Identification of superior clones by RAPD technology in Xanthoceras sorbifolia Bge

Population Genetics and Development of a Core Collection from Elite Germplasms of Xanthoceras sorbifolium Based on Genome-Wide SNPs

Xanthoceras sorbifolium is one of the most important species of woody oil. In this study, whole genome re-sequencing of 119 X. sorbifolium germplasms was conducted and, after filtering, 105,685,557 high-quality SNPs were identified, which were used to perform population genetics and core collection development analyses. The results from the phylogenetic, population structure, and principal component analyses showed a high level of agreement, with 119 germplasms being classified into three main groups. The germplasms were not completely classified based on their geographical origins and flower colors; furthermore, the genetic backgrounds of these germplasms were complex and diverse. The average polymorphsim information content (PIC) values for the three inferred groups clustered by structure analysis and the six classified color groups were 0.2445 and 0.2628, respectively, indicating a low to medium informative degree of genetic diversity. Moreover, a core collection containing 29.4% (35) out of the 119 X. sorbifolium germplasms was established. Our results revealed the genetic diversity and structure of X. sorbifolium germplasms, and the development of a core collection will be useful for the efficient improvement of breeding programs and genome-wide association studies.

Genetic diversity of Xanthoceras sorbifolium bunge germplasm using morphological traits and microsatellite molecular markers

Xanthoceras sorbifolium Bunge has great potential for producing biodiesel. In order to select and evaluate appropriate germplasm to produce biodiesel, we analyzed the genetic diversity of Xanthoceras sorbifolium Bunge germplasm based on morphological traits and simple sequence repeats (SSRs) in this study. Fifty-six germplasm samples were evaluated using nine morphological traits and 23 SSR loci. Significant differences among germplasms were observed in eight morphological characters. The SSR markers analysis showed high genetic diversity among the germplasms. All SSRs had polymorphisms, and we detected 77 alleles in total. The number of alleles at each locus ranged from two to six, averaging 3.35 per marker. The polymorphic information content values ranged from 0.36 to 0.61, averaging 0.49. Expected heterozygosity, observed heterozygosity, and Shannon's information index calculations detected large genetic variations among germplasms. The high average number of alleles per locus and the allelic diversity observed in the set of genotypes analyzed indicated that the genetic base of this species is relatively wide. Thus, microsatellite markers can be used to efficiently distinguish Xanthoceras sorbifolium Bunge germplasms and assess their genetic diversity. Hundred-grain weight and lateral diameter were positively correlated with monounsaturated fatty acids and depended on genotype. These results suggest that seeds with higher hundred-grain weight and lateral diameter could be more suitable to produce biodiesel. Our data will lay a foundation for selecting appropriate germplasm to produce biodiesel based on seed phenotype and will contribute to the conservation and management of this important plant genetic resource.

Biotechnologies for the management of genetic resources for food and agriculture

In recent years, the land area under agriculture has declined as also has the rate of growth in agricultural productivity while the demand for food continues to escalate. The world population now stands at 7 billion and is expected to reach 9 billion in 2045. A broad range of agricultural genetic diversity needs to be available and utilized in order to feed this growing population. Climate change is an added threat to biodiversity that will significantly impact genetic resources for food and agriculture (GRFA) and food production. There is no simple, all-encompassing solution to the challenges of increasing productivity while conserving genetic diversity. Sustainable management of GRFA requires a multipronged approach, and as outlined in the paper, biotechnologies can provide powerful tools for the management of GRFA. These tools vary in complexity from those that are relatively simple to those that are more sophisticated. Further, advances in biotechnologies are occurring at a rapid pace and provide novel opportunities for more effective and efficient management of GRFA. Biotechnology applications must be integrated with ongoing conventional breeding and development programs in order to succeed. Additionally, the generation, adaptation, and adoption of biotechnologies require a consistent level of financial and human resources and appropriate policies need to be in place. These issues were also recognized by Member States at the FAO international technical conference on Agricultural Biotechnologies for Developing Countries (ABDC-10), which took place in March 2010 in Mexico. At the end of the conference, the Member States reached a number of key conclusions, agreeing, inter alia, that developing countries should significantly increase sustained investments in capacity building and the development and use of biotechnologies to maintain the natural resource base; that effective and enabling national biotechnology policies and science-based regulatory frameworks can facilitate the development and appropriate use of biotechnologies in developing countries; and that FAO and other relevant international organizations and donors should significantly increase their efforts to support the strengthening of national capacities in the development and appropriate use of pro-poor agricultural biotechnologies.