The changes in volatiles during postharvest storage of three peach cultivars (JC, ZYP9 and ZY8) were tracked under two temperature conditions (25 °C and 4 °C). Overall volatile content significantly decreased during storage over time, specifically with a marked decrease in ester levels, while the relative proportions of alcohols, aldehydes, and ketones increased during cold storage. These changes in volatile composition revealed three distinct storage stages across the cultivars, with the middle stage marking a critical turning point in volatile flavor quality. Among the cultivars, ZYP9 and ZY8 exhibited better adaptability to cold storage than JC. The reduction in key esters, coupled with the increase in alcohols and aldehydes, led to altered aroma profiles and the development of off-flavors in cold-stored peaches. Overall, this study provides valuable insights into the dynamic changes in flavor volatiles during postharvest storage and contribute to a deeper understanding of aroma quality in stored peaches.

Due to its ornamental and medicinal value, pear flower has been historically loved and used in China. However, the current understanding of their odor-active compounds and aroma profiles is rather limited. This work aimed to evaluate and compare the overall aroma profile of pear flowers; the volatiles in flowers of seven pear cultivars (Anli, Bayuesu, Golden, Brown peel, KorlaXiangli, Lyubaoshi, Xizilü) were analyzed using solid-phase microextraction–gas chromatography-mass spectrometry (SPME-GC-MS). A total of 93 volatile compounds were identified and quantified within the amount of volatiles in the range of 62.7–691.8 μg kg⁻¹ (FW) and showed high and significant variability in different cultivars. Anli and Brown peel flowers showed a relatively higher volatile abundance, while KorlaXiangli flowers were significantly lower than other cultivars. Although the composition of volatiles depended on the existence of different chemical classes, the odor activity values (OAVs) and odor descriptions showed some aldehydes were part of their main peculiarities and were considered as the basic active odorants that presented strong intensity of citrus and floral odor. Moreover, multivariate analysis showed the pear flower of different cultivars could be arranged in different clusters by the identified odorants. This study provides first-hand knowledge regarding pear flower aroma profiles, and that the cultivar differences were critical for the overall pattern.

Blood flesh is a key fruit trait in peaches (Prunus persica) and can be attributed to the accumulation of anthocyanins. The roles of long non-coding RNAs (lncRNAs) have been highlighted by multiple studies in regulating fruit ripening, anthocyanin accumulation, and abiotic stress responses in many flowering plants. Such regulatory functions of lncRNAs in Prunus persica, nonetheless, have not been reported. In this research, we sequenced and analyzed the complete transcriptome of C3-20 (a blood-fleshed peach) fruit at four developmental stages. Analyses of the correlated genes and differentially expressed lncRNA target genes helped to forecast lncRNAs’ possible functions. The RNA-seq data were generated using high-throughput sequencing. In total, 17,456 putative lncRNAs, including 4,800 intergenic lncRNAs, 2,199 antisense lncRNAs, and 10,439 intronic lncRNAs were discovered, of which 4,871 differentially expressed lncRNAs (DE-lncRNAs) were annotated in the fruit developmental processes. The target genes of these DE-lncRNAs and their regulatory relationship identifying 21,795 cis-regulated and 18,271 trans-regulated targets of the DE-lncRNAs were in a similar way predicted by us. The enriched GO terms for the target genes included anthocyanin biosynthesis. Flavonoid biosynthesis and plant hormone signal transduction were also included in the enriched KEGG pathways. Co-expression network construction demonstrated that the highly expressed genes might co-regulate multiple other genes associated with auxin signal transduction and take effect in equal pathways. We discovered that lncRNAs, including LNC_000987, LNC_000693, LNC_001323, LNC_003610, LNC_001263, and LNC_003380, correlated with fruit that ripened and could take part in ethylene biosynthesis and metabolism and the ABA signaling pathway. Several essential transcription factors, such as ERFs, WRKY70, NAC56, and NAC72, may in a similar way regulate fruit ripening. Three DE-lncRNAs, XLOC_011933, XLOC_001865, and XLOC_042291, are involved in UV-B-induced anthocyanin biosynthesis and positively regulating UVR8 and COP10, were identified and characterized. Our discovery and characterization of XLOC_011933, XLOC_001865, and XLOC_042291 provide a more precise understanding and preliminarily establishes a theoretical framework for UV-B-induced flesh anthocyanin biosynthesis. This phenomenon might encourage more in-depth investigations to study the molecular mechanisms underlying peach flesh coloring.

Peach (Prunus persica L.) is an ancient fruit tree that originated from China. It is the climacteric fruit belonging to genus Prunus in family Rosaceae. Ethylene, which is produced during ripening, accelerates fruit softening, and therefore peaches cannot be stored for a long time. To study the mechanism of fruit late ripening, transcriptome analysis of the fruit of a late-ripening mutant of ‘Jinghong’ peach was performed to identify genes and pathways involved in fruit late ripening. A total of 1805, 1511, and 2309 genes were found to be differentially expressed in W2_vs_M1, W3_vs_M2, and W3_vs_M3, respectively. Functional enrichment analysis of the differentially expressed genes showed they were related to carotenoid biosynthesis, starch and sucrose metabolism plant hormone signal transduction, flavonoid biosynthesis, and photosynthesis. The expression trends of ripening-related genes that encode transcription factors and plant hormone signal transduction-related genes that encode enzymes were similar. It will help to elucidate the transcriptional regulatory network of fruit development in the spontaneous late-ripening mutant of ‘Jinghong’ peach and provide a theoretical basis for understanding the molecular regulatory mechanism of fruit ripening.

The peach landrace ‘Liuyefeitao’ exhibits the unique reproductive trait of self-compatibility combined with cross-incompatibility, contrasting with typical Prunus species in this way. In preliminary studies involving controlled pollination assays, we showed complete pollen tube arrest in cross-pollinated styles, whereas self-pollination enabled full tube elongation. S-genotyping identified a homozygous S₂S₂ genotype with intact S₂-RNase but a truncated PpSFB2 due to a frameshift mutation. Transcriptome profiling of the styles revealed 7937 differentially expressed genes (DEGs) between self- and cross-pollination treatments, with significant enrichment in plant MAPK signaling, plant–pathogen interactions, and plant hormone signaling transduction pathways (|Fold Change| ≥ 2, FDR < 0.01). Notably, PpSLFL3 (a pollen F-box gene) showed down-regulation in cross-pollinated styles, as validated by means of qRT-PCR. Protein interaction assays revealed direct binding between PpSLFL3 and S₂-RNase via Y2H and BiFC analysis, suggesting its role in mediating SCF complex-dependent degradation. We propose that insufficient PpSLFL3 expression during cross-pollination disrupts SCF ubiquitin ligase complex-mediated degradation of non-self S₂-RNase, leading to the toxic degradation of RNA in pollen tubes by S₂-RNase. This mechanism is mechanistically similar to unilateral reproductive barriers in Solanaceae but represents a novel regulatory module in Rosaceae. Our findings provide critical insights into the evolution of cross-incompatibility systems and molecular breeding strategies for Prunus species.