title: Effect of nitrogen fertilisation and irrigation on phenolic content, phenolic acid composition, and antioxidant activity of winter wheat grain.
abstract: BACKGROUND
  Understanding the variance of antioxidant in wheat grain responses to irrigation and nitrogen (N) fertiliser management will improve the nutrient quality of wheat grain. Four N rates (0, 180, 240, and 300 kg ha(-1)) combined with irrigation times (I0, no irrigation; I1, jointing time irrigation; I2, jointing + flowering time irrigation), were used to determine the effect of N fertilisation and irrigation on total phenolic content (TPC), phenolic acid composition, and antioxidant activity (AOA) of wheat grain.
  
  
  RESULTS
  Irrigation, N fertilisation and their interactions had significant effect on TPC, total flavonoid content (TFC), AOA, p-coumaric acid (PCA), as well as vanillic acid (VA) and chlorogenic acid (CA). I1 N300 treatment had the highest TPC at Zhengzhou and Wenxian (1451.5 µg g(-1) and 1397.9 µg g(-1), respectively) location, while I1 N240 resulted in the highest TFC (0.75 mg g(-1)) and VA (19.77 µg g(-1)) at Wenxian. TPC, TFC, AOA, ferulic acid (FA), PCA and VA increased with N application rate (from 180 to 300 kg N ha(-1)).
  
  
  CONCLUSIONS
  An appropriate irrigation and N management improved antioxidant content and AOA in wheat grain. Generally, I1 N240 and I1 N300 treatment resulted in the higher TPC, TFC, AOA, as well as phenolic acid, i.e. FA and VA.
authors.affiliation: National Engineering Research Center for Wheat, Henan Agricultural University, Zhengzhou, Henan, 450002, China; Key Laboratory of Physiology, Ecology and Genetic Improve of Food Crops in Henan Province, Zhengzhou, Henan, 450002, China.
authors.forename: Dongyun
authors.initials: D
authors.lastname: Ma
authors.forename: Dexiang
authors.initials: D
authors.lastname: Sun
authors.forename: Yaoguang
authors.initials: Y
authors.lastname: Li
authors.forename: Chenyang
authors.initials: C
authors.lastname: Wang
authors.forename: Yingxin
authors.initials: Y
authors.lastname: Xie
authors.forename: Tiancai
authors.initials: T
authors.lastname: Guo
mesh_terms: D057914:Agricultural Irrigation; D000975:Antioxidants / Q000032:analysis / Q000378:metabolism*; D002681:China; D002726:Chlorogenic Acid / Q000032:analysis / Q000378:metabolism; D003373:Coumaric Acids / Q000032:analysis / Q000378:metabolism; D018556:Crops, Agricultural / Q000737:chemistry / Q000254:growth & development* / Q000378:metabolism; D005308:Fertilizers; D005419:Flavonoids / Q000032:analysis / Q000096:biosynthesis; D062385:Hydroxybenzoates / Q000032:analysis / Q000378:metabolism; D017672:Nitrogen Compounds / Q000378:metabolism; D058458:Nitrogen Cycle; D010636:Phenols / Q000032:analysis / Q000378:metabolism; D064209:Phytochemicals / Q000096:biosynthesis* / Q000378:metabolism; D011422:Propionates; D012621:Seasons; D012639:Seeds / Q000737:chemistry / Q000254:growth & development / Q000378:metabolism*; D014908:Triticum / Q000737:chemistry / Q000254:growth & development / Q000378:metabolism*; D015854:Up-Regulation; D014641:Vanillic Acid / Q000032:analysis / Q000378:metabolism; D014887:Weather
chemical_list: D000975:Antioxidants; D003373:Coumaric Acids; D005308:Fertilizers; D005419:Flavonoids; D062385:Hydroxybenzoates; D017672:Nitrogen Compounds; D010636:Phenols; D064209:Phytochemicals; D011422:Propionates; D002726:Chlorogenic Acid; D014641:Vanillic Acid; C017616:phenolic acid; C495469:p-coumaric acid
keywords: antioxidant activity; irrigation and nitrogen management; phenolic acid; total phenolic content; wheat