The researchers studied the relationship between grain yield and its components in different types of maize plants. They found that certain traits in maize are more heritable and less affected by the environment, making them good indicators of grain yield. By looking at genetic correlations, breeders can indirectly select plants for higher yield. The study involved two trials with the same maize genotypes grown in different nitrogen levels. They discovered that at lower nitrogen levels, grain yield was linked to plant height, ear length, and other factors, while at higher nitrogen levels, it was connected to different traits like ear diameter and kernel weight.