A CsYcf54 variant conferring light green coloration in cucumber

The color of cucumber fruits, which is mainly determined by the content of chlorophylls, largely influences consumers' preference. A recessive mutant showing light green fruits and leaves was identified in an M-2 population derived from ethylmethane sulfonate mutagenized elite cucumber line 406. By MutMap analysis of bulked F-2 DNA with normal and mutant phenotype, respectively, the causative SNP co-segregating with the mutant phenotype was identified. The gene Csa6G133820, harboring the causative SNP, encodes an Ycf54-like protein that has recently been implicated in the cyclase step of chlorophyll biosynthesis. Subcellular localization showed that Csa6G133820 was localized in the chloroplasts, supporting its role in the chlorophyll biosynthesis. The light green mutant provides a novel locus for cucumber breeding.