CRISPR (short for “Clustered Regularly Interspaced Short Palindromic Repeats”) is a technology that research scientists use to selectively modify the DNA of living organisms. CRISPR was adapted for use in the laboratory from the naturally occurring genome-editing systems found in bacteria. In this work, we reviewed the methods used to introduce CRISPR/Cas-mediated genome editing into fruit species, as well as the impacts of the application of this technology to activate and knock out target genes in different fruit tree species, including on tree development, yield, fruit quality, and tolerance to biotic and abiotic stresses. The application of this gene-editing technology could allow the development of new generations of fruit crops with improved traits by targeting different genetic segments or even could facilitate the introduction of traits into elite cultivars without changing other traits. However, currently, the scarcity of efficient regeneration and transformation protocols in some species, the fact that many of those procedures are genotype-dependent, and the convenience of segregating the transgenic parts of the CRISPR system represent the main handicaps limiting the potential of genetic editing techniques for fruit trees. Finally, the latest news on the legislation and regulations about the use of plants modified using CRISPR/Cas systems has been also discussed.

This study characterizes the metabolomic profiles of three reference apricot cultivars (‘Bergeron’, ‘Currot’, and ‘Goldrich’) using ¹H NMR spectroscopy and untargeted UPLC-QToF MS/MS to support plant breeding by correlating metabolomic data with fruit phenotyping. The primary objective was to identify and quantify the key metabolites influencing fruit quality from a nutraceutical perspective. The analysis revealed significant differences in primary and secondary metabolites among the cultivars. ‘Bergeron’ and ‘Goldrich’ exhibited higher concentrations of organic acids (109 mg/g malate in ‘Bergeron’ and 202 mg/g citrate in ‘Goldrich’), flavonoids such as epicatechin (0.44 mg/g and 0.79 mg/g, respectively), and sucrose (464 mg/g and 546 mg/g), contributing to their acidity-to-sugar balance. Conversely, ‘Currot’ showed higher levels of amino acids (24.44 mg/g asparagine) and sugars, particularly fructose and glucose (79 mg/g and 180 mg/g), enhancing its characteristic sweetness. These findings suggest that metabolomic profiling can provide valuable insights into the biochemical pathways underlying apricot quality traits, aiding in the selection of cultivars with desirable characteristics. The integration of phenotyping data with ¹H NMR and UPLC-QToF MS/MS offers a comprehensive approach to understanding apricot metabolomic diversity, crucial for breeding high-quality, nutritionally enriched fruits that meet market demands.

The main objective of this study was to monitor apricot development and ripening through gene expression analysis of key candidate genes using the RT-qPCR technique. Eight apricot cultivars were selected to analyze phenological and genetic patterns from pre-ripening stages through to postharvest. In addition, 19 selected genes were analyzed in the contrasting cultivars ‘Cebas Red’ and ‘Rojo Pasión’ in different stages (two preharvest stages S1 and S2, one harvest stage S3, and two postharvest stages S4 and S5). This pool of genes included genes related to fruit growth and ripening, genes associated with fruit color, and genes linked to the fruit’s nutraceutical aspects. Among the studied genes, Polygalacturonase (PG), Pectin methylesterase (PME), Aminocyclopropane-1-carboxylate synthase (ACS), and Myo-inositol-1-phosphate synthase (INO1) were directly related to fruit maturation and quality. Significant differential expression was observed between the cultivars, which correlated with variations in firmness, shelf life, and sensory characteristics of the apricots. ‘Rojo Pasión’ displayed high levels of PG, associated with rapid maturation and shorter postharvest shelf life, whereas ‘Cebas Red’ exhibited lower levels of this gene, resulting in greater firmness and extended shelf life. Genes CCD4, CRTZ, and ZDS, related to carotenoids, showed varied expression patterns during growth and postharvest stages, with higher levels in ‘Rojo Pasión’. On the other hand, Sucrose synthase (SUSY) and Lipoxygenase (LOX2) were prominent during the postharvest and growth stages, respectively. Additionally, GDP-L-galactose phosphorylase (VTC2_5) was linked to better postharvest performance. This research provides valuable insights for future breeding initiatives aimed at enhancing the quality and sustainability of apricot cultivation.

The methods used to introduce CRISPR (Clustered Regularly Interspaced Short Palindromic Repeats)/Cas-mediated genome editing into fruit species, as well as the impacts of the application of this technology to activate and knock out of target genes in different fruit trees species including tree development, yield, fruit quality, and tolerance to biotic and abiotic stresses have been firstly described in this review. The application of this gene editing technology could allow the development of new generations of fruit crops with improved traits by targeting different genetic segments or even could facilitate the introduction of traits in elite cultivars without changing other traits. However, at this moment, the scarcity of efficient regeneration and transformation protocols in some species, the fact that many of those procedures are the genotype-dependent or the convenience of segregating the transgenic parts of the CRISPR system represent the main handicaps limiting the potential of genetic editing techniques for fruit trees. Finally, latest news on the legislation and regulations about the use of plants modified through CRISPR/Cas systems has been also discussed.

Assessing and determining genetic diversity in rose species is a crucial step for conservation efforts, the establishment of a core collection, and the development of new varieties. This study represents the first investigation of genetic diversity among various rose species at different ploidy levels in Tunisia, with the aim of elucidating the genetic structure of the Rosa genus. It encompasses both spontaneous and cultivated accessions, featuring local and introduced species recognized for their adaptability, ornamental value, and fragrance. A total of 114 accessions representing eight rose species were collected. Significant genetic diversity was assessed using seven SSR markers, yielding an average of 21 alleles per locus and a PIC value ranging from 0.882 to 0.941. The results identified 343 phenotypic alleles across the seven primers, with 72 for the primer RhE2b (LG6), 55 for H10D03 (LG7), and 54 for RhB303 (LG2). One key finding was that most perfumed rose accessions (R. damascena Mill. and R. centifolia L.) are distinct from the other rose accessions, indicating a unique genetic pool for these roses. Another important finding was that the Tunisian accessions of ‘Rose of Ariana’ were closely related to R. centifolia accessions, commonly known as the ‘Rose of May’ from Grasse, France. To clarify the phylogeny of this species or subspecies, further molecular studies are warranted. Additionally, nomenclature confusion was identified between R. sempervirens L. and R. canina L. in the northwestern region of Tunisia, indicating that all wild accessions correspond to R. sempervirens.

Prunu s sero tina Ehrh., commonly known as capuli, represents a valuable genetic resource for breeding programs aimed at improving fruit quality. This study presents the in situ morpho-agronomic and molecular characterization of sixty capuli accessions that were collected in situ and are currently conserved in the INIAP-Ecuador National Germplasm Bank. Thirty quantitative and qualitative traits were evaluated, supported by principal component analysis (PCA) and hierarchical clustering to explore phenotypic structure. ANOVA revealed significant regional differentiation in key fruit traits, including fruit weight ( p = 0.000015), equatorial and polar fruit diameter ( p = 0.0036 and p = 0.0015), epidermis weight ( p = 0.0065), and seed diameter ( p = 0.011), as well as floral traits such as flower diameter ( p = 0.0002) and sepal width ( p = 0.0018). Tukey’s post hoc comparisons indicated that the strongest contrasts occurred between Cotopaxi–Tungurahua and Chimborazo–Tungurahua. Molecular analysis using five SSR primer pairs (AB, PceGA34, PS12A02, Pchpgms3, and Pchgms2) revealed high genetic variability, with an average polymorphism information content (PIC) of 0.792. Population structure analysis (STRUCTURE and PCoA) identified three major genetic groups. The results demonstrate considerable phenotypic and genetic diversity, providing essential insights for breeding strategies aimed at developing superior capuli cultivars in Ecuador.