Cuticle biosynthesis in rapidly growing internodes of deepwater rice

• Published in: Plant physiology (Bethesda) Vol. 104; no. 2; pp. 719 - 723
• Main Authors: Hoffmann-Benning, S, Kende, H
• Format: Journal Article
• Language: English
• Published: Rockville, MD American Society of Plant Physiologists 01-02-1994
• Subjects: ACIDE OLEIQUE; ACIDE PALMITIQUE; ACIDO GIBERELICO; ACIDO OLEICO; ACIDO PALMITICO; ACTIVIDAD ENZIMATICA; ACTIVITE ENZYMATIQUE; Agronomy. Soil science and plant productions; Animal cuticle; Bending; BEURRE VEGETAL; Biological and medical sciences; BIOSINTESIS; BIOSYNTHESE; Biosynthesis; Cell walls; CELLULE; CELULAS; Chemical agents; CRECIMIENTO; CROISSANCE; Development and Growth Regulation; ENTRE NOEUD; ENZIMAS; ENZYME; Epidermal cells; Fatty acids; Fundamental and applied biological sciences. Psychology; GIBBERELLINE; GRASAS VEGETALES; INDICE DE CRECIMIENTO; INONDATION; Internodes; INTERNODIOS; INUNDACION; ORYZA SATIVA; PARED CELULAR; PAROI CELLULAIRE; Plant cuticle; Plant physiology and development; Plants; Rice; TAUX DE CROISSANCE; Vegetative apparatus, growth and morphogenesis. Senescence; Monocotyledones; Radiolabelling; Growth; Cuticle; Gibberellin; Biosynthesis; Growth regulator treatment; Palmitic acid; Cereal crop; Stress; Oryza sativa; Gramineae; Oleic acid; Angiospermae; Plant growth substance; Spermatophyta; Elongation
• ISSN: 0032-0889; 1532-2548
• DOI: 10.1104/pp.104.2.719

Submergence induces rapid elongation of deepwater rice (Oryza sativa L.) internodes. This adaptive feature allows deepwater rice to grow out of the water and to survive flooding. The growth response of submerged deepwater rice plants is, ultimately, elicited by gibberellin (GA). Little attention has been given to the synthesis and role of the cuticle during plant growth. We investigated two questions regarding the cuticle in rapidly elongating deepwater rice internodes: (a) how does cuticle formation keep pace with internodal growth, which can reach rates of up to 5 mm/h; and (b) does the cuticle contribute to tissue stress in rice internodes? Treatment with GA for 48 h caused an up to 60-fold increase in the incorporation of [14C] palmitic acid and an up to 6-fold increase in the incorporation of[14C]oleic acid into the cuticle of growing internodes. GA also caused a qualitative change in the incorporation pattern of palmitic acid into several cutin monomers, the most prominent of which was tentatively identified by thin-layer chromatography as a derivative of dihydroxyhexadecanoic acid. Rapidly growing plant organs exhibit longitudinal tissue stress: the epidermal cell layer is under tension with a tendency to contract, whereas the internal cells are under compression with a tendency to expand. As a result of tissue stress, longitudinally sliced sections of elongating internodes bend outward upon isolation from the plant. Treating rapidly growing rice internodes with cutinase reduced such outward bending, indicating that the cuticle contributes to tissue stress. Based on these results, we propose that rapidly elongating structures such as deepwater rice internodes constitute an excellent system to study cuticle formation at the biochemical and cellular level