title: Exogenous spermidine improves seed germination of sweet corn via involvement in phytohormone interactions, H2O2and relevant gene expression.
abstract: The low seed vigor and poor field emergence are main factors that restricting the extension of sweet corn in China. Spermidine (Spd) plays an important role in plant growth and development, but little is known about the effect of Spd on sweet corn seed germination. Therefore the effect of exogenous Spd on seed germination and physiological and biochemical changes during seed imbibition of Xiantian No.5 were investigated in this study.
  
  
  
  Spd soaking treatment not only improved seed germination percentage but also significantly enhanced seed vigor which was indicated by higher germination index, vigor index, shoot heights and dry weights of shoot and root compared with the control; while exogenous CHA, the biosynthesis inhibitor of Spd, significantly inhibited seed germination and declined seed vigor. Spd application significantly increased endogenous Spd, gibberellins and ethylene contents and simultaneously reduced ABA concentration in embryos during seed imbibition. In addition, the effects of exogenous Spd on H2O2and MDA productions were also analyzed. Enhanced H2O2concentration was observed in Spd-treated seed embryo, while no significant difference of MDA level in seed embryo was observed between Spd treatment and control. However, the lower H2O2and significantly higher MDA contents than control were detected in CHA-treated seed embryos.
  
  
  
  The results suggested that Spd contributing to fast seed germination and high seed vigor of sweet corn might be closely related with the metabolism of hormones including gibberellins, ABA and ethylene, and with the increase of H2O2in the radical produced partly from Spd oxidation. In addition, Spd might play an important role in cell membrane integrity maintaining.
authors.affiliation: Seed Science Center, Institute of Crop Science, College of Agriculture and Biotechnology, Zhejiang University, 866 Yuhangtang Road, Hangzhou, 310058, China.
authors.forename: Yutao
authors.initials: Y
authors.lastname: Huang
authors.affiliation: Seed Science Center, Institute of Crop Science, College of Agriculture and Biotechnology, Zhejiang University, 866 Yuhangtang Road, Hangzhou, 310058, China.
authors.forename: Cheng
authors.initials: C
authors.lastname: Lin
authors.affiliation: Seed Science Center, Institute of Crop Science, College of Agriculture and Biotechnology, Zhejiang University, 866 Yuhangtang Road, Hangzhou, 310058, China.
authors.forename: Fei
authors.initials: F
authors.lastname: He
authors.affiliation: Seed Science Center, Institute of Crop Science, College of Agriculture and Biotechnology, Zhejiang University, 866 Yuhangtang Road, Hangzhou, 310058, China.
authors.forename: Zhan
authors.initials: Z
authors.lastname: Li
authors.affiliation: Seed Science Center, Institute of Crop Science, College of Agriculture and Biotechnology, Zhejiang University, 866 Yuhangtang Road, Hangzhou, 310058, China. vcguan@zju.edu.cn.
authors.forename: Yajing
authors.initials: Y
authors.lastname: Guan
authors.affiliation: Seed Science Center, Institute of Crop Science, College of Agriculture and Biotechnology, Zhejiang University, 866 Yuhangtang Road, Hangzhou, 310058, China.
authors.forename: Qijuan
authors.initials: Q
authors.lastname: Hu
authors.affiliation: Seed Science Center, Institute of Crop Science, College of Agriculture and Biotechnology, Zhejiang University, 866 Yuhangtang Road, Hangzhou, 310058, China. jhu@zju.edu.cn.
authors.forename: Jin
authors.initials: J
authors.lastname: Hu
mesh_terms: D018506:Gene Expression Regulation, Plant / Q000187:drug effects*; D018525:Germination / Q000187:drug effects*; D006861:Hydrogen Peroxide / Q000378:metabolism*; D010937:Plant Growth Regulators / Q000378:metabolism*; D012639:Seeds / Q000187:drug effects* / Q000502:physiology; D013095:Spermidine / Q000494:pharmacology*; D003313:Zea mays / Q000187:drug effects* / Q000378:metabolism / Q000502:physiology
chemical_list: D010937:Plant Growth Regulators; D006861:Hydrogen Peroxide; D013095:Spermidine
keywords: Gene expression; H2O2; Phytohormone; Seed germination; Spermidine; Sweet corn