CAMBIOS DIARIOS DEL CONTENIDO DE PIGMENTOS FOTOSINTÉTICOS EN HOJAS DE CALÉNDULA BAJO SOL Y SOMBRA

Abstract

Calendula (Calendula officinalis L.) is an essential medicinal plant in unconventional medicine from homeopathy to oriental medicine. Marketing of marigold lies in second place in Colombia, among the plants used for phytopharmacy of medicinal species. A study was carried out in Tunja, Colombia, aimed to evaluate, hourly, the chlorophylls and carotenes content in marigold plants grown at full sun exposure or under a 37% shade cloth. The pigments extraction was carried out by diluting in methanol and its concentration was determined by a spectrophotometric method. Results showed differences of the contents of chlorophyll b, carotenes and total chlorophyll throughout the day with trend to increase between 6:00 and 18:00 hours. Shade affected the chlorophyll a / chlorophyll b ratio and carotenes / chlorophyll ratio. While the value of the chlorophyll a / chlorophyll b ratio was higher in leaves of shaded plants, the value carotenes / chlorophyll ratio was higher in plants grown under full sun exposure. Daily changes in pigment content have been controversial over the results of many studies, however, it should be taken into account that pigments content varies with age of leaves and among species.

Keywords

• Calendula officinalis
• stress
• chlorophyll
• carotene.