Change in leaf anatomy, physiology, and essential oil of Varronia curassavicaJacq. accessions under two light conditions / Cambio en la anatomía de la hoja, fisiología y aceite esencial de accesiones de Varronia curassavica Jacq. bajo dos condiciones de luz

The aim of this study was to evaluate the effect of light on anatomy, physiology and essential oil content and composition of Varronia curassavica. They were analysed two light conditions (full sunlight and protected environment with 50% shade screen) and five accessions (VCUR-101, VCUR-102, VCUR-201, VCUR-302, VCUR-802). V. curassavica cultivated in full sun presented a greater development of the leaf blade and palisade parenchyma thickness for all accessions. Chlorophyll levels did not differ according to the two light environments. The leaf area was larger in the protected environment. The essential oil yield of the accessions ranged from 0.26 to 0.87 mL/plant in full sun and from 0.34 to 0.53 mL/plant in the protected environment. The composition of the essential oil was influenced by the light and the accession. All accessions presented (E)-caryophyllene and α-humulene. The influence of light on the evaluated variables is genotype dependent.

El objetivo de este estudio fue evaluar el efecto de la luz sobre la anatomía, fisiología, el contenido y composición de aceites esenciales de Varronia curassavica. Se analizaron dos condiciones de luz (pleno sol y ambiente protegido con 50% de pantalla de sombra) y cinco accesiones (VCUR-101, VCUR-102, VCUR-201, VCUR-302, VCUR-802). V. curassavica cultivada a pleno sol presentó mayor desarrollo del limbo foliar y espesor del parénquima en empalizada para todas las accesiones. Los niveles de clorofila no difirieron según los dos entornos de luz. El área foliar fue mayor en el ambiente protegido. El rendimiento de aceite esencial de las accesiones varió de 0,26 a 0,87 mL/planta a pleno sol y de 0,34 a0,53 mL/planta en el ambiente protegido. La composición del aceite esencial fue influenciada por la luz y la accesión. Todas las accesiones presentaron (E)-cariofileno y α-humuleno. La influencia de la luz sobre las variables evaluadas depende del genotipo.

In vitro conservation and leaf anatomy of different chemotypes of Lippia alba (Mill.) N. E. BR / Conservação in vitro e anatomia foliar de diferentes quimiotipios de Lippia alba (Mill.) N. E. BR

The aim of this work was to develop an in vitro conservation protocol for Lippia alba that involved mineral oil and to study the leaf anatomy of L. alba genotypes in in vitro and ex vitro environments. In vitro conservation involved five genotypes; LA-13 and LA-57 (carvone chemotype); LA-22 (linalool chemotype); and LA-29 and LA-44 (citral chemotype). Each genotype was treated with mineral oil, with water, and a control at 18°C and 23°C. Survival (%), shoot height (cm) and leaf color were assessed at 180 and 270 days. The genotypes with the best in vitro conservation outcomes (LA-13 and LA-57) were used to study the anatomy of the leaves. Midrib thickness, leaf blade thickness, adaxial and abaxial cuticles and the number of glandular and tector trichomes were assessed. A temperature of 18°C was optimal for the conservation of genotypes of the carvone chemotypes. The explants were short and had green leaves. This was especially true for LA-57, whose height did not exceed 2.0 cm. At 270 days, the LA-13 and LA-57 genotypes continued to have green and viable leaves, especially LA-57, which had the lowest mean height. Field plants of the carvone chemotype had thicker midribs, leaf blades, and cuticles and had more trichomes. The LA-57 genotype had the most glandular and tector trichomes.

O objetivo deste estudo foi desenvolver um protocolo de conservação in vitro com óleo mineral e estudar a anatomia foliar de genótipos de L. alba nos ambientes in vitro e ex vitro. A conservação in vitro constou de cinco genótipos LA-13 e LA-57 (quimiotipo carvona); LA-22 (quimiotipo linalol); LA-29 e LA-44 (quimiotipo citral), três tratamentos (com óleo mineral, com água e controle) e duas temperaturas 18 e 23°C. Aos 180 e 270 dias, avaliou-se a sobrevivência (%), altura da parte aérea (cm) e coloração das folhas. Os genótipos com os melhores resultados da conservação in vitro (LA-13 e LA-57) foram utilizados para estudos de anatomia. Avaliou-se espessura da nervura central, espessura do limbo foliar, cutículas adaxial e abaxial e quantidade de tricomas glandulares e tectores. A temperatura a 18°C foi a ideal para a conservação dos genótipos do quimiotipo carvona, com folhas verdes e baixos valores para altura, destacando-se LA-57 cuja altura não ultrapassou 2,0 cm. Aos 270 dias LA-13 e LA-57 permaneceram com folhas verdes e viáveis, com destaque para LA-57 com menores médias de altura. A anatomia do quimiotipo carvona mostrou que as plantas de campo apresentaram maiores espessuras da nervura, limbo e cutículas, e maiores quantidades de tricomas. O genótipo LA-57 obteve a maior quantidade de tricomas glandulares e tectores.