S25 - Session P1 - Photoselective screens in biomass production and essential oil yield in basil cultivars

Authors: Jose Magno Luz *, Mirian Nomura, Arie Blank, Carlos Ribeiro Rodrigues, Sérgio Macedo Silva, Roberta Camargo Oliveira, Mércia Freitas Alves, Daniela Apareci Nizio

The photoselective screens, by modulating the light, can increase the production of biomass and essential oil of basil. The objective of this work was to evaluate the effect of photoselective screens on biomass production and composition of essential oil yield of basil cultivars, grown in two growing seasons, spring/summer and autumn/winter. The experimental design was in randomized blocks, in a split-plot scheme, testing, in the plots, five cultivation environments (three meshes in pearl, blue and red, all with 20% shading, and black screen with 30% shading, and a growing environment in full sun) and, in the subplots, four cultivars of basil (Anise, Cinnamon, Italian Large Leaf and Maria Bonita). The cultivation of basil under photoselective screens increased the height of plants. The use of a blue screen in spring/summer cultivation provided greater fresh biomass of the aerial part for the cultivars Anise and Maria Bonita, pearl for Cinnamon, and red for Italian Large Leaf. The use of screens did not promote an increase in the productivity of essential oil. The spring/summer growing season provided plants with greater height, greater production of fresh leaf biomass, and a higher yield of essential oil, in addition to greater biosynthesis of the main constituents of essential oil of all the cultivars analyzed. Although the cultivars have different responses regarding the content of the chemical constituents of the essential oil depending on the planting season, it appears that the spring/summer season favored the highest production of the main constituents of each cultivar: methyl chavicol for Anise, methyl cinnamate for Cinnamon, linalool and eugenol for Italian Large Leaf and linalool for Maria Bonita.