Diploid japanese plum (Prunus salicina Lindl.) cultivars are commonly self-incompatible. To date, 14 incompatibility alleles (S-alleles) have been identified and labeled with alphabetical (Sa-Sn) and 5 with numeric codes (S1, S3-S6). We applied polymerase chain reaction amplification of the S-RNase alleles with degenerate and allele-specific primers in 10 japanese plum cultivars and two pluots of unknown incompatibility alleles. Besides DNA sequencing, an additional method for the exact length determination of the first intron region was used for the first time for S-genotype japanese plums. The S3-allele was shown to correspond to Sk in the alphabetic nomenclature, S4 to Sc, S5 to Se, and S6 to Sf. The S5-allele-specific primer can be used as a reliable marker for self-compatibility in japanese plum. ‘Black Amber’, ‘October Sun’, ‘TC Sun’, and ‘Super Giant’ share the SbSc genotype, which was confirmed by test crosses. These cultivars belong to the widest incompatibility group currently known in japanese plum. An additional incompatibility group (ScSh) was established, including ‘Green Sun’ and ‘Queen Rosa’, a cultivar formerly known as a universal donor. By incorporating all previous and recent results, a table was assembled including 49 cultivars assigned to I–VII incompatibility groups, to the self-compatible group and to the group O of unique genotypes. These data may considerably contribute to further growing and breeding activities.
Fruits of 11 cherry laurel (Laurocerasus officinalis L.) genotypes grown in a single location, Rize province, were analyzed for their fruit characteristics. Both physical and chemical characteristics of cherry laurel fruits were significantly influenced by genotypes. Fruit weight, the number of fruits per cluster, and flesh per seed ratio ranged between 1.87 and 4.01 g; 9.21 and 21.05, and 5.54 and 9.33, respectively. The genotypes R06 and R09 had the highest total anthocyanin [205 and 202 mg/100 g fresh weight (FW), respectively] and R06 and R11 had the highest total phenolic contents (503 and 481 mg/100 g FW, respectively). Total carotenoid and vitamin C contents ranged from 207 to 278 mg/100 g FW and 2.1 to 4.1 mg/100 g FW, respectively. Soluble solid content (SSC), crude fiber, crude protein, pectin, ash, and pH of genotypes fell between 9.64% and 17.10%; 0.44% and 0.85%; 1.44% and 2.09%; 0.20% and 0.47%; 0.25% and 0.71%, and 4.30 and 4.93, respectively. Data demonstrated that the great variations observed in the physical and chemical characteristics of individual cherry laurel genotypes might be explained by genotypic effect because all genotypes grew under the same ecological conditions. The investigated genotypes seemed to be perspective in health promotion.
The S-genotypes of a set of Turkish and Hungarian apricot (Prunus armeniaca L.) cultivars were determined by polymerase chain reaction (PCR) amplification of their S-RNase intron regions. In addition, the S-genotyping method was extended to the SFB gene to detect the non-functional SC-haplotype and hence reliably identify self-compatible apricot cultivars. We determined the complete S-genotype of 51 cultivars and the partial S-genotype of four cultivars. A total of 32 different S-genotypes were assigned to the 51 cultivars, and many of them (28) were classified into newly established cross-incompatibility groups III through XIV. Another 12 cultivars demonstrated unique incompatible genotypes and seven self-compatible cultivars were identified in the examined accessions. The fact that Turkish and Hungarian apricot cultivars carry 12 and five S-alleles, respectively, and all five alleles detected in Hungarian cultivars were also present in Turkish apricots furnished molecular evidence supporting the long-suspected historical connection between Hungarian and Turkish apricots. The connection between these two gene pools appeared to be relatively recent and associated with historical events dating back 300 years. Our results confirm that Turkish germplasm contributed considerably to the development of several desirable Hungarian apricot cultivars. Results suggest that the mutation rendering the SC-haplotype non-functional might have occurred somewhere east of central Turkey.
The most commercially grown peach [Prunus persica (L.) Batsch.] cultivars do not require cross-pollination for reasonable fruit set; however, self-incompatibility is a well-known feature within the Prunoideae subfamily. Isoelectric focusing and native polyacrylamide gel electrophoresis of S-ribonucleases; PCR analyses of S-RNase and S-haplotype-specific F-box genes as well as DNA sequencing were carried out to survey the self-(in)compatibility allele pool and to uncover the nature of self-compatibility in peach. From 25 cultivars and hybrids with considerable diversity in phenotype and origin, only two S-haplotypes were detected. Allele identity could be checked by exact length determination of the PCR-amplified fragments and/or partial sequencing of the peach S1-, S2-, and Prunus davidiana (Carr.) Franch. S1-RNases. S-RNases of peach were detected to possess ribonuclease activity, and a single nucleotide polymorphism in the S1-RNase was shown, which represents a synonymous substitution and does not change the amino acid present at the position in the protein. A 700-bp fragment of the peach SFB gene was PCR-amplified, which is similar to the fragment size of functional Prunus L. SFBs. All data obtained in this study may support the contribution of genes outside the S-locus to the self-compatible phenotype of peaches.
A traditional cultivar, Besztercei Bt.2, and a clone of an autochthonous landrace (Nemtudom P3) of the hexaploid European plum (Prunus domestica) were studied to highlight their breeding perspectives. Five self-incompatibility ribonuclease (S-RNase) alleles were detected in both cultivars, with one allele shared. DNA sequence analysis confirmed it as a new, previously unidentified allele in P. domestica, which we labeled as S18. This allele was found to share ∼99% identity with the Prunus spinosa SB-RNase allele. Because Prunus species are readily hybridizing, sequence variations in 10 chloroplast DNA regions and nuclear internal transcribed spacers were studied to check if ‘Nemtudom P3’ and ‘Besztercei Bt.2’ are indeed P. domestica. The majority-rule consensus tree of maximum likelihood and Bayesian inferences confirmed it, and also indicated genetic differentiation with ‘Nemtudom P3’ and ‘Besztercei Bt.2’ forming a statistically supported subclade within the P. domestica germplasm. Our results pointed to some regions of the P. domestica chloroplast genome (trnS-trnG-trnG, trnC-ycf6, and trnD-trnT) that can be used to detect intraspecific variations. The proportion of parsimony informative characters compared with the total length of amplified regions was the highest in the case of nrITS with 12.1%. The S-genotyping of 68 wild-growing Nemtudom trees showed the genetic consequences of long-term vegetative propagation and occasional crossing between Besztercei and Nemtudom accessions. Controlled pollinations confirmed the self-compatibility of ‘Nemtudom P3’. By clarifying their phylogenetic position, and characterizing the S-locus, our results will help breeding P. domestica cultivars and pave the way to understanding how the S-locus works in a hexaploid Prunus species.
Fruits of four berry species (strawberry, raspberry, red and black currants) were compared in their elemental composition (Al, B, Ba, Ca, Cu, Fe, K, Mg, Mn, Na, P, and Zn) and redox parameters involving total phenol content (TPC), ferric reducing ability (FRAP), 2,2′-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging, and total radical scavenger activity (TRSA). Berry cultivars contained significantly higher (P ≤ 0.05) amounts of most detected elements as compared with apple with many maximum elemental values demonstrated by the black currant ‘Otelo’. Black currant also had the greatest antioxidant capacity as demonstrated through all conducted assays. The results obtained through FRAP, TPC, and TRSA assays were closely correlated, whereas TRSA and DPPH varied independently. Our study provides valuable information on the antioxidant capacity of several berry species grown in Hungary and highlights the crucial influence of cultivar on elemental content and antioxidant power of berry fruits. This study demonstrated the ability to select berry cultivars for specific nutritional purposes or assign parental lines in functional breeding programs.
The hexaploid European plum (Prunus domestica L.) is an economically important fruit species with limited information on its genetic structure. Our objective was to fingerprint 55 cultivars using seven simple sequence repeat (SSR) markers to estimate the polymorphism level and determine allelic variation and genetic relationships among local and international cultivars. The primer pairs amplified a total of 135 alleles ranging from six to 27 alleles per locus, displaying high polymorphism. All genotypes were clearly distinguished with the seven SSRs used in this study. In a neighbor-joining cluster analysis, cultivars belonging to the same species did not group together. Foreign modern cultivars clustered together, and Hungarian landraces positioned distantly from those. STRUCTURE analysis indicated three genetically distinct groups of the studied genotypes. Each cluster of Hungarian landrace cultivars received strong bootstrap support (89% to 100%). Most genotypes kept under identical name showed different DNA fingerprints. A principal component analysis (PCA) confirmed the information provided by the dendrogram and clarified the origin of ʻFehérszilva’. Our results confirmed the potential of the application of SSR markers in plum breeding.