Yasmin Humaira, Mazher Javeria, Azmat Ammar, Nosheen Asia, Naz Rabia, Hassan Muhammad Nadeem, Noureldeen Ahmed, Ahmad Parvaiz
Department of Biosciences, COMSATS University Islamabad (CUI), Islamabad, Pakistan.
Department of Biosciences, COMSATS University Islamabad (CUI), Islamabad, Pakistan.
Ecotoxicol Environ Saf. 2021 May 5;218:112262. doi: 10.1016/j.ecoenv.2021.112262.
Salinity is a key devastating abiotic factor that hinders the development and yield of safflower. The sole and combined application of zinc oxide nanoparticles (ZnO-NPs) and a biofertilizer (BF) to improve salt tolerance in safflower has not been thoroughly explored. The response of safflower plants in a pot experiment to the foliar spray of ZnO-NPs alone and in combination with a BF was thus detected. We determined that a ZnO-NP concentration of 17 mg/L was sufficient to protect safflower against salinity (250 mM NaCl) by increasing the plant productivity, percent water content, and osmolyte levels. Coapplication of ZnO-NPs and Phytoguard protected safflower plants from salinity stress by improving the activities of antioxidant enzymes and decreasing the levels of proline (leaves (61%) and roots (63%)) and malondialdehyde (MDA) (leaves (54%) and roots (65%)). Under salt stress, the Na content increased, while seed coating with biofertilizer and ZnO-NP spray significantly decreased the Na concentration (74% in leaves and 60% in roots). For the K concentration, however, antagonistic outcomes were observed. Additionally, the combined treatment significantly enhanced agronomic parameters such as the number of leaves and pods per plant, capitulum weight, and the number of yellow and wilted leaves per plant under salinity stress. Thus, ZnO-NPs could be an effective bio-source for the protection of safflower plants under salinity stress. Our findings showed that in the combined treatment of ZnO-NPs and biofertilizer, the salinity tolerance was more pronounced than in the single treatment and untreated control. A thorough analysis at the molecular level, however, is still required to understand the mechanism by which ZnO-NPs and BF in safflower plants alleviate salt stress.
盐度是阻碍红花生长发育和产量的关键非生物胁迫因素。氧化锌纳米颗粒（ZnO-NPs）和生物肥料（BF）单独及联合应用对提高红花耐盐性的研究尚未充分开展。因此，在盆栽试验中检测了红花植株对单独喷施ZnO-NPs以及与BF联合喷施的反应。我们确定，17 mg/L的ZnO-NP浓度足以通过提高植物生产力、含水量百分比和渗透物质水平来保护红花免受盐胁迫（250 mM NaCl）。ZnO-NPs与Phytoguard联合应用通过提高抗氧化酶活性、降低脯氨酸（叶片（61%）和根系（63%））和丙二醛（MDA）（叶片（54%）和根系（65%））水平，保护红花植株免受盐胁迫。在盐胁迫下，钠含量增加，而生物肥料包衣种子和喷施ZnO-NP显著降低了钠浓度（叶片中降低74%，根系中降低60%）。然而，对于钾浓度，观察到了拮抗作用。此外，联合处理显著提高了盐胁迫下的农艺参数，如单株叶片和豆荚数量、头状花序重量以及单株黄叶和枯萎叶数量。因此，ZnO-NPs可能是盐胁迫下保护红花植株的有效生物源。我们的研究结果表明，在ZnO-NPs与生物肥料的联合处理中，耐盐性比单一处理和未处理对照更为显著。然而仍需要在分子水平上进行深入分析，以了解红花植株中ZnO-NPs和BF缓解盐胁迫的机制。
