{"title":"Cyanobacteria and Glutathione Applications Improve Productivity, Nutrient Contents, and Antioxidant Systems of Salt-Stressed Soybean Plant","authors":"S. S. Zaki, E. Belal, M. Rady","doi":"10.18052/WWW.SCIPRESS.COM/ILNS.76.72","DOIUrl":null,"url":null,"abstract":"Salt stress restricts plant performance by disrupting various physio-biochemical processes like photosynthesis. Plants growing in saline substrates show deficiencies in absorption of some essential elements due to the presence of excessive sodium (Na+) in the rhizosphere, which antagonizes beneficial cations and causing toxicity in metabolism. Cyanobacteria (CB; a natural biofertilizer) play a fundamental role in building-up soil fertility, thus increasing plant performance. Glutathione (GSH) is a well-known antioxidant, which contributes to increase salt tolerance in the plant. This work was conducted as a pot experiment (sand culture) in 2017 to study the combined effect of CB, applied as seed inoculation, and GSH, applied as foliar spray, on growth, pods and seed yields, the contents of antioxidants, osmoprotectants, and nutrients, and the antioxidative enzymes activities of soybean (Glycine max L., cv. Giza 111) plants grown under saline conditions. At fourth leaf stage (21 days after sowing; DAS), CB-pretreated seedlings were supplemented with NaCl (150 mM) along with Hoagland′s nutrient solution, and at the same time seedlings were sprayed with 1 mM GSH. Samples were taken at 60 DAS to assess morphological, physio-biochemical and antioxidant defense systems attributes. Results showed that the integrative application of CB and GSH under saline conditions was effective in improving significantly the growth characteristics, yield components, photosynthetic efficiency (pigments contents and chlorophyll fluorescence), membrane stability index, relative water content, contents of soluble sugars, free proline, ascorbic acid, glutathione, α-tocopherol, and protein, and activities of superoxide dismutase, catalase, and guaiacol peroxidase. The contents of macronutrients (N, P, K+, and Ca2+) were also increased significantly in Glycine max plants compared to the stressed control. In contrast, Na+ content and electrolyte leakage were significantly reduced. Our results recommend using the combined CB (as seed inoculation) and GSH (as foliar spray) application for soybean plantss to grow well under saline conditions.","PeriodicalId":14407,"journal":{"name":"International Letters of Natural Sciences","volume":null,"pages":null},"PeriodicalIF":0.3000,"publicationDate":"2019-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"7","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"International Letters of Natural Sciences","FirstCategoryId":"1085","ListUrlMain":"https://doi.org/10.18052/WWW.SCIPRESS.COM/ILNS.76.72","RegionNum":0,"RegionCategory":null,"ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"","JCRName":"","Score":null,"Total":0}
引用次数: 7
Abstract
Salt stress restricts plant performance by disrupting various physio-biochemical processes like photosynthesis. Plants growing in saline substrates show deficiencies in absorption of some essential elements due to the presence of excessive sodium (Na+) in the rhizosphere, which antagonizes beneficial cations and causing toxicity in metabolism. Cyanobacteria (CB; a natural biofertilizer) play a fundamental role in building-up soil fertility, thus increasing plant performance. Glutathione (GSH) is a well-known antioxidant, which contributes to increase salt tolerance in the plant. This work was conducted as a pot experiment (sand culture) in 2017 to study the combined effect of CB, applied as seed inoculation, and GSH, applied as foliar spray, on growth, pods and seed yields, the contents of antioxidants, osmoprotectants, and nutrients, and the antioxidative enzymes activities of soybean (Glycine max L., cv. Giza 111) plants grown under saline conditions. At fourth leaf stage (21 days after sowing; DAS), CB-pretreated seedlings were supplemented with NaCl (150 mM) along with Hoagland′s nutrient solution, and at the same time seedlings were sprayed with 1 mM GSH. Samples were taken at 60 DAS to assess morphological, physio-biochemical and antioxidant defense systems attributes. Results showed that the integrative application of CB and GSH under saline conditions was effective in improving significantly the growth characteristics, yield components, photosynthetic efficiency (pigments contents and chlorophyll fluorescence), membrane stability index, relative water content, contents of soluble sugars, free proline, ascorbic acid, glutathione, α-tocopherol, and protein, and activities of superoxide dismutase, catalase, and guaiacol peroxidase. The contents of macronutrients (N, P, K+, and Ca2+) were also increased significantly in Glycine max plants compared to the stressed control. In contrast, Na+ content and electrolyte leakage were significantly reduced. Our results recommend using the combined CB (as seed inoculation) and GSH (as foliar spray) application for soybean plantss to grow well under saline conditions.
盐胁迫通过破坏光合作用等各种生理生化过程来限制植物的生长性能。由于根际存在过量的钠(Na+),生长在盐水基质中的植物对某些必需元素的吸收不足,这会拮抗有益的阳离子并导致代谢毒性。蓝藻(CB;一种天然生物肥料)在提高土壤肥力从而提高植物性能方面发挥着重要作用。谷胱甘肽(GSH)是一种众所周知的抗氧化剂,有助于提高植物的耐盐性。这项工作于2017年作为盆栽试验(砂培)进行,以研究CB(用作种子接种)和GSH(用作叶面喷雾)对大豆(Glycine max L.,cv.Giza 111)在盐水条件下生长的生长、荚和种子产量、抗氧化剂、渗透保护剂和营养素的含量以及抗氧化酶活性的联合影响。在第四叶期(播种后21天;DAS),用NaCl(150mM)和Hoagland的营养液补充CB预处理的幼苗,同时用1mM GSH喷洒幼苗。在60个DAS处采集样本,以评估形态学、生理生化和抗氧化防御系统的属性。结果表明,在生理盐水条件下,CB和GSH的综合施用能显著改善作物的生长特性、产量组成、光合效率(色素含量和叶绿素荧光)、膜稳定性指数、相对含水量、可溶性糖、游离脯氨酸、抗坏血酸、谷胱甘肽、α-生育酚和蛋白质含量,以及超氧化物歧化酶、过氧化氢酶和愈创木酚过氧化物酶的活性。与胁迫对照相比,大豆植株的大量营养素(N、P、K+和Ca2+)含量也显著增加。相反,Na+含量和电解质泄漏显著降低。我们的研究结果建议使用CB(作为种子接种)和GSH(作为叶面喷雾)联合施用,使大豆植株在盐碱条件下生长良好。