Advances in Developmental Biology in Tree Fruit and Nut Crops

This reprint of the Special Issue “Advances in Developmental Biology in Tree Fruit and Nut Crops” brings together 16 diverse studies that illuminate how genetic, hormonal, and environmental factors shape the growth and productivity of key tree fruit and nut species. Several articles explore hormone-mediated processes, such as the role of exogenous abscisic acid in anthocyanin biosynthesis in blueberry leaves, the effects of gibberellic acid on Shine Muscat grapes, and the influence of endogenous hormones on seed hardness in pomegranate. Other contributions focus on molecular and genomic insights, including the characterization of the PpEXPs family in peach for fruit texture development, identification of laccase genes in grapevine under pathogen stress, and genome-wide analyses of the PYR/PYL/RCAR gene family in pomegranates. Germplasm diversity and phylogenetic relationships also feature prominently, highlighted by research on Caribbean breadfruit, almond S-RNase genotypes, and chloroplast genome profiling of “Qixiadaxiangshui” pear. Meanwhile, integrated transcriptomic and metabolomic approaches uncover stress responses in strawberry and blueberry, and shed light on photoprotective mechanisms in Torreya grandis. Further articles address flower-to-fruit ratios in olives, selective fruitlet retention in avocados, and lipoxygenase gene expression in sweet cherries. Together, these 16 papers offer a comprehensive perspective on the developmental biology driving innovations in tree fruit and nut crops.