Qualidade de luz na biometria e anatomia foliar de plântulas de Cattleya loddigesii L. (Orchidaceae) micropropagadas

Abstract

The light quality is responsible for the morphogenesis in plants. It is mediated by a series of processes involving light receptors, mainly in the red blue region. The aim of this research was to observe the anatomical leaf alterations as well as the biometric characteristics of in vitro cultured Cattleya loddigesii ‘Tipo’. Two different colour shading nets (red and blue, 50% mesh) were tested and compared with a control without the shading nets in greenhouse and growth room. Plantlets of 1.0cm in length with roots produced by self pollinization and by seeds in vitro germination were inoculated in WPM medium and submitted to these different incubation environments. After 180 days of inoculation the plantlets were evaluated. It was observed that the culture environment promote anatomical and biometric alterations in Cattleya loddigesii ‘Tipo’ plantlets micropropagated. The changes promoted by the cultivation in natural light show greater photosynthetic capacity, through greater differentiation of the chlorenchyma tissue, promoting a leaf surface anatomically adapted to the acclimatization stage.