Unraveling the mystery of auxin-promoting femaleness in cucurbits

The female flower gives rise to the fruit/seed and thus directly affects crop yield in unisexual plants. Both ethylene and auxin promote femaleness in cucurbits. However, how auxin regulates sex determination has been an open question over half a century. The recent publication identified auxin response factor <i>CsARF3</i> as a crucial player in auxin-promoting femaleness, and revealed a reciprocal relationship between auxin and ethylene during female flower determination.