Biodiversity Evaluation and Preservation of Italian Stone Fruit Germplasm (Peach and Apricot) in Southern Italy

The Prunus genus encompasses a group of economically important and closely related crops, sharing an essentially common genome and, thereby, a high level of conserved and transferable microsatellite (SSR) loci. In Southern Italy, many of the local and/or neglected varieties are abandoned and at risk of extinction due to the high degree of urbanization and agricultural intensification, despite their value as genetic resources for crop improvement. This research aimed to genetically and morphologically characterize the traditional apricot (P. armenica) and peach (P. persica) germplasms collected in old family orchards. Most of the official descriptor categories were scored, thus revealing a rather high level of phenotypic variation in both collections. Genetic data allowed the discovery of diversity masked by morphological traits. Genotyping in 15 and 18 SSRs, eight of which were transferable across both species, showed an average polymorphic informativeness (PIC) of 0.44 and 0.59 for apricot and peach, respectively, and a total of 70 and 144 alleles. A reliable identification of each genotype was achieved, and the presence of possible mislabeling and/or erroneous denominations was solved. These results are encouraging for the valorization of the still poorly explored Italian Prunus germplasm, with significant economic consequences for bioresource conservation and management.

DNA Barcoding of Prunus Species Collection Conserved in the National Gene Bank of Egypt

Two intergenic spacers cpDNA barcoding regions were used to assess the genetic diversity and phylogenetic structure of a collection of 25 Prunus accessions. The trnH-psbA and trnL-trnF intergenic spacers were able to distinguish and identify only four Prunus species. The average aligned length was 316-352 bp and 701-756 bp for trnH-psbA and trnL-trnF, respectively. The overall evolutionary divergence was higher in trnH-psbA than trnL-trnF. The transition/transversion bias (R) recorded as 0.59 in trnL-trnF and 0.89 in trnH-psbA. The number of invariable sites, nucleotide diversity (Pi), and the average number of nucleotide differences (k) was higher in the trnH-psbA region. The trnL-trnF records was above the other region in the number of variable sites, number of singleton variable sites, and the parsimony informative sites. Phylogenetic relationships among the 25 accessions of Prunus species were investigated. Most of the different Prunus species clustered in a homogenized distribution in both regions, except for the plum (P. domestica) accession (African Rose) was assigned with the peach (P. persica) accessions. The two intergenic cpDNA trnH-psbA and trnL-trnF were able to distinguish and identify the four Prunus species accessions.

Different scales of gene duplications occurring at different times have jointly shaped the NBS-LRR genes in Prunus species

In this study, genome-wide identification, phylogenetic relationships, duplication time and selective pressure of the NBS-LRR genes, an important group of plant disease-resistance genes (R genes), were performed to uncover their genetic evolutionary patterns in the six Prunus species. A total of 1946 NBS-LRR genes were identified; specifically, 589, 361, 284, 281, 318, and 113 were identified in Prunus yedoensis, P. domestica, P. avium, P. dulcis, P. persica and P. yedoensis var. nudiflora, respectively. Two NBS-LRR gene subclasses, TIR-NBS-LRR (TNL) and non-TIR-NBS-LRR (non-TNL), were also discovered. In total, 435 TNL and 1511 non-TNL genes were identified and could be classified into 30/55/75 and 103/158/191 multi-gene families, respectively, according to three different criteria. Higher Ks and Ka/Ks values were detected in TNL gene families than in non-TNL gene families. These results indicated that the TNL genes had more members involved in relatively ancient duplications and were affected by stronger selection pressure than the non-TNL genes. In general, the NBS-LRR genes were shaped by species-specific duplications, and lineage-specific duplications occurred at recent and relatively ancient periods among the six Prunus species. Therefore, different duplicated copies of NBS-LRRs can resist specific pathogens and will provide an R-gene library for resistance breeding in Prunus species.

Potential Application of Prunus armeniaca L. and P. domestica L. Leaf Essential Oils as Antioxidant and of Cholinesterases Inhibitors

The aim of this work is to investigate the in vitro acetylcholinesterase (AChE) and butyrycholinesterase (BChE) inhibitory activities of essential oils obtained by hydrodistillation from the leaves of Prunus armeniaca and P. domestica in relation to their composition, analysed by Gas Chromatography–Flame Ionization Detector (GC-FID) and Gas Chromatography-Mass Spectrometry (GC-MS) analyses, at different times. Moreover, considering the role of free radicals in the progression of neurodegenerative disorders, the antioxidant properties of essential oils were investigated by using, 2’-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid) (ABTS), 2,2-diphenyl-1-picrylhydrazyl (DPPH), and β-carotene bleaching tests. The relative antioxidant capacity index (RACI) was used to achieve more comprehensive comparison between analysed antioxidant effects of essential oils. P. armeniaca oils were more active than P. domestica oils against AChE. Against BChE, the most active was the essential oil from P. domestica leaves collected in August with an IC₅₀ value of 95.80 μg/mL. This oil exerted the highest inhibitory activity of lipid peroxidation with IC₅₀ values of 11.15 and 11.39 μg/mL after 30 and 60 min of incubation, respectively. All samples demonstrated a remarkable ABTS radicals scavenging activity, with IC₅₀ values in the range 0.45–0.57 μg/mL in comparison to the positive control, ascorbic acid.

Amelioration of testosterone induced benign prostatic hyperplasia by Prunus species

ETHNOPHARMACOLOGICAL RELEVANCE

Benign prostatic hyperplasia (BPH) is a common urological disorder of men. The ethnomedicinal use of an African plant Prunus africana (Hook.f.) Kalkman (Pygeum) in treating men's problems made it a popular remedy all over the globe for the treatment of BPH and related disorders. However, rampant collections made from the wild in Africa have pushed the plant to Appendix II of CITES demanding conservation of the species.

AIM OF THE STUDY

In the present study, the aim was to unearth the protective effect of bark of different species of Prunus against BPH. The five selected Indian plants of family Rosaceae viz. Prunus amygdalus Stokes, Prunus armeniaca L., Prunus cerasoides Buch.-Ham. ex D. Don, Prunus domestica L. and Prunus persica (L.) Batsch were evaluated against P. africana (Hook.f.) Kalkman for a suitable comparison of efficacy as antiBPH agents.

MATERIALS AND METHODS

The antiBPH activity was evaluated in testosterone (2mg/kg/day, s.c, 21 days) induced BPH in Wistar rats. The parameters studied were body weights; histopathological examination, immunohistochemistry (PCNA) and biochemical estimations of the prostate; supported by prostatic index, testicular index, creatinine, testosterone levels; antioxidant and anti-inflammatory evaluation. The study also included chemical profiling using three markers (β-sitosterol, docosyl ferulate and ursolic acid) and estimation of β-sitosterol content through GC.

RESULTS

The Prunus species showed the presence of all the three markers in their TLC fingerprint profile and maximum amount of β-sitosterol by GC was observed in P. domestica. Interestingly, all the species exhibited significant amelioration in testosterone induced parameters with P. domestica showing the most encouraging effect as indicated from histopathological examination, immunohistochemistry and biochemical studies. The Prunus species further showed remarkable anti-inflammatory and antioxidant activity signifying their role in interfering with various possible factors involved in BPH.

CONCLUSIONS

These findings are suggestive of a meaningful inhibitory effect of testosterone induced BPH by the bark of different species of Prunus in the order of P. domestica, P. persica, P. amygdalus, P. cerasoides and P. armeniaca with an efficacy of P. domestica comparable to P. africana and can be used as the potential backup of Pygeum for the management of BPH.

Genome-wide association links candidate genes to resistance to Plum Pox Virus in apricot (Prunus armeniaca)

In fruit tree species, many important traits have been characterized genetically by using single-family descent mapping in progenies segregating for the traits. However, most mapped loci have not been sufficiently resolved to the individual genes due to insufficient progeny sizes for high resolution mapping and the previous lack of whole-genome sequence resources of the study species. To address this problem for Plum Pox Virus (PPV) candidate resistance gene identification in Prunus species, we implemented a genome-wide association (GWA) approach in apricot. This study exploited the broad genetic diversity of the apricot (Prunus armeniaca) germplasm containing resistance to PPV, next-generation sequence-based genotyping, and the high-quality peach (Prunus persica) genome reference sequence for single nucleotide polymorphism (SNP) identification. The results of this GWA study validated previously reported PPV resistance quantitative trait loci (QTL) intervals, highlighted other potential resistance loci, and resolved each to a limited set of candidate genes for further study. This work substantiates the association genetics approach for resolution of QTL to candidate genes in apricot and suggests that this approach could simplify identification of other candidate genes for other marked trait intervals in this germplasm.