Reciprocal recurrent selection in sugarbeet

Abstract Sugarbeet root yield is conditioned by both additive and nonadditive types of gene action. The reciprocal recurrent selection breeding method is designed to aid in simultaneously selecting for both types of gene action and requires that plants be both crossed and selfed. For adaptation of this method to sugarbeet, some modification is necessary, because the sugarbeet is normally cross-pollinated and is very difficult to emasculate. Incorporation of the self-fertile gene, S f (dominant), and the male-sterile gene, a 1 (recessive), makes this method useful for sugarbeet improvement. The biennial nature of sugarbeet necessitates a five-year selection cycle. This method incorporates selection for root yield, sugar percent, disease resistance, and “O” type. The amount of material tested for combining ability for yield is reduced to a workable level by selecting for additive, highly heritable traits in the early phases. It can be adapted to any crop having self-fertile and male-sterile genes available in its gene pool.