title: Influence of blue light on the leaf morphoanatomy of in vitro Kalanchoe pinnata (Lamarck) Persoon (Crassulaceae).
abstract: Kalanchoe pinnata (Lamarck) Persoon (Crassulaceae) (air plant, miracle leaf) is popularly used to treat gastrointestinal disorders and wounds. Recently, the species was tested to treat cutaneous leishmaniasis with successful results. This medicinal activity was associated with the phenolic fraction of the plant. Blue light induces biosynthesis of phenolic compounds and many changes in anatomical characteristics. We studied the effects of supplementary blue light on the leaf morphology of in vitro K. pinnata. Plants cultured under white light (W plants) only and white light plus blue light (WB plants) show petioles with plain-convex section, amphistomatic leaf blades with simple epidermis, homogeneous mesophyll with densely packed cells, and a single collateral vascular bundle in the midrib. W plants have longer branches, a larger number of nodes per branch, and smaller leaves, whereas WB plant leaves have a thicker upper epidermis and mesophyll. Leaf fresh weight and leaf dry weight were similar in both treatments. Phenolic idioblasts were observed in the plants supplemented with blue light, suggesting that blue light plays an important role in the biosynthesis of phenolic compounds in K. pinnata.
authors.affiliation: Departamento de Botânica, Universidade Federal do Rio de Janeiro, Centro de Ciências da Saúde, Instituto de Biologia, Cidade Universitária, 21.941-902 Rio de Janeiro, Brazil. mlealcosta@gmail.com
authors.forename: Marcos Vinicius
authors.initials: MV
authors.lastname: Leal-Costa
authors.forename: Luana Beatriz dos Santos
authors.initials: LB
authors.lastname: Nascimento
authors.forename: Nattacha dos Santos
authors.initials: Ndos S
authors.lastname: Moreira
authors.forename: Fernanda
authors.initials: F
authors.lastname: Reinert
authors.forename: Sônia Soares
authors.initials: SS
authors.lastname: Costa
authors.forename: Celso Luiz Salgueiro
authors.initials: CL
authors.lastname: Lage
authors.forename: Eliana Schwartz
authors.initials: ES
authors.lastname: Tavares
mesh_terms: D031962:Kalanchoe / Q000033:anatomy & histology / Q000166:cytology / Q000378:metabolism / Q000528:radiation effects*; D008027:Light; D010636:Phenols / Q000378:metabolism; D018515:Plant Leaves / Q000033:anatomy & histology / Q000166:cytology / Q000378:metabolism / Q000528:radiation effects*
chemical_list: D010636:Phenols