Dr. Wadlington from the University of Illinois at Urbana-Champaign has developed a novel marker for the X-chromosome of spinach. This marker allows identification of YY spinach for the first time and can be used with Y-specific markers to accurately sex spinach. By identifying YY spinach breeders can grow an all XY generation of seeds, this enables the planting of all-male rows for hybrid crosses which should enhance crop yields. This is the first X-chromosome specific marker developed.