The present invention relates to an allele designated alpha-WOLF 15 which confers resistance to at least one Peronospora farinosa f. Sp. spinacea race, wherein the protein encoded by said allele is a CC-NBS-LRR protein that comprises in its amino acid sequence: a) the motif “MAEIGYSVC” at its N-terminus; and b) the motif “KWMCLR”; and wherein the LRR domain of the protein has in order of increased preference at least 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, 100% sequence similarity to SEQ ID No:10. The allele when homozygously present in a spinach plant confers complete resistance to Peronospora farinosa f. Sp. spinacea races pfs:1, pfs:2, pfs:3, pfs:4 and pfs:5, pfs:6, pfs:8, pfs:9, pfs:11, pfs:12, pfs:13, pfs:14, pfs:15, pfs:16 and isolates UA1014 and US1508, and confers intermediate resistance to pfs:10, and does not confer resistance to pfs:7.