Influência da radiação solar no desenvolvimento vegetativo e reprodutivo de Acmella oleracea em sistema semi-hidropônico sob cultivo protegido

Abstract

The jambu Acmella oleracea is a Non-Conventional Food Plant (PANC) of major relevance in the Amazonian bioeconomy, especially due to the use of its flower buttons by the pharmaceutical, cosmetic and gastronomic industries.[3][4] This study evaluated the influence of solar radiation patterns on the growth, flowering and biomass production of jambu grown in a semi-hydroponic system under protected cultivation in Manaus, integrating environmental data obtained by remote sensing. The experiment was carried out in a greenhouse oriented in the North–South direction, with five benches and 6 plants per bench, totaling 30 plants grown in an inert substrate and fertigated by drip irrigation; maps of diffuse shortwave irradiance at the surface, total solar irradiance and photosynthetically active radiation (PAR) were generated using data from the NASA POWER project and analyzed in QGIS and 3D Sun-Path. The resultsindicated a progressive increase in PAR and total solar irradiance in October along the historical time series and showed that benches more exposed to radiation exhibited greater plant height, number of leaves, fresh and dry mass, and higher production of flower buttons. Internal differences in shading explained the variability among benches and made it possible to identify radiation ranges that were more favorable to vegetative vigor and floral yield. The fresh yield obtained under protected cultivation, 11,480 g m⁻², exceeded reference values for conventional open-field cultivation, which range from 300 to 500 g m⁻², highlighting the productive potential of the semi-hydroponic system when light is properly managed. It is concluded that the North–South orientation of the greenhouse, combined with the integrated use of NASA POWER data and geotechnologies, is effective for characterizing and optimizing the light environment, resulting in better agronomic performance of Acmella oleracea. Production in the semi hydroponic system proved to be viable for obtaining flower buttons in quantities and weights compatible with the requirements of the pharmaceutical market, reinforcing the crop’s potential in high value-added production chains in the Amazon.