OsSPL14, identified as IDEAL PLANT ARCHITECTURE1 (IPA1) or WEALTHY FARMER’S PANICLE (WFP) gene, plays a critical role in regulating rice plant architecture. Here, the study showed that OsSPL14-overexpression transgenic rice plants had shorter growth period, short-narrow flag leaves, and thick-green leaves. Compared with wild type plant ‘MH86’, transgenic plants had higher chlorophyll a (Ca), chlorophyll b (Cb) and carotenoid (Cx) content at both seedling and maturity stage. Meanwhile, transcriptome analysis identified 473 up-regulated and 103 down-regulated genes in transgenic plant. The expression of differentially expressed genes (DEGs) involved in carotenoid biosynthesis, abscisic acid (ABA) metabolism and lignin biosynthesis increased significantly. Most of DEGs participated in “plant hormone signal transduction” and “starch and sucrose metabolism” are also up-regulated in transgenic plant. In addition, there were higher levels of ABA and gibberellin acid (GA3) in OsSPL14-overexpression transgenic plants. Moreover, the content of culm lignin, cellulose, silicon and potassium all increased dramatically. Thus, these results demonstrate that overexpression of OsSPL14 has influence on leaf development, hormone level and culm composition in rice, which provide more insight into understanding the function of OsSPL14. Highlight OsSPL14-overexpression transgenic plants showed shorter growth period, short-narrow flag leaves, and thick-green leaves. Transcript profile, abscisic acid (ABA) and gibberellin acid (GA3) level, and culm composition also changed obviously.
