Abd El-Mageed Taia A, Gyushi Mohammed A H, Hemida Khaulood A, El-Saadony Mohamed T, Abd El-Mageed Shimaa A, Abdalla Hanan, AbuQamar Synan F, El-Tarabily Khaled A, Abdelkhalik Abdelsattar
Department of Soil and Water, Faculty of Agriculture, Fayoum University, Fayoum, Egypt.
Department of Horticulture, Faculty of Agriculture, Fayoum University, Fayoum, Egypt.
Front Plant Sci. 2022 Jul 13;13:883274. doi: 10.3389/fpls.2022.883274. eCollection 2022.
The application of bio- and nanofertilizers are undoubtedly opening new sustainable approaches toward enhancing abiotic stress tolerance in crops. In this study, we evaluated the application of effective microorganisms (EMs) of five groups belonging to photosynthetic bacteria, lactic acid bacteria, yeast, actinobacteria, and fermenting fungi combined with magnesium oxide (MgO) nanoparticles (MgO-NP) on the growth and productivity of sweet potato plants grown in salt-affected soils. In two field experiments carried out in 2020 and 2021, we tested the impacts of EMs using two treatments (with vs. without EMs as soil drench) coupled with three foliar applications of MgO-NP (0, 50, and 100 μg ml of MgO, representing MgO-NP, MgO-NP, and MgO-NP, respectively). In our efforts to investigate the EMs:MgO-NP effects, the performance (growth and yield), nutrient acquisition, and physio-biochemical attributes of sweet potatoes grown in salt-affected soil (7.56 dS m) were assessed. Our results revealed that salinity stress significantly reduced the growth parameters, yield traits, photosynthetic pigment content (chlorophylls and , and carotenoids), cell membrane stability, relative water content, and nutrient acquisition of sweet potatoes. However, the EMs and/or MgO-NP-treated plants showed high tolerance to salt stress, specifically with a relatively superior increase when any of the biostimulants were combined. The application of EMs and/or MgO-NP improved osmotic stress tolerance by increasing the relative water content and membrane integrity. These positive responses owed to increase the osmolytes level (proline, free amino acids, and soluble sugars) and antioxidative compounds (non-enzymatic concentration, enzymatic activities, phenolic acid, and carotenoids). We also noticed that soil salinity significantly increased the Na content, whereas EMS and/or MgO-NP-treated plants exhibited lower Na concentration and increased K concentration and K/Na ratio. These improvements contributed to increasing the photosynthetic pigments, growth, and yield under salinity stress. The integrative application of EMs and MgO-NP showed higher efficacy bypassing all single treatments. Our findings indicated the potential of coapplying EMs and MgO-NP for future use in attenuating salt-induced damage beneficially promoting crop performance.
生物肥料和纳米肥料的应用无疑为提高作物对非生物胁迫的耐受性开辟了新的可持续途径。在本研究中，我们评估了光合细菌、乳酸菌、酵母、放线菌和发酵真菌这五类有效微生物（EMs）与氧化镁（MgO）纳米颗粒（MgO-NP）联合应用对盐渍土壤中种植的甘薯植株生长和生产力的影响。在2020年和2021年进行的两项田间试验中，我们测试了EMs的影响，采用两种处理方式（土壤浇灌含EMs与不含EMs），并结合三次叶面喷施MgO-NP（0、50和100μg/ml的MgO，分别代表MgO-NP、MgO-NP和MgO-NP）。为了研究EMs:MgO-NP的效果，我们评估了在盐渍土壤（7.56 dS m）中种植的甘薯的性能（生长和产量）、养分吸收以及生理生化特性。我们的结果表明，盐胁迫显著降低了甘薯的生长参数、产量性状、光合色素含量（叶绿素a和b以及类胡萝卜素）、细胞膜稳定性、相对含水量和养分吸收。然而，经EMs和/或MgO-NP处理的植株对盐胁迫表现出较高的耐受性，特别是当任何一种生物刺激剂联合使用时，其耐受性相对提高更为显著。EMs和/或MgO-NP的应用通过增加相对含水量和膜完整性提高了渗透胁迫耐受性。这些积极反应归因于渗透调节物质水平（脯氨酸、游离氨基酸和可溶性糖）和抗氧化化合物（非酶浓度、酶活性、酚酸和类胡萝卜素）的增加。我们还注意到，土壤盐分显著增加了钠含量，而经EMS和/或MgO-NP处理的植株钠浓度较低，钾浓度和钾/钠比增加。这些改善有助于在盐胁迫下增加光合色素、生长和产量。EMs和MgO-NP的综合应用显示出比所有单一处理更高的功效。我们的研究结果表明，联合应用EMs和MgO-NP在减轻盐害、有益地促进作物性能方面具有潜在的未来应用价值。
