This invention relates to the genetics of gender discrimination in the dioecious date palm. Methods of the present invention involve analyzing DNA or RNA from a date palm plant, tissue, germplasm, or seed for the presence of (i) a nucleic acid sequence or genotype that identifies the sex of the plant, tissue, germplasm, or seed or (ii) a molecular marker in linkage disequilibrium with the nucleic acid sequence or genotype. Also disclosed are kits for selecting male and female date palm plants prior to flowering, methods of breeding a date palm plant, and a method of planting a date palm seed of a known sex.