Traditional farmers' varieties of maize have a lot of genetic diversity that can be useful for improving the nutritional value of the crop. Researchers in Nigeria studied 156 different types of maize in different conditions to see which traits were most important for increasing grain yield. They found that traits like plant and ear aspects, ear height, number of seeds per ear, and ear length were crucial for improving yield, especially under drought conditions. These findings can help breeders choose the best maize varieties to grow in different environments and increase the overall productivity of the crop.