title: Heat stress causes alterations in the cell-wall polymers and anatomy of coffee leaves (Coffea arabica L.).
abstract: Coffee plants were subjected to heat stress (37 °C) and compared with control plants (24 °C). Cell wall polysaccharides were extracted using water (W), EDTA (E) and 4M NaOH (H30 and H70). In addition, monolignols were analyzed, and the leaves were observed by microscopy. Plants under heat stress accumulated higher contents of arabinose and galactose in fraction W. Xylose contents were observed to decrease in H30 fractions after the heat stress, whereas galactose and uronic acid increased. H70 fractions from plants exposed to heat stress showed increased xylose contents, whereas the contents of arabinose and glucose decreased. Differences in the molar-mass profiles of polysaccharides were also observed. The primary monolignol contents increased after the heat stress. Structural alterations in palisade cells and ultrastructural damage in chloroplasts were also observed. Our results demonstrate that the chemical profile of coffee cell-wall polymers and structural cell anatomy change under heat stress.
authors: Departamento de Bioquímica e Biologia Molecular, Universidade Federal do Paraná, CP 19046, 81531-980 Curitiba, PR, Brazil.
authors: Rogério Barbosa
authors: RB
authors: Lima
authors: Tiago Benedito
authors: TB
authors: dos Santos
authors: Luiz Gonzaga Esteves
authors: LG
authors: Vieira
authors: Maria de Lourdes Lúcio
authors: Mde L
authors: Ferrarese
authors: Osvaldo
authors: O
authors: Ferrarese-Filho
authors: Lucélia
authors: L
authors: Donatti
authors: Maria Regina Torres
authors: MR
authors: Boeger
authors: Carmen Lúcia de Oliveira
authors: CL
authors: Petkowicz
mesh_terms: D001089:Arabinose / Q000737:chemistry; D002473:Cell Wall / Q000737:chemistry*; D002850:Chromatography, Gel / Q000379:methods; D040503:Coffea / Q000033:anatomy & histology / Q000737:chemistry*; D005685:Galactans / Q000737:chemistry; D006358:Hot Temperature; D008031:Lignin / Q000737:chemistry; D010368:Pectins / Q000737:chemistry; D059828:Plant Cells / Q000737:chemistry; D018515:Plant Leaves / Q000033:anatomy & histology*; D011134:Polysaccharides / Q000737:chemistry; D013312:Stress, Physiological; D014574:Uronic Acids / Q000737:chemistry; D014867:Water / Q000737:chemistry
chemical_list: D005685:Galactans; D011134:Polysaccharides; D014574:Uronic Acids; D014867:Water; D010368:Pectins; D008031:Lignin; D001089:Arabinose; C005653:arabinogalactan