背景:木薯是三大马铃薯作物之一,也是全球第六大粮食作物。提高产量仍然是木薯育种的主要目标。值得注意的是,株高显著影响作物的产量和品质;然而,木薯植物高度发育的潜在机制尚未阐明。
结果:在这项研究中,我们使用表型研究了木薯植物高度发育的机制,解剖学,和转录组学分析。表型和解剖学分析表明,与高茎木薯品种相比,矮茎木薯品种的植物高度显着降低,节间组织木质部面积显着增加。同时,生理分析表明,矮木薯的木质素含量明显高于高木薯。值得注意的是,节间组织的转录组分析确定了几个差异表达基因参与细胞壁合成和扩增,植物激素信号转导,苯丙素生物合成,和两个木薯品种之间的类黄酮生物合成。
结论:我们的研究结果表明,节间组织细胞分裂,次生壁木质化,激素相关基因的表达在木薯株高发育中起重要作用。最终,这项研究为木薯株高形态发生机制提供了新的见解,并确定了与株高相关的候选调控基因,这些基因可以作为未来作物矮化育种的宝贵遗传资源。
BACKGROUND: Cassava is one of three major potato crops and the sixth most important food crop globally. Improving yield remains a primary aim in cassava breeding. Notably, plant height significantly impacts the yield and quality of crops; however, the mechanisms underlying cassava plant height development are yet to be elucidated.
RESULTS: In this study, we investigated the mechanisms responsible for cassava plant height development using phenotypic, anatomical, and transcriptomic analyses. Phenotypic and anatomical analysis revealed that compared to the high-stem cassava cultivar, the dwarf-stem cassava cultivar exhibited a significant reduction in plant height and a notable increase in internode tissue xylem area. Meanwhile, physiological analysis demonstrated that the lignin content of dwarf cassava was significantly higher than that of high cassava. Notably, transcriptome analysis of internode tissues identified several differentially expressed genes involved in cell wall synthesis and expansion, plant hormone signal transduction, phenylpropanoid biosynthesis, and flavonoid biosynthesis between the two cassava cultivars.
CONCLUSIONS: Our findings suggest that internode tissue cell division, secondary wall lignification, and hormone-related gene expression play important roles in cassava plant height development. Ultimately, this study provides new insights into the mechanisms of plant height morphogenesis in cassava and identifies candidate regulatory genes associated with plant height that can serve as valuable genetic resources for future crop dwarfing breeding.