Inhibition of Nitrogen and Photosynthetic Carbon Assimilation of Maize Seedlings by Exposure to a Combination of Salt Stress and Potassium-Deficient Stress
Inhibition of Nitrogen and Photosynthetic Carbon Assimilation of Maize Seedlings by Exposure to a Combination of Salt Stress and Potassium-Deficient Stress
复制标题
盐胁迫和缺钾胁迫组合对玉米幼苗氮和光合碳同化的抑制
DOI：
10.1007/s12011-011-9037-6
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发表时间：
2011-12-01
影响因子：
3.9
通讯作者：
Hong, Fashui
中科院分区：
文献类型：
--
作者：
Qu, Chunxiang;Liu, Chao;Hong, Fashui
这项工作的主要目的是确定组合胁迫如何影响玉米中相互依赖的氮和光合碳同化。玉米植物在迈德溶液中栽培。他们在存在钾的迈德培养基和缺乏钾的迈德培养基中遭受盐胁迫和钾缺乏。 5周后，我们测量了叶绿素a荧光以及协调玉米叶子中初级氮和碳同化的代谢检查点中的几种酶的活性。研究表明，盐胁迫和缺钾胁迫的组合更显着地降低硝酸盐吸收、植物生长、硝酸还原酶、谷氨酸脱氢酶、谷氨酸合酶、脲酶、谷氨酸-丙酮酸转氨酶、谷氨酸-草酰转氨酶、蔗糖-磷酸合酶、磷酸烯醇丙酮酸羧化酶的活性以及游离氨基酸、叶绿素和叶绿素的合成。分别比每个个体应激的蛋白质。然而，联合胁迫显着增加了铵和碳水化合物产物的积累。联合胁迫还显着降低了玉米幼苗中光系统 II 的氧气释放、电子传输和光化学能量转换效率。总而言之，盐胁迫和缺钾胁迫的结合损害了氮和碳的同化，并降低了玉米的光系统 II 活性。
The main aim of this work is to identify how the combined stresses affect the interdependent nitrogen and photosynthetic carbon assimilations in maize. Maize plants were cultivated in Meider's solution. They were subjected to salt stress and potassium deficiency in the K-present Meider's media and K-deficient Meider's media. After 5 weeks, we measured chlorophyll a fluorescence and the activities of several enzymes in metabolic checkpoints coordinating primary nitrogen and carbon assimilation in the leaves of maize. The study showed that the combination of salt stress and potassium-deficient stress more significantly decreased nitrate uptake, plant growth, the activities of nitrate reductase, glutamate dehydrogenase, glutamate synthase, urease, glutamic-pyruvic transaminase, glutamic-oxaloace transaminase, sucrose-phosphate synthase, phosphoenolpyruvate carboxylase, and the synthesis of free amino acids, chlorophyll, and protein than those of each individual stress, respectively. However, the combined stresses significantly increased the accumulation of ammonium and carbohydrate products. The combined stresses also significantly decreased the oxygen evolution, the electron transport, and the efficiency of photochemical energy conversion by photosystem II in maize seedlings. Taken together, a combination of salt stress and potassium-deficient stress impaired the assimilations of both nitrogen and carbon and decreased the photosystem II activity in maize.