Open Access

ARTICLE

Effects of Manganese Toxicity on the Growth and Gene Expression at the Seedling Stage of Soybean

Ying Liu^1,3,*, Jingye Chen^1,3, Xiaohao Li^1,3, Shaoxia Yang¹, Hanqiao Hu^1,3, Yingbin Xue^2,3,*
1 Department of Biotechnology, College of Coastal Agricultural Sciences, Guangdong Ocean University, Zhanjiang, 524088, China
2 Department of Resources and Environmental Sciences, College of Chemistry and Environment, Guangdong Ocean University, Zhanjiang, 524088, China
3 South China Branch of National Saline-Alkali Tolerant Rice Technology Innovation Center, Zhanjiang, 524088, China
* Corresponding Authors: Ying Liu. Email: ; Yingbin Xue. Email:
(This article belongs to this Special Issue: Integrating Agronomy and Plant Physiology for Improving Crop Production)

Phyton-International Journal of Experimental Botany 2022, 91(5), 975-987. https://doi.org/10.32604/phyton.2022.019057

Received 31 August 2021; Accepted 08 October 2021; Issue published 24 January 2022

Abstract

In order to investigate the effects of Manganese (Mn) toxicity stress on the growth and gene expression at the seedling stage of soybean, soybean seedlings were treated with normal Mn concentration (5 μmol/L MnSO₄) and excess Mn concentration (100 μmol/L MnSO₄) by the method of hydroponic culture in this study. When soybean was subjected to Mn toxicity stress, excessive Mn could affect seedling growth, root development, the number of Mn oxide spots in leaves, and the Mn accumulation content in different parts of soybean. With the increase of exogenous Mn concentration and the prolongation of culture time, the shoot and root biomasses of soybean decreased significantly, but the plant height of soybean had no obvious effects. The total root length, root surface area and root volume of soybean decreased significantly, but the taproot length, taproot tip length and root diameter did not change significantly. The number of Mn spots in the primary leaves (first leaf) was significantly more than that in the old leaves (second leaf) and the youngest leaves (fourth leaf). The Mn concentration in leaves was significantly higher than that in roots, and the Mn concentration in the old leaves was significantly higher than that in youngest leaves with the method of inductively coupled plasma atomic emission spectrometry (ICP-AES). Moreover, the results in the present study suggested that the 10 selected genes were significantly up-regulated or down-regulated by Mn toxicity in the old and young leaves by quantitative real-time PCR (qRT-PCR) analysis. This indicates that these genes might be important in the process of regulation in old and young leaves of the physiological responses and ion transporting to Mn toxicity stress.

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Keywords

Manganese toxicity; soybean; gene expression

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