The researchers studied how different combinations of barley plants can produce higher grain yields. They crossed 10 different types of barley plants and grew their offspring in three different planting times. They found that some crosses resulted in significantly higher grain yields, with some combinations showing better results than others. The crosses BHS 400 × PL 426, PL 426 × RD 2552, and BH 959 × RD 2552 were the most successful in producing high grain yields. This study suggests that these specific crosses have the potential for improving barley grain yield in the future.