Utilização de carvão ativado para libertação controlada de rincoforol

Abstract

Red ring disease is considered one of the main diseases causing damage to fruit production and plant mortality. In Brazil, this disease also occurs in several native palm trees (Arecáceas). Furthermore, tropical conditions favor the high population of the main vector insect (Rhynchophorus palmarum) of the disease-causing nematode (Bursaphelenchus cocophilus). In recent years, an increase in the population of R. palmarum and, consequently, in the number of plants attacked by the red ring in commercial plantations has been reported. Currently, most control strategies for phytophagous arthropods in agricultural crops use pesticides. However, great advances are related to the use of semiochemicals. One of the obstacles in the process of using semiochemicals is in the stage of their release to the environment. Due to environmental conditions, the volatilization kinetics of this substance can be harmed, causing excessive release rates causing high costs in the application process, or very low, to the point of not being identified by insects. The present work aims to determine a device for the prolonged release of the aggregation pheromone rhinchophorol, from adsorption and desorption on activated charcoal. Polyethylene sachets approximately 6.0 cm long and 4.0 cm high were used. In order to have greater release of the studied pheromone, holes were made in the sachets 0.5 cm apart, with 5 and 15 perforations. Having as variables the activated carbon granulometry, presence/absence of stabilizer and the number of holes in the sachet. For this purpose, in this work, a 2³ full factorial design was carried out, where the factors evaluated were: number of holes in the sachet, granulometry of activated charcoal from bovine bone and the influence of the use of stabilizer with the pheromone. As an answer, mass loss was used. It was found that the best condition found, when compared with the release performed by eppendorf, was: the use of rhinchophorol with the presence of stabilizer, adsorbed on charcoal with smaller granulometry (35 < ᴓ < 28 mesh) and sachet with 5 holes, condition found in experiment number 3, which showed a lower mass loss.