The current study focused on characterization of the underlying genetic divergence in inbred lines developed from local landraces of North Eastern Hill Region of India – a designated Asiatic maize diversity centre – following six generations of inbreeding. Substantial genetic differentiation was indicated based on very high to moderateFstvalues for 22 of the 38 simple sequence repeat markers studied. STRUCTURE analysis partitioned the subset into two distinct and one admixture subgroup (Populations I, II and III respectively) accompanied by a significant reduction in heterozygosity. Population II was further subdivided into subpopulations Pop-M9 and Pop-T9. Nei's pairwise genetic distance and populationFstvalues indicated that Populations I and II were more divergent with neighbour joining clustering analysis clearly defining landraces originating from the states of Tripura (Population II) and Sikkim (Population I) as most divergent. Principal coordinates analysis could explain 31.26% of the variation present in the subgroups wherein Population I was more variable. Analysis of molecular variance andFstcoefficients (P< 0.001) indicated 17% population structuring with 55% variation detected for individuals within populations. These results combined with the presence of phenotypic variability in the subgroups for yield traits supported by results of a preliminary partial diallel analysis strongly suggest the existence of distinct heterotic groups. Divergence studies are crucial for exploiting heterosis, and the current study would go a long way to help establish a germplasm base for developing varieties with improved agronomic performance and surer commercial prospects no reports of which are available thus far.

中文翻译：

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从印度东北山区 (NEHR) 本土品种培育的玉米 (Zea maysL.) 品系的遗传特征和差异研究

目前的研究侧重于描述印度东北山区当地地方品种（一个指定的亚洲玉米多样性中心）在经过六代近交后发展而来的自交系的潜在遗传差异。基于非常高到中等的显着遗传分化F英石研究的 38 个简单序列重复标记中的 22 个的值。结构分析将子集划分为两个不同的和一个混合子组（分别为种群 I、II 和 III），杂合性显着降低。种群 II 进一步细分为 Pop-M9 和 Pop-T9 亚群。Nei 的成对遗传距离和种群F英石值表明，种群 I 和 II 的差异更大，邻居加入聚类分析清楚地将源自特里普拉州（人口 II）和锡金州（人口 I）的地方品种定义为差异最大。主坐标分析可以解释 31.26% 的变异存在于群体 I 更易变的亚组中。分子变异分析和F英石系数 (磷< 0.001) 表明 17% 的人口结构具有 55% 的变异检测到人口中的个体。这些结果与由初步部分二等列分析结果支持的产量性状亚组中存在的表型变异性相结合，强烈表明存在不同的杂种优势组。差异研究对于利用杂种优势至关重要，目前的研究将大大有助于建立种质基础，以开发具有改善的农艺性能和更可靠的商业前景的品种，迄今为止尚无相关报道。