The researchers studied different types of cucumber plants to see which combinations produced the most fruit. They found that some combinations of plants had better yields than others, with 'Zeina' and 'Calypso' being the best pair for total fruit yield. They also discovered that certain plants had more influence on the traits of the offspring, suggesting that some traits are passed down more strongly from parent to child. Overall, 'Beit Alpha' and 'Straight 8' were the best plants for producing high-yielding offspring.