Open Access

ARTICLE

DWARF and SMALL SEED1, a Novel Allele of OsDWARF, Controls Rice Plant Architecture, Seed Size, and Chlorophyll Biosynthesis

Yan Li¹, Renquan Huang¹, Jianrong Li¹, Xiaozhen Huang¹, Xiaofang Zeng^1,*, Degang Zhao^1,2,*

1 Key Laboratory of Plant Resources Conservation and Germplasm Innovation in Mountainous Region, Ministry of Education, Institute of Agro-Bioengineering and College of Life Sciences, Guizhou University, Guiyang, 550025, China
2 Guiyang Station for DUS Testing Center of New Plant Varieties of China in Guizhou Academy of Agricultural Sciences, Guiyang, 550006, China

* Corresponding Authors: Xiaofang Zeng. Email: ; Degang Zhao. Email:

Phyton-International Journal of Experimental Botany 2021, 90(1), 111-127. https://doi.org/10.32604/phyton.2020.013933

Received 26 August 2020; Accepted 28 September 2020; Issue published 20 November 2020

Abstract

Plant architecture is a vital agronomic trait to control yield in rice (Oryza sativa L.). A dwarf and small seed 1 (dss1) mutant were obtained from the ethyl methanesulfonate (EMS) mutagenized progeny of a Guizhou glutinous landrace cultivar, Lipingzabianhe. The dss1 mutant displayed phenotypes similar to those of brassinosteroid (BR) deficient mutants, such as dwarfing, dark green and rugose erect leaves, small seeds, and loner neck internode panicles with primary branching. In our previous study, the underlying DSS1 gene was isolated, a novel allele of OsDWARF (OsBR6ox) that encodes a cytochrome P450 protein involved in the BR biosynthetic pathway by MutMap technology. In this work, we confirmed that a Thr335Ile amino acid substitution residing in DSS1/OsDWARF was responsible for the dwarf, panicle architecture, and small seed phenotypes in the dss1 mutants by genetic transformation experiments. The overexpression of OsDWARF in the dss1 mutant background could not only recover dss1 to the normal plant height and panicle architecture but also rescued normal leaf angles, seed size, and leaf color. Thus, the specific mutation in DSS1/OsDWARF influenced plant architecture, seed size, and chlorophyll biosynthesis.

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Keywords

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