Towards the Identification of Useful Genes for Prunus Breeding

The genus Prunus (Rosaceae) includes species of enormous economic importance. Major Prunus crop species originated in Northern temperate regions between Eastern Europe and East Asia, but nowadays are cultivated worldwide for their edible fleshy mesocarp (e.g. peaches, plums, apricots, and cherries), for their edible seeds (e.g. almonds, apricots, etc) and for ornamental purposes (e.g. P. mume, P. serrulata or P. × yedoensis in the Japan cherry blossom festivals, P. persica, etc. ). The Prunus germplasm shows a wide genetic and phenotypic variability among cultivated species and wild crop relatives that constitutes the necessary basis for efficient breeding. For instance, significant diversity can be found in ploidy levels and genome contents, flowering date, and self-(in)compatibility, pathogen resistance, ecological requirements, etc. Thus, conventional breeding in stone fruits has been mainly focused on fruit yield and quality, pest and disease resistance, and environmental adaptation. Similar to other woody species, stone fruit breeding is hampered by a long juvenile phase, high space requirements, and time-consuming phenotyping methods needed to release new varieties. In addition, the inefficient regeneration systems generally limit stable genetic transformation procedures with a few exceptions (e.g hexaploid plum). In spite of these limitations, Prunus breeding has gained momentum over the past two decades since the development of molecular markers that facilitated the study of genetic variability and gene/QTL mapping. Currently, high-throughput DNA sequencing technologies make possible to tackle new basic and applied studies. Peach genome (the Prunus reference genome) is publicly available since 2010 and seven additional Prunus species genomes are accessible at the NCBI database (P. armeniaca, P. avium, P. dulcis, P. mume, P. persica and P. yedonensis). Moreover, the Genome Database for Rosaceae (GDR) holds genomes from other five Prunus species as well as a wide range of genetic and breeding resources. As a whole, these tools are paving the way for studying in depth the genetic control of relevant agronomic traits, including environmental requirements considering global warming, reproductive biology aspects, resistance, etc., and ultimately for identifying the underlying genes.

This Research Topic will highlight recent progress, key advances, and future perspectives in Prunus genus for crop improvement by breeding, -omics, and biotechnology-based approaches.

We welcome the submission of high-quality Original Research, Review, Mini-Review, Opinion, and Perspective papers on the following topics:
• Advances in Prunus breeding methods
• Advances in genome sequencing, development of markers for traits of interest, and comparative genomics
• Advances in identification of QTLs, fine mapping and cloning of candidate genes
• Advances in knowledge of the genetic control of biotic and abiotic stress affecting Prunus spp
• Advances in knowledge of the genetic control of agronomic and fruit quality traits
• Screening and development of genetic resources to respond to climate change
• Genetic characterization of mutants