Genetic Diversity and Differentiation of Alpinia Oxyphylla Miquel as Revealed by AFLP Markers

In this study, we analyzed the genetic diversity and population structure of 90 A. oxyphylla accessions from Hainan island using amplified fragment length polymorphism (AFLP) markers. These 90 accessions were composed of 15 populations from different geographic locations and divided into 4 clusters (A, B, C, and D) using the Unweighted pair group method based on arithmetic average (UPGMA). The genetic similarity between individuals ranged from 0.47 to 1.00 (average of 0.74), and most accessions from the same geographic population were grouped together. Principal coordinate analysis (PCA) showed a clear distinction among three clusters (A, B and C). Based on the loci information, the population structure analysis results by STRUCTURE and TESS were consistent with the clustering of PCA. Nine AFLP primer combinations generated 1537 polymorphic bands displaying rich polymorphism, thus indicating high genetic diversity among these 15 populations with an average Nei’s gene diversity of 0.1328 ± 0.160. In conclusion, AFLP markers efficiently analyzed the genetic diversity in A. oxyphylla, demonstrating highly significant genetic variation within and among populations. However, intrapopulation genetic variance was much higher than interpopulation variability, suggesting that efforts should be made for in situ germplasm conservation and resistant varieties cultivation.

Morphological Characterization of Southern Jalisco, Mexico, Pomegranate Genotypes Using AFLP Markers

Pomegranate is gaining popularity because of its proved nutraceutical properties and is highly adaptable to different climates. In southern Jalisco, Mexico, 18 genotypes were characterized on the basis of fruit characteristics (21 traits) and AFLP (Amplified Fragment length polymorphism) markers. The first three components of a principal components analysis (PCA) explained 71.5% of the variation. The most important variables were related to fruit size and weight. Fruit weight, equatorial diameter, polar diameter, and rind and membrane weight were the variables that most contributed to principal component one (PC1) 46.4%. The variables juice per fruit, edible proportion, proportion of rind and membrane, and seed length contributed most to principal component two (PC2) 15.2%, while juice pH, weight of one seed, and aril width contributed the most to principal component three (PC3) 9.9%. With the six combinations of AFLP primers, 315 fragments were obtained (an average of 52.5 fragments per primer); of these, 229 were polymorphic (72.7% polymorphism). Grouping by both morphological traits and AFLP markers separated all the evaluated individuals so that there were no repeated genotypes. In both analyses, the grouping did not obey geographic origin of the genotypes (r = −0.35), suggesting that both techniques were useful and complementary in the characterization of pomegranate genotypes. The commercial cultivars Wonderful and Apaseo had low levels of similarity to genotypes from southern Jalisco. The level of polymorphism found and compared with the results obtained by other authors suggests that the pomegranate genotypes evaluated are highly polymorphic. We found broad genetic diversity that can be used in breeding programs.

Autochthonous Austrian Varieties of Prunus avium L. Represent a Regional Gene Pool, Assessed Using SSR and AFLP Markers

Sweet cherry production faces new challenges that necessitate the exploitation of genetic resources such as varietal collections and landraces in breeding programs. A harmonized approach to characterization is key for an optimal utilization of germplasm in breeding. This study reports the genotyping of 63 sweet cherry accessions using a harmonized set of 11 simple sequence repeat (SSR) markers optimized in two multiplexed PCR reactions. Thirty-eight distinct allelic profiles were identified. The set of SSR markers chosen proved highly informative in these germplasm; an average of 6.3 alleles per locus, a PIC value of 0.59 and above-average expected and observed heterozygosity levels were detected. Additionally, 223 amplified fragment length polymorphism (AFLP) markers derived from eight selective primer combinations were employed to further differentiate 17 closely related accessions, confirming the SSR analysis. Genetic relationships between internationally known old cultivars were revealed: SSR fingerprints of “Schneiders Späte Knorpelkirsche” and “Germersdorfer” were found to be identical to those of the standard cultivar “Noire de Meched”, among others, whereas four accessions known as “Hedelfinger Riesenkirsche” and four known as “Große Schwarze Knorpelkirsche” showed allelic differences at various loci. The genetic diversity of locally-grown cultivars worldwide might be currently underestimated. Several autochthonous Austrian sweet cherry germplasm accessions were genotyped for the first time and their genetic relationships analyzed and discussed. Interestingly, seven Austrian sweet cherry landraces were shown to be clearly genetically separated from international and modern varieties, indicating that Austrian germplasm could include valuable genetic resources for future breeding efforts.