Microsatellites for detecting inconsistencies in Capsicum cultivars registration in Brazilian database: more than meets the eye

ABSTRACT In Brazil, cultivars are registered by National Register of Cultivars (RNC), which besides enabling commercialization of cultivar propagative material, also guarantees the producers genetic purity and identity of propagules. However, it is possible that the information about registration and commercialization of some cultivars is inaccurate. This study aims to analyze the use of microsatellite markers to detect inconsistencies in data of Capsicum spp. cultivars obtained from the official database (CultivarWeb). Seven cultivars were evaluated, three of them were through genetic identity analysis (Amarela Comprida, De Cayenne and Cayenne Long Slin) and the others were used as standard for the species C. annuum, C. frutescens and C. chinense. Thirty-three microsatellite loci were polymorphic and presented 76 alleles (an average of 2.3 alleles/locus). Fixation Index (F) showed high homozygosis and estimators of genetic diversity (Ho and I) presented low genetic diversity among cultivars. The molecular analysis, represented in a dendrogram and in Principal Coordinate Analysis Chart (PCOA), showed that the investigated cultivars belong to C. annuum, contrary to what is registered in CultivarWeb, which indicates that such cultivars belong to the species C. frutescens. Thus, the authors recommend that the data in the CultivarWeb should be checked and enhanced.

摘要
在巴西，品种由国家品种登记册（National Register of Cultivars, RNC）进行登记。该登记系统不仅可实现品种繁殖材料的商业化流通，还能保障生产者繁殖体的遗传纯度与身份标识。然而，部分品种的登记与商业化信息可能存在不准确之处。本研究旨在利用微卫星标记，对从官方数据库CultivarWeb中获取的辣椒属（Capsicum spp.）品种数据的不一致性进行检测分析。本研究共评估7个品种，其中3个品种（Amarela Comprida、De Cayenne及Cayenne Long Slin）开展了遗传身份分析，其余4个品种分别作为一年生辣椒（C. annuum）、灌木辣椒（C. frutescens）和中华辣椒（C. chinense）的参照标准。本次实验共检测到33个多态性微卫星位点，总计扩增得到76个等位基因，平均每个位点2.3个等位基因。固定指数（Fixation Index, F）显示出较高的纯合性水平，而遗传多样性估计值（观测杂合度Ho与香农信息指数I）则表明供试品种间的遗传多样性水平较低。基于聚类树状图与主坐标分析图（Principal Coordinate Analysis Chart, PCOA）的分子分析结果显示，供试品种应归属于一年生辣椒（C. annuum），但CultivarWeb数据库中的登记信息却将此类品种归类为灌木辣椒（C. frutescens）。据此，研究人员建议对CultivarWeb数据库中的相关数据进行核查与完善。