Anhui Province Key Laboratory of Farmland Ecological Conservation and Pollution Prevention, School of Resources and Environment, Anhui Agricultural University, Hefei, China.
Environ Geochem Health. 2021 May;43(5):1855-1866. doi: 10.1007/s10653-020-00763-4. Epub 2020 Nov 6.
As an important class of flavonoids, anthocyanin has been used to enhance plant-defensive mechanisms against heavy metal stress. However, there are few available reports regarding surface spraying of anthocyanin for reduction of Cd poisoning in rice and its practical applications in paddy fields. After rice growing, measurements were taken of rice growth, pigments, the antioxidant system, thiol compounds, and distribution of Cd in rice tissues. The results showed that surface spraying anthocyanin could promote rice growth, and relative to the control, total chlorophyll significantly increased by 22.62% after surface spraying of 7.5 g L anthocyanin. Simultaneously, Cd accumulation in rice grains was 0.17 ± 0.02 mg kg, which was significantly decreased by 46.88% relative to the control. In the pot experiment (40-day-old rice), treatment with 7.5 g L anthocyanin resulted in decreases of ·O, HO, and malondialdehyde contents in rice leaves, while the activities of superoxide dismutase, peroxidase, catalase, and ascorbate peroxidase were increased by 59.10, 23.81, 41.75, and 9.39%, respectively. Meanwhile, contents of glutathione, ascorbic acid, non-protein thiols, and phytochelatins showed respective increases of 7.24, 14.49, 42.81, and 41.13% compared with the control value. Subcellular analysis revealed that surface spraying of anthocyanin increased organelle and soluble fractions of Cd in leaf cells. In conclusion, surface spraying of 7.5 g L anthocyanin was mainly attributed to increased antioxidant activities and subcellular sequestration of Cd in organelles and soluble fractions in rice leaves to reduce Cd accumulation in rice grains in the field.
作为类黄酮的重要成员，花色苷已被用于增强植物对重金属胁迫的防御机制。然而，关于叶面喷施花色苷来减轻水稻镉毒害及其在稻田实际应用的报道较少。在水稻生长后，测量了水稻的生长情况、色素、抗氧化系统、巯基化合物和镉在水稻组织中的分布。结果表明，叶面喷施花色苷可以促进水稻的生长，与对照相比，叶面喷施 7.5 g/L 花色苷后，总叶绿素含量显著增加了 22.62%。同时，糙米中 Cd 积累量为 0.17±0.02 mg/kg，与对照相比降低了 46.88%。在盆栽试验（40 日龄水稻）中，用 7.5 g/L 花色苷处理后，水稻叶片中·O、HO 和丙二醛含量降低，超氧化物歧化酶、过氧化物酶、过氧化氢酶和抗坏血酸过氧化物酶活性分别提高了 59.10%、23.81%、41.75%和 9.39%。同时，谷胱甘肽、抗坏血酸、非蛋白巯基和植物螯合肽的含量分别比对照值增加了 7.24%、14.49%、42.81%和 41.13%。亚细胞分析表明，叶面喷施花色苷增加了叶片细胞中细胞器和可溶性部分的 Cd 含量。综上所述，叶面喷施 7.5 g/L 花色苷主要归因于抗氧化活性的增加和 Cd 在细胞器和可溶性部分的亚细胞固定，从而减少了田间水稻糙米中 Cd 的积累。
