title: The effects of different UV-B radiation intensities on morphological and biochemical characteristics in Ocimum basilicum L.
abstract: BACKGROUND
  The effects of short-term ultraviolet B (UV-B) irradiation on sweet basil (Ocimum basilicum L. cv. Cinnamon) plants at the 3-4 leaf pair and flowering stages were examined in controlled environment growth chambers. Plants were exposed to 0 (reference), 2 and 4 kJ UV-B m(-2) day(-1) over 7 days.
  
  
  RESULTS
  Exposure of basil plants to supplementary UV-B light resulted in increased assimilating leaf area, fresh biomass and dry biomass. Stimulation of physiological functions in young basil plants under either applied UV-B dose resulted in increased total chlorophyll content but no marked variation in carotenoid content. At the flowering stage the chlorophyll and carotenoid contents of basil were affected by supplementary UV-B radiation, decreasing with enhanced UV-B exposure. Both total antioxidant activity (2,2-diphenyl-1-picrylhydrazyl free radical assay) and total phenolic compound content were increased by UV-B light supplementation. Young and mature basil plants differed in their ascorbic acid content, which was dependent on UV-B dose and plant age. UV-B radiation resulted in decreased nitrate content in young basil plants (3-4 leaf pair stage).
  
  
  CONCLUSIONS
  These results indicate that the application of short-exposure UV-B radiation beneficially influenced both growth parameters and biochemical constituents in young and mature basil plants.
authors.affiliation: Institute of Horticulture, Lithuanian Research Centre for Agriculture and Forestry, Babtai, Kaunas District, Lithuania. j.sakalauskaite@lsdi.lt
authors.forename: Jurga
authors.initials: J
authors.lastname: Sakalauskaitė
authors.forename: Pranas
authors.initials: P
authors.lastname: Viskelis
authors.forename: Edita
authors.initials: E
authors.lastname: Dambrauskienė
authors.forename: Sandra
authors.initials: S
authors.lastname: Sakalauskienė
authors.forename: Giedrė
authors.initials: G
authors.lastname: Samuolienė
authors.forename: Aušra
authors.initials: A
authors.lastname: Brazaitytė
authors.forename: Pavelas
authors.initials: P
authors.lastname: Duchovskis
authors.forename: Dalia
authors.initials: D
authors.lastname: Urbonavičienė
mesh_terms: D000975:Antioxidants / Q000378:metabolism*; D001205:Ascorbic Acid / Q000378:metabolism; D018533:Biomass; D001713:Biphenyl Compounds / Q000378:metabolism; D002338:Carotenoids / Q000378:metabolism; D002734:Chlorophyll / Q000378:metabolism*; D035264:Flowers; D009566:Nitrates / Q000378:metabolism; D009584:Nitrogen / Q000378:metabolism; D018649:Ocimum basilicum / Q000254:growth & development / Q000378:metabolism / Q000528:radiation effects*; D010636:Phenols / Q000378:metabolism; D064209:Phytochemicals / Q000378:metabolism*; D010851:Picrates / Q000378:metabolism; D063245:Plant Development / Q000502:physiology / Q000528:radiation effects; D018515:Plant Leaves / Q000254:growth & development / Q000378:metabolism / Q000528:radiation effects*; D014466:Ultraviolet Rays
chemical_list: D000975:Antioxidants; D001713:Biphenyl Compounds; D009566:Nitrates; D010636:Phenols; D064209:Phytochemicals; D010851:Picrates; D002734:Chlorophyll; D002338:Carotenoids; C004931:1,1-diphenyl-2-picrylhydrazyl; D009584:Nitrogen; D001205:Ascorbic Acid