Abstract

BackgroundRice (Oryza sativa L.) Chalkiness, the opaque part in the kernel endosperm formed by loosely piled starch and protein bodies. Chalkiness is a complex quantitative trait regulated by multiple genes and various environmental factors. Phytohormones play important roles in the regulation of chalkiness formation but the underlying molecular mechanism is still unclear at present.ResultsIn this research, Xiangzaoxian24 (X24, pure line of indica rice with high-chalkiness) and its origin parents Xiangzaoxian11 (X11, female parent, pure line of indica rice with high-chalkiness) and Xiangzaoxian7 (X7, male parent, pure line of indica rice with low-chalkiness) were used as materials. The phenotype, physiological and biochemical traits combined with transcriptome analysis were conducted to illustrate the dynamic process and transcriptional regulation of rice chalkiness formation. Impressively, phytohormonal contents and multiple phytohormonal signals were significantly different in chalky caryopsis, suggesting the involvement of phytohormones, particularly ABA and auxin, in the regulation of rice chalkiness formation, through the interaction of multiple transcription factors and their downstream regulators.ConclusionThese results indicated that chalkiness formation is a dynamic process associated with multiple genes, forming a complex regulatory network in which phytohormones play important roles. These results provided informative clues for illustrating the regulatory mechanisms of chalkiness formation in rice.

Highlights

  • Rice (Oryza sativa L.) Chalkiness, the opaque part in the kernel endosperm formed by loosely piled starch and protein bodies

  • The Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis of ­DEGHL showed that ­DEGHL mainly belong to metabolic pathways, biosynthesis of secondary metabolites at 8 days after heading (DAH), and ­DEGHL mainly belong to metabolic pathways, biosynthesis of secondary metabolites, phenylpropanoid biosynthesis, starch and sucrose metabolism at 12 DAH and 16 DAH (Supplementary Fig. 1F)

  • These ­DEGHL were closely related to caryopsis development, suggesting that chalkiness formation is a dynamic process regulated by multiple genes

Read more

Summary

Introduction

Rice (Oryza sativa L.) Chalkiness, the opaque part in the kernel endosperm formed by loosely piled starch and protein bodies. Chalkiness is a complex quantitative trait regulated by multiple genes and various environmental factors. Chalkiness, a negative trait for rice quality, represents the white/opaque part in rice (Oryza sativa L.) endosperm. Multiple QTLs contributing to grain chalkiness have been mapped across all 12 chromosomes of the rice genome [4]. Xie et al BMC Plant Biol (2021) 21:308 percentage of grains with chalkiness (PGWC), qPGWC-7 [5] and qPGWC-9 [6], are located on chromosomes 7 and 9 respectively. Being a QTL for the percentage of chalky grains (PCG), qPCG1 is located in a 139 kb region on the long arm of chromosome 1 [8]. Several chalkiness related QTLs and genes were isolated and functionally analyzed, the formation and regulation mechanism of rice chalkiness is far from clear [10, 11]

Methods
Results
Discussion
Conclusion
Full Text
Published version (Free)

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call