Rapid Crown Root Development Confers Tolerance to Zinc Deficiency in Rice.
Rapid Crown Root Development Confers Tolerance to Zinc Deficiency in Rice.
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DOI：
10.3389/fpls.2016.00428
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发表时间：
2016
影响因子：
5.6
通讯作者：
Wissuwa M
中科院分区：
文献类型：
--
作者：
Nanda AK;Wissuwa M
锌缺乏是水稻的主要营养障碍之一。许多研究已经确定了锌高效水稻基因型，但缺乏锌耐性的因果机制仍然知之甚少。在这里，我们报告了一个详细的研究锌缺乏对水稻基因型冠根发育的影响，不同的耐受性，这种压力。锌缺乏延缓了锌高效和低效基因型的冠根发育和生物量积累，后者的影响更强。锌高效基因型早在移栽后3天（DAT），以锌缺乏的领域，并随后由总生物量显着增加7 DAT。锌低效基因型开发的新冠根很少，并没有增加生物量在第一个7天移栽后。这与锌高效基因型转移更高比例的地上部锌到他们的根，相比，锌低效基因型。此外，这些基因型不能有效地利用有限的锌根的发展。组织学分析表明，没有异常的冠组织锌高效或低效的基因型，这将建议冠根出现受阻。因此，我们得出结论，冠根发生率的基因型之间的锌缺乏的差异影响。快速冠根发育，移栽后，被确定为耐锌缺乏的主要原因性状和更好的锌从地上部到根的再转运是锌高效基因型的一个关键属性。
Zinc (Zn) deficiency is one of the leading nutrient disorders in rice (Oryza sativa). Many studies have identified Zn-efficient rice genotypes, but causal mechanisms for Zn deficiency tolerance remain poorly understood. Here, we report a detailed study of the impact of Zn deficiency on crown root development of rice genotypes, differing in their tolerance to this stress. Zn deficiency delayed crown root development and plant biomass accumulation in both Zn-efficient and inefficient genotypes, with the effects being much stronger in the latter. Zn-efficient genotypes had developed new crown roots as early as 3 days after transplanting (DAT) to a Zn deficient field and that was followed by a significant increase in total biomass by 7 DAT. Zn-inefficient genotypes developed few new crown roots and did not increase biomass during the first 7 days following transplanting. This correlated with Zn-efficient genotypes retranslocating a higher proportion of shoot-Zn to their roots, compared to Zn-inefficient genotypes. These latter genotypes were furthermore not efficient in utilizing the limited Zn for root development. Histological analyses indicated no anomalies in crown tissue of Zn-efficient or inefficient genotypes that would have suggested crown root emergence was impeded. We therefore conclude that the rate of crown root initiation was differentially affected by Zn deficiency between genotypes. Rapid crown root development, following transplanting, was identified as a main causative trait for tolerance to Zn deficiency and better Zn retranslocation from shoot to root was a key attribute of Zn-efficient genotypes.