grain yield was observed in several hybrids. The A03017 × Sodamchal hybrids exhibited considerable heterosis of up to 54.1%. The lines 18AYT-S04 and Sodamchal displayed positive significant GCA effects for grain yield, and A03017 × Sodamchal crosses showed the highest positive SCA effects. The crosses, A.Arg-1 × 18OYT-S17, A.Arg-1 × Sodamchal and A.Arg-1 × 18OYT-S01 had high grain yields with waxy endosperms, and could be recommended for grain-sorghum breeding programs in Korea.