title: Silicon improves seed germination and alleviates oxidative stress of bud seedlings in tomato under water deficit stress.
abstract: The beneficial effects of silicon on plant growth and development under drought have been widely reported. However, little information is available on the effects of silicon on seed germination under drought. In this work, the effects of exogenous silicon (0.5 mM) on the seed germination and tolerance performance of tomato (Solanum lycopersicum L.) bud seedlings under water deficit stress simulated by 10% (w/v) polyethylene glycol (PEG-6000) were investigated in four cultivars ('Jinpengchaoguan', 'Zhongza No.9', 'Houpi L402' and 'Oubao318'). The results showed that the seed germination percentage was notably decreased in the four cultivars under water stress, and it was significantly improved by added silicon. Compared with the non-silicon treatment, silicon addition increased the activities of superoxide dismutase (SOD) and catalase (CAT), and decreased the production of superoxide anion (O2·) and hydrogen peroxide (H2O2) in the radicles of bud seedlings under water stress. Addition of silicon decreased the total phenol concentrations in radicles under water stress, which might contribute to the decrease of peroxidase (POD) activity, as observed in the in vivo and in vitro experiments. The decrease of POD activity might contribute to a less accumulation of hydroxyl radical (·OH) under water stress. Silicon addition also decreased the concentrations of malondialdehyde (MDA) in the radicles under stress, indicating decreased lipid peroxidation. These results suggest that exogenous silicon could improve seed germination and alleviate oxidative stress to bud seedling of tomato by enhancing antioxidant defense. The positive effects of silicon observed in a silicon-excluder also suggest the active involvement of silicon in biochemical processes in plants.
authors.affiliation: College of Horticulture, Northwest A&F University, Yangling 712100, Shaanxi, PR China.
authors.forename: Yu
authors.initials: Y
authors.lastname: Shi
authors.affiliation: College of Horticulture, Shanxi Agricultural University, Taigu 030801, Shanxi, PR China.
authors.forename: Yi
authors.initials: Y
authors.lastname: Zhang
authors.affiliation: College of Teacher Education, Quzhou University, Quzhou 324000, Zhejiang, PR China.
authors.forename: Hejin
authors.initials: H
authors.lastname: Yao
authors.affiliation: College of Horticulture, Northwest A&F University, Yangling 712100, Shaanxi, PR China.
authors.forename: Jiawen
authors.initials: J
authors.lastname: Wu
authors.affiliation: College of Horticulture, Northwest A&F University, Yangling 712100, Shaanxi, PR China.
authors.forename: Hao
authors.initials: H
authors.lastname: Sun
authors.affiliation: College of Horticulture, Northwest A&F University, Yangling 712100, Shaanxi, PR China. Electronic address: gongnavy@163.com.
authors.forename: Haijun
authors.initials: H
authors.lastname: Gong
mesh_terms: D000975:Antioxidants / Q000378:metabolism; D002374:Catalase / Q000378:metabolism; D003681:Dehydration; D018525:Germination / Q000187:drug effects*; D006861:Hydrogen Peroxide / Q000378:metabolism; D018551:Solanum lycopersicum / Q000187:drug effects* / Q000254:growth & development / Q000378:metabolism; D008315:Malondialdehyde / Q000378:metabolism; D018384:Oxidative Stress / Q000187:drug effects*; D019800:Phenol / Q000378:metabolism; D036226:Seedlings / Q000187:drug effects* / Q000254:growth & development / Q000378:metabolism; D012639:Seeds / Q000187:drug effects* / Q000254:growth & development / Q000378:metabolism; D012825:Silicon / Q000494:pharmacology*; D013482:Superoxide Dismutase / Q000378:metabolism; D013481:Superoxides / Q000378:metabolism; D013997:Time Factors; D014867:Water / Q000378:metabolism
chemical_list: D000975:Antioxidants; D014867:Water; D013481:Superoxides; D019800:Phenol; D008315:Malondialdehyde; D006861:Hydrogen Peroxide; D002374:Catalase; D013482:Superoxide Dismutase; D012825:Silicon
keywords: Antioxidant defense; Oxidative damage; Seed germination; Silicon; Tomato; Water deficit