Work

Balancing biomass and starch accumulation in duckweed: Unraveling the regulation mechanism of nutrient concentration via transcriptomics

Year: 2026

Type: article

Abstract: Duckweed has rapid growth, high starch content, and is easily regulated, making it a novel starch resource. Nutrient restriction accelerates starch accumulation in duckweed. However, the impact of changes in the nutrient concentration regulatory mechanism underlying starch accumulation remains unclear. This study optimized the nutrient concentration and analyzed key parameters of Spirodela polyrhiza ZH0196 starch accumulation, including starch content, photosynthetic pigments, and soluble sugars, to clarify the role of nutrient concentration. It also conducted an investigation and identification of key enzyme activities and key metabolic pathways involved in starch accumulation. Results showed that Spirodela polyrhiza ZH0196 growth and starch accumulation responded differently to initial nutrient levels. The 0 % nutrient group had the highest AGPase enzyme activity (12.42 ± 1.58 U/mg protein) among all groups (1.8–8.5 U/mg protein), but its final starch output was lower than that of the 40 % group. As Spirodela polyrhiza ZH0196 grew and nutrient concentration declined, photosynthetic pigments and biomass decreased, while starch-synthetic enzyme activity increased, leading to starch accumulation. These processes are closely associated with photosynthetic metabolism. Analysis of differentially expressed genes revealed a downregulation in biological processes related to ATP and NADPH generation, while genes involved in starch-sucrose metabolism and glycolysis were upregulated. Overall, these findings demonstrate that Spirodela polyrhiza ZH0196 exhibits notable advantages under lower (40 %) nutrient concentrations by reducing biomass production and enhancing starch accumulation. This study provides a theoretical basis for regulating starch biosynthesis in duckweed and offers a potential technical strategy for sustainable duckweed cultivation as bioenergy.

Source: Industrial Crops and Products

DOI: 10.1016/j.indcrop.2025.122547

Authors: Dongjing Han, Ziqi Chen, Peng Zhang, Li Cheng, Yan Hong, Zhengbiao Gu

Institutions: Jiangnan University, Chinese Academy of Sciences, Center for Excellence in Molecular Plant Sciences

Language: English

Topic: Algal biology and biofuel production

Subfield: Renewable Energy, Sustainability and the Environment

Field: Energy

Domain: Physical Sciences

SDG: Zero hunger

Open Access status: gold

Estimated APC paid: $3,720