title: Effect of ultraviolet-B radiation in laboratory on morphological and ultrastructural characteristics and physiological parameters of selected cultivar of Oryza sativa L.
abstract: Ultraviolet-B radiation (UVBR) affects plants in many important ways, including reduction of growth rate and primary productivity, and changes in ultrastructures. Rice (Oryza sativa) is one of the most cultivated cereals in the world, along with corn and wheat, representing over 50% of agricultural production. In this study, we examined O. sativa plants exposed to ambient outdoor radiation and laboratory-controlled photosynthetically active radiation (PAR) and PAR + UVBR conditions for 2 h/day during 30 days of cultivation. The samples were studied for morphological and ultrastructural characteristics, and physiological parameters. PAR + UVBR caused changes in the ultrastructure of leaf of O. sativa and leaf morphology (leaf index, leaf area and specific leaf area, trichomes, and papillae), plant biomass (dry and fresh weight), photosynthetic pigments, phenolic compounds, and protein content. As a photoprotective acclimation strategy against PAR + UVBR damage, an increase of 66.24% in phenolic compounds was observed. Furthermore, PAR + UVBR treatment altering the levels of chlorophylls a and b, and total chlorophyll. In addition, total carotenoid contents decreased after PAR + UVBR treatment. The results strongly suggested that PAR + UVBR negatively affects the ultrastructure, morphology, photosynthetic pigments, and growth rates of leaf of O. sativa and, in the long term, it could affect the viability of this economically important plant.
authors.affiliation: Post-Graduate Program in Cell Biology and Development, Department of Cell Biology, Embryology and Genetics, Federal University of Santa Catarina, 88049-900, CP 476, Florianópolis, SC, Brazil.
authors.forename: Sérgio L
authors.initials: SL
authors.lastname: de Almeida
authors.forename: Éder C
authors.initials: ÉC
authors.lastname: Schmidt
authors.forename: Debora Tomazi
authors.initials: DT
authors.lastname: Pereira
authors.forename: Marianne
authors.initials: M
authors.lastname: Kreusch
authors.forename: Marthiellen R de L
authors.initials: MR
authors.lastname: Felix
authors.forename: Luz K P
authors.initials: LK
authors.lastname: Osorio
authors.forename: Roberta
authors.initials: R
authors.lastname: de Paula Martins
authors.forename: Alexandra
authors.initials: A
authors.lastname: Latini
authors.forename: Fernanda
authors.initials: F
authors.lastname: Ramlov
authors.forename: Fungyi
authors.initials: F
authors.lastname: Chow
authors.forename: Marcelo
authors.initials: M
authors.lastname: Maraschin
authors.forename: Ana C
authors.initials: AC
authors.lastname: Rodrigues
authors.forename: Zenilda L
authors.initials: ZL
authors.lastname: Bouzon
mesh_terms: D012275:Oryza / Q000502:physiology* / Q000528:radiation effects / Q000648:ultrastructure*; D010788:Photosynthesis / Q000528:radiation effects; D010860:Pigments, Biological / Q000378:metabolism; D019441:Plant Epidermis / Q000166:cytology / Q000528:radiation effects / Q000648:ultrastructure; D018515:Plant Leaves / Q000033:anatomy & histology / Q000528:radiation effects; D010940:Plant Proteins / Q000378:metabolism; D059808:Polyphenols / Q000378:metabolism; D012995:Solubility; D014466:Ultraviolet Rays
chemical_list: D010860:Pigments, Biological; D010940:Plant Proteins; D059808:Polyphenols