; then, beginning in the F0, the best individuals in the best families can be selected. Replicated testing of families can begin in the F0 or F0 generation to improve the effectiveness of selection for traits with low heritability. At an advanced stage of inbreeding (i.e., F0 and F0), the best lines or mixtures of phenotypically similar lines are tested for potential release as new varieties. Mass and recurrent selections can be used to improve populations of either self-or cross-pollinating crops. A genetically variable population of heterozygous individuals is either identified or created by intercrossing several different parents. The best plants are selected based on individual superiority, outstanding progeny, or excellent combining ability. The selected plants are intercrossed to produce a new population in which further cycles of selection are continued. 