RGB1 Regulates Rice Panicle Architecture and Grain Filling Through Monitoring Cytokinin Level in Inflorescence Meristem and Grain Abscisic Acid Level During Filling Stage

doi:10.1016/j.rsci.2021.05.002

Abstract

Dongping Zhang, Minyan Zhang, Yuzhu Wang, Jiansheng Liang. RGB1 Regulates Rice Panicle Architecture and Grain Filling Through Monitoring Cytokinin Level in Inflorescence Meristem and Grain Abscisic Acid Level During Filling Stage[J]. Rice Science, 2021, 28(4): 317-321.

Figures/Tables 5

Fig. 1. Comparisons of panicle phenotype, grain filling characteristics and effects of abscisic acid (ABA) application between Wuyujing 8 (WYJ8) and RGB1Ri transgenic lines.A, Panicle phenotype. Scale bar, 1.5 cm. B, Panicle length (n = 10). C, Number of grains per panicle (n = 10). D, Increase in grain dry weight after flowering (n = 10). E and F, Grain starch content and starch accumulation rate at the different days after flowering and the effects of ABA application. Values are Mean ± SD (n = 3). * and ** indicate significant differences at the 0.05 and 0.01 levels, respectively.

Fig. S1. Comparison of grain size and 1000-grain weight between different genotypes. Data are Mean ± SD (n = 3). * indicate significant differences at the 0.05 level.

Fig. 2. Contents of cytokinins and abscisic acid (ABA) and expression levels of their related genes. A, Contents of zeatin-riboside (ZR) and zeatin (Z) in the inflorescence meristem quantitatively analyzed by high-performance liquid chromatography- tandem mass spectrometry (HPLC-MS/MS). B and C, Expression of cytokinin oxidase/dehydrogenase (CKXs) genes in the inflorescence meristem. D, Grain ABA content during grain filling stage quantitatively analyzed by HPLC-MS/MS. E and F, Changes in the expression profiles of ABA synthesis gene OsNCED5 and catabolism gene OsABA8ox2 in the grains during grain filling stage. Values are Mean ± SD (n = 3). ** indicate significant differences at the 0.01 level.

Fig. S2. Expression level of OsCKX1 and OsCKX3 in Wuyujing 8 and RGB1Ri transgenic lines. Data are Mean ± SD (n = 3). ** indicate significant differences at the 0.01 level.

Fig. S3. Effects of abscisic acid (ABA) application on expression of genes catalyzing sucrose catabolism and starch biosynthesis. Data are Mean ± SD (n = 3). ** indicate significant differences at the 0.01 level.

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