Gonin Mathieu, Bergougnoux Véronique, Nguyen Thu D, Gantet Pascal, Champion Antony
Université de Montpellier, IRD, UMR DIADE, 34,394 Montpellier, France.
Department of Molecular Biology, Centre of the Region Haná for Biotechnological and Agricultural Research, Palacký University Olomouc, Šlechtitelů 27, 783 71 Olomouc, Czech Republic.
Plants (Basel). 2019 Jul 22;8(7):240. doi: 10.3390/plants8070240.
The spermatophyte root system is composed of a primary root that develops from an embryonically formed root meristem, and of different post-embryonic root types: lateral and adventitious roots. Adventitious roots, arising from the stem of the plants, are the main component of the mature root system of many plants. Their development can also be induced in response to adverse environmental conditions or stresses. Here, in this review, we report on the morphological and functional diversity of adventitious roots and their origin. The hormonal and molecular regulation of the constitutive and inducible adventitious root initiation and development is discussed. Recent data confirmed the crucial role of the auxin/cytokinin balance in adventitious rooting. Nevertheless, other hormones must be considered. At the genetic level, adventitious root formation integrates the transduction of external signals, as well as a core auxin-regulated developmental pathway that is shared with lateral root formation. The knowledge acquired from adventitious root development opens new perspectives to improve micropropagation by cutting in recalcitrant species, root system architecture of crops such as cereals, and to understand how plants adapted during evolution to the terrestrial environment by producing different post-embryonic root types.
侧根和不定根。不定根从植物的茎部长出，是许多植物成熟根系的主要组成部分。它们的发育也可因不利的环境条件或胁迫而被诱导。在此综述中，我们报道了不定根的形态和功能多样性及其起源。讨论了组成型和诱导型不定根起始与发育的激素和分子调控。最新数据证实了生长素/细胞分裂素平衡在不定根形成中的关键作用。然而，必须考虑其他激素。在基因水平上，不定根的形成整合了外部信号的转导，以及与侧根形成共享的核心生长素调节的发育途径。从不定根发育中获得的知识为改善难繁殖物种的扦插微繁殖、谷物等作物的根系结构，以及理解植物在进化过程中如何通过产生不同的胚后根类型适应陆地环境开辟了新的前景。
