The researchers studied different cowpea lines to see how much they varied in important traits like seed weight and number of pods. They found that there was a lot of variation among the lines, especially in traits related to yield. The study showed that the traits were mostly inherited from the parent plants, with high heritability for seed weight and moderate heritability for other traits like number of seeds per pod. This means that plant breeders can choose parent plants with desirable traits to improve cowpea crops.