Díaz B G, Argollo D M, Franco M C, Nucci S M, Siqueira W J, de Laat D M, Colombo C A
Centro de Pesquisa e Desenvolvimento de Recursos Genéticos Vegetais, , , Brasil
Centro de Pesquisa e Desenvolvimento de Recursos Genéticos Vegetais, , , Brasil.
Genet Mol Res. 2017 May 31;16(2):gmr-16-02-gmr.16029683. doi: 10.4238/gmr16029683.
Jatropha curcas L. is a highly promising oilseed for sustainable production of biofuels and bio-kerosene due to its high oil content and excellent quality. However, it is a perennial and incipiently domesticated species with none stable cultivar created until now despite genetic breeding programs in progress in several countries. Knowledge of the genetic structure and diversity of the species is a necessary step for breeding programs. The molecular marker can be used as a tool for speed up the process. This study was carried out to assess genetic diversity of a germplasm bank represented by J. curcas accessions from different provenance beside interspecific hybrid and backcrosses generated by IAC breeding programs using inter-simple sequence repeat markers. The molecular study revealed 271 bands of which 98.9% were polymorphic with an average of 22.7 polymorphic bands per primer. Genetic diversity of the germplasm evaluated was slightly higher than other germplasm around the world and ranged from 0.55 to 0.86 with an average of 0.59 (Jaccard index). Cluster analysis (UPGMA) revealed no clear grouping as to the geographical origin of accessions, consistent with genetic structure analysis using the Structure software. For diversity analysis between groups, accessions were divided into eight groups by origin. Nei's genetic distance between groups was 0.14. The results showed the importance of Mexican accessions, congeneric wild species, and interspecific hybrids for conservation and development of new genotypes in breeding programs.
麻疯树因其含油量高且品质优良，是可持续生产生物燃料和生物煤油的极具潜力的油料作物。然而，它是一种多年生且刚刚开始驯化的物种，尽管多个国家都在进行遗传育种计划，但至今尚未培育出稳定的品种。了解该物种的遗传结构和多样性是育种计划的必要步骤。分子标记可作为加速这一进程的工具。本研究旨在利用简单序列重复区间标记，评估由来自不同产地的麻疯树种质库以及国际热带农业中心（IAC）育种计划产生的种间杂交种和回交种所代表的种质的遗传多样性。分子研究共检测到271条带，其中98.9%为多态性带，每个引物平均有22.7条多态性带。所评估种质的遗传多样性略高于世界其他种质，范围在0.55至0.86之间，平均为0.59（杰卡德指数）。聚类分析（非加权组平均法）显示，种质的地理起源没有明显的分组，这与使用Structure软件进行的遗传结构分析结果一致。为了进行组间多样性分析，种质按原产地分为八组。组间的奈氏遗传距离为0.14。结果表明，墨西哥种质、同属野生种和种间杂交种对于育种计划中保护和开发新基因型具有重要意义。
