脱硫废弃物对碱胁迫下油葵幼叶细胞钙分布及Ca2+-ATPase活性的影响

利用脱硫废弃物改良盐碱地对于确保国家粮食安全和生态安全,发展循环经济具有重要意义。为了探索脱硫废弃物提高植物抗盐碱机理,采用盆栽试验法, 研究了施入不同量脱硫废弃物和CaSO₄对碱胁迫下油葵叶片细胞钙分布、总钙含量以及质膜和液泡膜Ca²⁺-ATPase活性的影响。结果表明:在碱胁迫下(CK),Ca²⁺与焦锑酸钾结合成黑色颗粒成团零星分布于叶绿体和液泡中,叶绿体超微结构受到不同程度的破坏。施入脱硫废弃物和CaSO₄,叶绿体结构完整,细胞间隙、细胞壁和液泡中的钙颗粒逐渐增多,同时,质膜和液泡膜Ca²⁺-ATPase活性随脱硫废弃物和纯品硫酸钙施量的增加而增加,其中液泡膜Ca²⁺-ATPase活性无论是对照(CK)还是处理的活性均高于质膜Ca²⁺-ATPase活性。叶片细胞内总钙含量也随脱硫废弃物和CaSO₄施用量的增加呈升高趋势。说明脱硫废弃物和CaSO₄通过增加Ca²⁺-ATPase活性,有利于钙通过质膜和液泡膜进入细胞内,维持膜结构的稳定性,缓解碱对油葵的胁迫。

Effects of desulfurization waste treatment on calcium distribution and calcium ATPase activity in oil-sunflower seedlings under alkaline stress

Soil salinity is one of the major limiting factors in agricultural productivity. Desulfurization waste could be recycled to improve saline-alkaline soil, and this could provide stability in food production. In this study, desulfurization waste was applied to oil-sunflower seedlings to improve their resistance to saline-alkaline conditions. The distribution of calcium, total calcium content, and calcium ATPase (Ca²⁺-ATPase) activities in leaves cells were measured after exogenous treatment with desulfurization waste or calcium sulfate (CaSO₄). In control experiments under alkaline stress, there were few calcium precipitates in the chloroplast and vacuole, and the chloroplast structure was deformed. Calcium precipitates increased in the cell wall, intercellular space and vacuole, and the chloroplast structure remained intact after applying desulfurization gypsum or CaSO₄ to the sunflowers. The Ca²⁺-ATPase activities in the plasma membrane and tonoplast increased with the desulfurization waste or CaSO₄ dose, and activity was higher in the tonoplast than in the plasma membrane. The total calcium content also increased with the treatment dose. Both desulfurization waste and CaSO₄ contributed to calcium influx into the cell through the plasma membrane and tonoplast, which maintained the stability and integrity of the membrane and cell wall structure and reduced injury to the sunflower under alkaline stress.