Semidwarf stature is a valuable agronomic trait in grain crops that reduces lodging and increases harvest index. A fundamental advance during the 1960s Green Revolution was the introduction of semidwarf cultivars of rice and wheat. Essentially, all semidwarf varieties of rice under cultivation today owe their diminished stature to a specific null mutation in the gibberellic acid (GA) biosynthesis gene, SD1 However, it is now well-established that, in addition to GAs, brassinosteroids and strigolactones also control plant height. In this review, we describe the synthesis and signaling pathways of these three hormones as understood in rice and discuss the mutants and transgenics in these pathways that confer semidwarfism and other valuable architectural traits. We propose that such genes offer underexploited opportunities for broadening the genetic basis and germplasm in semidwarf rice breeding.

中文翻译：

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矮化性状在历史和现代农业中的作用，以水稻为重点。

半矮化身材是粮食作物的一个有价值的农艺性状，可以减少倒伏并提高收获指数。20 世纪 60 年代绿色革命的一项根本性进展是引进了半矮化水稻和小麦品种。本质上，当今种植的所有半矮化水稻品种的矮化都归因于赤霉酸 (GA) 生物合成基因 SD1 的特定无效突变。然而，现在已经确定，除了 GA 之外，油菜素类固醇和独脚金内酯也可以控制株高。在这篇综述中，我们描述了水稻中这三种激素的合成和信号传导途径，并讨论了这些途径中赋予半侏儒症和其他有价值的结构特征的突变体和转基因。我们认为这些基因为拓宽半矮化水稻育种的遗传基础和种质提供了未充分利用的机会。