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.

The demand of sorghum is increasing since sorghum has significant and positive role in promoting nutrition and health of human beings; however, sorghum cultivated by farms is mostly a native variety having low genetic purity and low production, so it is necessary to improve the variety. Accordingly, the National Institute of Crop Science (NICS) developed “Donganme” that is non-glutinous and functional sorghum having antioxidant activity with higher yield potential. “Donganme” is the variety cultivated in 2012 through the breeding by the separation method from the foundation stock of ‘CS-4 LOCAL COLLECTION’ parceled out from the National Agricultural Genetic Resources Center. “Donganme” is a medium maturing variety, which takes the average of 71 days from the sowing date to the heading date, and the average of 120 days to the harvest. It has the culm length of 138 cm; the egg-shaped spikelets; dark red seeds, which are redder than those of the native variety, “Hwanggumchal.” Since the number of the ears is 3 per plant, the advantage of tillers is mature at the same time; The average quantity of the regional adaptation test is 3.1 MT/ha, and it means the high-yielding ability. In addition, Donganme contains various functional components including polyphenols, flavonoids, etc.; its antioxidant activity is 42.0 mgTE/g and 30% higher than that of “Hwanggumchal.” Unpolished grain’s thousand-kernel weight is 26.8 g; the weight per plant is as heavy as 33.6 g; the lodging is stronger than that of “Hwanggumchal”. Hwanggumchal has been cooked simply with rice due to its glutinous property, however, Donganme can be used more widely for processed food, such as bread, crackers, noodles, etc., due to its non-glutinous property. Moreover, its antioxidant activity can enhance the quality of those processed food.