Biology Department, University of Leicester, University Road, Leicester LE1 7RH, UK.
J Exp Bot. 2012 Oct;63(17):6253-66. doi: 10.1093/jxb/ers281. Epub 2012 Oct 17.
Members of the core pooids represent the most important crops in temperate zones including wheat, barley, and oats. Their importance as crops is largely due to the grain, particularly the storage capabilities of the endosperm. In this study, a comprehensive survey of grain morphology and endosperm organization in representatives of wild and cultivated species throughout the core pooids was performed. As sister to the core pooid tribes Poeae, Aveneae, Triticeae, and Bromeae within the Pooideae subfamily, Brachypodium provides a taxonomically relevant reference point. Using macroscopic, histological, and molecular analyses distinct patterns of grain tissue organization in these species, focusing on the peripheral and modified aleurone, are described. The results indicate that aleurone organization is correlated with conventional grain quality characters such as grain shape and starch content. In addition to morphological and organizational variation, expression patterns of candidate gene markers underpinning this variation were examined. Features commonly associated with grains are largely defined by analyses on lineages within the Triticeae and knowledge of grain structure may be skewed as a result of the focus on wheat and barley. Specifically, the data suggest that the modified aleurone is largely restricted to species in the Triticeae tribe.
核心 Pooid 成员代表了温带地区最重要的作物，包括小麦、大麦和燕麦。它们作为作物的重要性主要在于其谷物，特别是胚乳的储存能力。在这项研究中，对核心 Pooid 中野生和栽培种代表的谷物形态和胚乳组织进行了全面调查。作为 Pooideae 亚科核心 Pooid 族 Poeae、Aveneae、Triticeae 和 Bromeae 的姐妹群，Brachypodium 提供了一个分类学上相关的参考点。使用宏观、组织学和分子分析，描述了这些物种中谷物组织的不同模式，重点是外围和改良糊粉层。结果表明，糊粉层组织与常规谷物品质特征（如谷物形状和淀粉含量）相关。除了形态和组织上的变化外，还研究了支持这种变化的候选基因标记的表达模式。与谷物相关的特征主要是通过对 Triticeae 谱系的分析来定义的，而对小麦和大麦的关注可能会导致对谷物结构的认识产生偏差。具体而言，数据表明改良糊粉层主要局限于 Triticeae 族的物种。
