High boron stress leads to sugar beet (Beta vulgaris L.) toxicity by disrupting photosystem Ⅱ

作者：Jialu Huo, Baiquan Song, Muhammad Riaz, Xin Song, Jiaxin Li, Huajun Liu, Wengong Huang, Qiue Jia, Wenyu Wu · 发表于：Ecotoxicology and Environmental Safety · 年份：2022 · DOI：10.1016/j.ecoenv.2022.114295 · 被引用次数：26 · 研究领域：Plant Micronutrient Interactions and Effects、Geochemistry and Elemental Analysis、Aluminum toxicity and tolerance in plants and animals

This sugar beet acts as a soil remediator in areas where there are high levels of boron (B) in the soil, since it has a high requirement of boron (B) for growth, and has strong resistance to high B levels. Although B toxicity in different plants has been widely researched, little is known about the response of photosystem II (PSII) activity in sugar beet leaves to B toxicity at present. To clarify the growth and photosynthetic physiological response of sugar beet to B toxicity, the effects of different concentrations of H3BO3 (0.05, 1.5, 2.5,3.5 mM) on the growth, photosynthetic characteristics and antioxidant defense system of sugar beet seedlings were investigated by hydroponic experiments. In the present study, high B stress inhibited the growth of sugar beet and significantly decreased the biomass of the plants. There was a remarkable increase in the accumulation of B in the shoots, which affected photosynthesis and decreased the photosynthetic pigments. As B toxicity increased, leaf PSII activities and maximum photochemical efficiency of PSII (Fv/Fm) showed a tendency to decrease; at the same time, the photosynthetic performance index based on absorbed light energy (PIABS) decreased as well. Meanwhile, the energy allocation parameters of the PSII reaction center were changed, the light energy utilization capacity and the energy used for electron transfer were reduced and the thermal dissipation was increased at the same time. Furthermore, B toxicity decreased catalase (C...