Salah Sheteiwy Mohamed, Yajing Guan, Dongdong Cao, Jie Li, Aamir Nawaz, Qijuan Hu, Weimin Hu, Mingyu Ning, Jin Hu
Seed Science Center, College of Agriculture and Biotechnology, Zhejiang University, Hangzhou 310058, China.
Department of Agronomy, Faculty of Agriculture, Mansoura University, Mansoura 35516, Egypt.
Sci Rep. 2015 Sep 30;5:14278. doi: 10.1038/srep14278.
The present study was designed to highlight the impact of seed priming with polyethylene glycol on physiological and molecular mechanism of two cultivars of Oryza sativa L. under different levels of zinc oxide nanorods (0, 250, 500 and 750 mg L(-1)). Plant growth parameters were significantly increased in seed priming with 30% PEG under nano-ZnO stress in both cultivars. Whereas, this increase was more prominent in cultivar Qian You No. 1 as compared to cultivar Zhu Liang You 06. Significant increase in photosynthetic pigment with PEG priming under stress. Antioxidant enzymes activities of superoxide dismutase (SOD), peroxidase (POD) and catalase (CAT) as well as malondialdehyde (MDA) contents were significantly reduced with PEG priming under nano-ZnO stress. Gene expression analysis also suggested that expression of APXa, APXb, CATa, CATb, CATc, SOD1, SOD2 and SOD3 genes were down regulated with PEG priming as compared to non-primed seeds under stress. The ultrastructural analysis showed that leaf mesophyll and root cells were significantly damaged under nano-ZnO stress in both cultivars but the damage was prominent in Zhu Liang You 06. However, seed priming with PEG significantly alleviate the toxic effects of nano-ZnO stress and improved the cell structures of leaf and roots in both cultivars.
本研究旨在突出用聚乙二醇进行种子引发对两个水稻品种在不同水平氧化锌纳米棒（0、250、500和750 mg L⁻¹）下生理和分子机制的影响。在纳米氧化锌胁迫下，两个品种用30%聚乙二醇进行种子引发后，植株生长参数均显著增加。然而，与株两优06相比，这种增加在钱优一号品种中更为显著。在胁迫下，聚乙二醇引发使光合色素显著增加。在纳米氧化锌胁迫下，聚乙二醇引发显著降低了超氧化物歧化酶（SOD）、过氧化物酶（POD）和过氧化氢酶（CAT）等抗氧化酶活性以及丙二醛（MDA）含量。基因表达分析还表明，与胁迫下未引发的种子相比，聚乙二醇引发使APXa、APXb、CATa、CATb、CATc、SOD1、SOD2和SOD3基因的表达下调。超微结构分析表明，在纳米氧化锌胁迫下，两个品种的叶片叶肉和根细胞均受到显著损伤，但在株两优06中损伤更为突出。然而，聚乙二醇种子引发显著减轻了纳米氧化锌胁迫的毒性作用，并改善了两个品种叶片和根的细胞结构。
