The<i>Di2/pet</i>Variant in the<i>PETALOSA</i>Gene Underlies a Major Heat Requirement-Related QTL for Blooming Date in Peach [<i>Prunus persica</i>(L.) Batsch]

Abstract Environmental adaptation of deciduous fruit trees largely depends on their ability to synchronize growth and development with seasonal climate change. Winter dormancy flower buds is a key process prevent frost damage ensure reproductive success. Temperature crucial environmental stimulus influencing the timing flowering, only occurring after fulfillment certain temperature requirements. Nevertheless, genetic variation affecting chilling or heat-dependent release still remains unknown. In this study, major QTL able delay blooming date in peach by increasing heat requirement was finely mapped three segregating progenies, revealing strict association variant (petDEL) PETALOSA gene, previously shown also affect morphology. Analysis genome-edited tobacco plants provided further evidence potential PET variations flowering time. Potential applications petDEL for improving phenological traits are discussed.