Zhang Zhong-Wei, Dong Yi-Ying, Feng Ling-Yang, Deng Zong-Lin, Xu Qiang, Tao Qi, Wang Chang-Quan, Chen Yang-Er, Yuan Ming, Yuan Shu
College of Life Science, Sichuan Agricultural University, Chengdu 611130, China.
College of Agronomy, Sichuan Agricultural University, Chengdu 611130, China.
Plants (Basel). 2020 Jul 17;9(7):904. doi: 10.3390/plants9070904.
Oilseed rape () is a Cadmium (Cd) hyperaccumulator. However, high-level Cd at the early seedling stage seriously arrests the growth of rape, which limits its applications. had higher Cd accumulation capacity, but its biomass was lower, also limiting its applications. Previous studies have confirmed that Selenium (Se) can alleviate Cd toxicity. However, the regulatory mechanism of Se in different valence states of Cd accumulation was unclear. In this study, we investigated the ameliorating effects of three Se valence states, NaSeO [Se(VI)], NaSeO [Se(IV)] and Se-Met [Se(II)], to Cd toxicity by physiological and biochemical approaches in hydroponically-cultured and seedlings. Although Se treatments slightly inhibited seedling Cd concentration, it tripled or quadrupled the Cd accumulation level per plant, because dry weight increased about four times more with Se and Cd application than with Cd treatment alone. Among the different valence states of Se, Se(II) had the most marked effect on reducing Cd toxicity as evidenced by decreased growth inhibition and Cd content. The application of Se(II) was effective in reducing Cd-induced reactive oxygen species accumulation, and promoted the antioxidant enzyme activity and photosynthesis of both species. In addition, Se(II) treatment increased the concentrations of Cd in the cell wall and soluble fractions, but the Cd concentration in the organelle part was reduced.
油菜（）是一种镉（Cd）超积累植物。然而，幼苗期高水平的镉严重阻碍油菜生长，限制了其应用。具有较高的镉积累能力，但其生物量较低，也限制了其应用。先前的研究证实，硒（Se）可以减轻镉毒性。然而，不同价态的硒对镉积累的调控机制尚不清楚。在本研究中，我们通过水培和幼苗的生理生化方法，研究了三种硒价态，即亚硒酸钠[Se(VI)]、亚硒酸钠[Se(IV)]和硒代蛋氨酸[Se(II)]对镉毒性的改善作用。尽管硒处理略微抑制了幼苗镉浓度，但它使单株镉积累水平增加了两倍或四倍，因为与单独镉处理相比，同时施用硒和镉时干重增加了约四倍。在不同价态的硒中，Se(II)对降低镉毒性的作用最为显著，表现为生长抑制和镉含量降低。施用Se(II)有效减少了镉诱导的活性氧积累，并促进了两种植物的抗氧化酶活性和光合作用。此外，Se(II)处理增加了细胞壁和可溶性部分中的镉浓度，但细胞器部分中的镉浓度降低。
