The use of colored screens represents a new agricultural concept, which combines the plant physical protection with the solar radiation selective filtration to obtain expected light-regulated physiological responses. The aim of this work was to verify the effect of shading using colored screens on biometric, anatomical and physiological characteristics of Artemisia vulgaris. Plants were grown in pots kept in a completely randomized distribution, and treatments consisted of red and blue Cromatinet-type (50%) screens, besides full sun (without screen). The studied variables were more affected by light intensity than by light spectral quality. Stem diameter and starch grain number were not influenced by treatments, whereas height, root:shoot ratio, leaf thickness, and chlorophyll and carotenoid content were influenced by light intensity. Leaf area, plant dry matter and chloroplast number were affected by both light intensity and spectral quality.
Artemisia vulgaris; medicinal plants; light intensity; light quality
