ABSTRACT

The aim of this study was to assess the extent of genetic diversity among and within tef populations collected from acid-affected soils in Ethiopia, and to test the cross-amplification of markers linked to Al-toxicity tolerance in other cereals. Forty-two tef genotypes were studied using 33 highly polymorphic SSRs. About 55% of the amplified putative alleles were effective in discriminating the genotypes. The mean PIC value was 0.66, suggesting that the majority of the markers had high discriminatory power. The population structure analysis revealed the presence of two genetically distinct populations and clearly distinguished landraces from the rest. A significant difference in genetic diversity parameters was observed between the two inferred populations. The landraces consistently had higher values for all of the diversity parameters and had contrastingly a higher value of private alleles. The AMOVA showed highly significant (P = 0.001) genetic variation among tef populations and among genotypes, with variance contribution of 17% and 67%, respectively. Eighty-two percent of the Al-toxicity tolerance markers amplified 84 alleles. This finding suggests the possibility of in-situ preservation of rare alleles that may confer acid tolerance through the improvement of available landraces in acid affected soils. Thus, urgent efforts are needed to collect accessions from areas with acid-affected soils.

摘要

本研究的目的是评估从埃塞俄比亚受酸影响的土壤中收集的 tef 种群之间和内部的遗传多样性程度，并测试与其他谷物中铝毒性耐受性相关的标记的交叉扩增。使用 33 个高度多态性的 SSR 研究了 42 个 tef 基因型。大约 55% 的扩增推定等位基因可有效区分基因型。平均 PIC 值为 0.66，表明大多数标记具有较高的辨别力。种群结构分析揭示了两个遗传上不同的种群的存在，并将地方品种与其他种群明显区分开来。在两个推断种群之间观察到遗传多样性参数的显着差异。地方品种的所有多样性参数始终具有较高的值，而私有等位基因的值则相反。AMOVA 显示非常显着（P = 0.001) tef 种群和基因型之间的遗传变异，方差贡献分别为 17% 和 67%。82% 的铝毒性耐受标记扩增了 84 个等位基因。这一发现表明，可以通过改善受酸性土壤中的可用地方品种，就地保存稀有等位基因，这些基因可能赋予耐酸性。因此，需要紧急努力从受酸影响的土壤地区收集材料。