Chatterjee Poulami, Samaddar Sandipan, Anandham Rangasamy, Kang Yeongyeong, Kim Kiyoon, Selvakumar Gopal, Sa Tongmin
Department of Environmental and Biological Chemistry, Chungbuk National UniversityCheongju, South Korea.
Department of Agricultural Microbiology, Agricultural College and Research Institute, Tamil Nadu Agricultural UniversityMadurai, India.
Front Plant Sci. 2017 May 4;8:705. doi: 10.3389/fpls.2017.00705. eCollection 2017.
Soil salinity, being a part of natural ecosystems, is an increasing problem in agricultural soils throughout the world. OS261 has already been proved to be an effective bio-inoculant for enhancing cold stress tolerance in plants, however, its effect on salt stress tolerance is unknown. The main aim of the present study was to elucidate OS261 mediated salt stress tolerance in red pepper. The plants were exposed to a salt stress using NaCl at the concentrations of 50, 100, and 150 mM after 12 days of transplantation, while plant growth and enzyme activity were estimated 50 days after sowing. The height in . OS261 inoculated plants was significantly increased by 19.05, 34.35, 57.25, and 61.07% compared to un-inoculated controls at 0, 50, 100, and 150 mM of NaCl concentrations, respectively, under greenhouse conditions. The dry biomass of the plants increased by 31.97, 37.47, 62.67, and 67.84% under 0, 50, 100, and 150 mM of NaCl concentrations, respectively. A high emission of ethylene was observed in un-inoculated red pepper plants under salinity stress. . OS261 inoculation significantly reduced ethylene emission by 20.03, 18.01, and 20.07% at 50, 100, and 150 mM of NaCl concentrations, respectively. Furthermore, the activity of antioxidant enzymes (ascorbate peroxidase, superoxide dismutase, and catalase) also varied in the inoculated red pepper plants. Salt stress resistance in the bacterized plants was evident from the improved antioxidant activity in leaf tissues and the decreased hydrogen ion concentration. Thus, we conclude that . OS261 possesses stress mitigating property which can enhance plant growth under high soil salinity by reducing the emission of ethylene and regulating antioxidant enzymes.
土壤盐分作为自然生态系统的一部分，在全球农业土壤中已成为一个日益严重的问题。OS261已被证明是一种有效的生物接种剂，可增强植物的冷胁迫耐受性，然而，其对盐胁迫耐受性的影响尚不清楚。本研究的主要目的是阐明OS261介导的红辣椒盐胁迫耐受性。在移植12天后，使用浓度为50、100和150 mM的NaCl对植株施加盐胁迫，而在播种50天后评估植株生长和酶活性。在温室条件下, 与未接种对照相比，接种OS261的植株在NaCl浓度分别为0、50、100和150 mM时，株高显著增加了19.05%、34.35%、57.25%和61.07%。在0、50、100和150 mM的NaCl浓度下，植株的干生物量分别增加了31.97%、37.47%、62.67%和67.84%。在盐胁迫下，未接种的红辣椒植株中观察到乙烯的高释放量。接种OS261分别使50、100和150 mM NaCl浓度下的乙烯释放量显著降低了20.03%、18.01%和20.07%。此外，接种的红辣椒植株中抗氧化酶（抗坏血酸过氧化物酶、超氧化物歧化酶和过氧化氢酶）的活性也有所不同。接种细菌的植株的耐盐性从叶组织中抗氧化活性的提高和氢离子浓度的降低中明显体现出来。因此, 我们得出结论，OS261具有减轻胁迫的特性，可通过减少乙烯释放和调节抗氧化酶来提高高土壤盐分条件下的植物生长。
