Morphological changes during juvenile-to-adult phase transition in sorghum.
Morphological changes during juvenile-to-adult phase transition in sorghum.
复制标题
高粱幼年期向成年期转变过程中的形态变化。
DOI：
10.1007/s00425-019-03251-x
复制
发表时间：
2019
期刊：
影响因子：
4.3
通讯作者：
Tezuka T and Yokoi S
中科院分区：
文献类型：
--
作者：
Hashimoto S;Tezuka T and Yokoi S
主要结论形态标记和遗传标记表明，高粱幼体向成体的转变发生在第四叶和第五叶期。从幼体到成体(JA)的阶段转换是优化植物营养生长和生殖成功的一个重要事件。在作为人类重要食物来源的禾本科作物中，对JA相变的研究仅限于水稻和玉米。我们研究了高粱早期发育过程中的形态和遗传变化，发现在营养的早期阶段，地上部的构型发生了巨大的变化。观察到叶片大小、叶形、毛状体数量和茎顶端分生组织的大小发生了变化。特别是第五叶和上部叶片的长宽比与第二至第四叶的长宽比完全不同。第五叶和上部叶的近轴侧有毛，下部叶上没有毛。我们还分析了两个已知的JA相变分子标记的microRNAs的表达，发现miR156在第二到第四叶的表达最高，然后逐渐下调，而miR172的表达则遵循相反的模式。这些结果表明，高粱的第二叶和第三叶为幼龄期，第四和第五叶为过渡期，第六叶和上部叶为成熟期。因此，JA相变发生在第四和第五叶阶段。这些发现有望对了解高粱的早期发育有帮助。
Main conclusionMorphological and genetic markers indicate that in sorghum, the juvenile-to-adult phase transition occurs during the fourth and fifth leaf stages. This timing differs from those reported for other plants.AbstractThe juvenile-to-adult (JA) phase transition is an important event for optimizing vegetative growth and reproductive success in plants. Among the Poaceae crops, which are a vital food source for humans, studies of the JA phase transition have been restricted to rice and maize. We studied the morphological and genetic changes that occur during the early development of sorghum and found that dramatic changes occur in shoot architecture during the early vegetative stages. Changes were observed in leaf size, leaf shape, numbers of trichomes, and size of the shoot apical meristem. In particular, the length/width ratios of the leaf blades in the fifth and upper leaves were completely different from those of the second to fourth leaves. The fifth and upper leaves have trichomes on their adaxial sides, which were absent on the lower leaves. We also analyzed expression of two microRNAs that are known to be molecular markers of the JA phase transition and found that expression ofmiR156was highest in the second to fourth leaves and then was gradually down-regulated, whereasmiR172expression followed the opposite pattern. These results suggest that in sorghum, the second and third leaves represent the juvenile phase, the fourth and fifth leaves are in the transition stage, and the sixth and upper leaves are in the adult phase. Thus, the JA phase transition occurs during the fourth and fifth leaf stages. These findings are expected to be useful for understanding the early development of sorghum.