Djanaguiraman M, Belliraj N, Bossmann Stefan H, Prasad P V Vara
Department of Agronomy, Throckmorton Plant Science Center and Department of Chemistry, Kansas State University, Manhattan, Kansas 66506, United States.
Department of Nano Science and Technology, Tamil Nadu Agricultural University, Coimbatore, TN 641003, India.
ACS Omega. 2018 Mar 1;3(3):2479-2491. doi: 10.1021/acsomega.7b01934. eCollection 2018 Mar 31.
The role of selenium nanoparticles (Se-NPs) in the mitigation of high-temperature (HT) stress in crops is not known. The uptake, toxicity and physiological and biological effects of Se-NPs under HT were investigated in grain sorghum [ (L.) Moench]. Se-NPs of size 10-40 nm were synthesized and characterized to indicate nanocrystalline structure. A toxicity assay showed that Se-NPs concentration inducing 50% cell mortality (TC50) was 275 mg L. Translocation study indicated that Se-NPs can move from root to shoot of sorghum plants. Foliar spray of 10 mg L Se-NPs during the booting stage of sorghum grown under HT stress stimulated the antioxidant defense system by enhancing antioxidant enzymes activity. Furthermore, it decreased the concentration of signature oxidants. Se-NPs facilitated higher levels of unsaturated phospholipids. Se-NPs under HT stress improved the pollen germination percentage, leading to a significantly increased seed yield. The increased antioxidant enzyme activity and decreased content of oxidants in the presence of Se-NPs were greater under HT (38/28 °C) than under optimum temperature conditions (32/22 °C). In conclusion, Se-NPs can protect sorghum plants by enhanced antioxidative defense system under HT stress.
硒纳米颗粒（Se-NPs）在减轻作物高温（HT）胁迫方面的作用尚不清楚。本研究在粒用高粱[（L.）Moench]中调查了高温条件下Se-NPs的吸收、毒性以及生理和生物学效应。合成并表征了尺寸为10-40 nm的Se-NPs，以表明其纳米晶体结构。毒性试验表明，诱导50%细胞死亡率（TC50）的Se-NPs浓度为275 mg L。转运研究表明，Se-NPs可以从高粱植株的根部转移到地上部。在高温胁迫下生长的高粱孕穗期叶面喷施10 mg L Se-NPs，通过提高抗氧化酶活性刺激了抗氧化防御系统。此外，它降低了标志性氧化剂的浓度。Se-NPs促进了更高水平的不饱和磷脂。高温胁迫下的Se-NPs提高了花粉萌发率，导致种子产量显著增加。与最适温度条件（32/22°C）相比，高温（38/28°C）下Se-NPs存在时抗氧化酶活性增加和氧化剂含量降低的幅度更大。总之，Se-NPs可以通过增强高温胁迫下的抗氧化防御系统来保护高粱植株。
