The root is the organ responsible for the uptake of water and therefore has a very important role in drought tolerance. The aims of the present work were to characterize nine traits of the root system architecture (RSA) and the shoot dry weight (W) of twelve genotypes of Brachypodium spp. under water stress and to establish the relationship between RSA phenotyping traits and SSRs. Two culture media, one standard (SM) and one (PEG) to induced water stress have been used. In SM medium, B. stacei had the highest values of W and all the RSA traits, except the mean diameter of the seminal roots, followed by B. hybridum and B. distachyon. In the PEG medium, root length increased in B. distachyon, decreased in B. hybridum and remained the same in B. stacei. A two-way hierarchical cluster analysis from 117 polymorphic SSRs and the traits of the RSA of the Brachypodium spp. genotypes, was performed. Brachypodium genotypes were separated into three groups corresponding to each species. In the second way of the hierarchical clustering association were observed between five RSA variables and SSR markers, which could be useful in the search for genes or QTLs related to RSA characters.

中文翻译：

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腕足植物干旱胁迫响应特征的分子遗传分析。

根是负责水分吸收的器官，因此在耐旱性中具有非常重要的作用。本工作的目的是表征根系构架（RSA）的9个特征和短枝孢子12种基因型的茎干重量（W）。水分胁迫下建立RSA表型性状与SSRs的关系。已经使用两种培养基，一种用于诱导水分胁迫的标准品（SM）和一种用于诱导水分胁迫的（PEG）。在SM培养基中，除了精原的平均直径外，史泰坦芽孢杆菌均具有最高的W和所有RSA性状，其次是杂交芽孢杆菌和B. distachyon。在PEG培养基中，B。distachyon的根长增加，B。distachyon的根长减少。B. hybridum和B. stacei保持不变。从117个多态性SSR和短螺旋藻属RSA的特征进行双向分层聚类分析。进行基因分型。腕足动物的基因型被分为对应于每个物种的三组。在第二种方式中，在五个RSA变量和SSR标记之间观察到了层次聚类关联，这对于搜索与RSA字符相关的基因或QTL可能有用。