Extratos vegetais no controle da antracnose em cebolinha

Abstract

The chives, is a vegetable well known and used by the Brazilian population. During their cultivation, plants are exposed to diseases caused by fungi and bacteria. Among the diseases of fungal origin, the anthracnose, caused by phytopathogen of the genus Colletotrichum, of easy dissemination and surviving parasitizing vegetables stands out. The objective of this work was to evaluate the extracts obtained from the plants Picrolema sprucei, Piper marginatum, Croton cajucara, Curcuma longa and Laportea aestuans, in the control of anthracnose of chives. The experiment was carried out in the Laboratory of Microbiology and Phytopathology and in a greenhouse of the Faculty of Agrarian Sciences, Federal University of Amazonas, where morphological characterization and molecular identification of Colletotrichum sp. associated with anthracnose of chives; Obtaining and Evaluating (EBA) Aqueous Crude Extracts; obtaining and evaluating the hexane, acetate-ethylic and methanolic fractions of plant extracts; evaluation of the effect of fractionated extracts on mycelial growth (ICM) and Esporulation Inhibition Percentage (PIE). The data were submitted to analysis of variance (ANOVA), when the significance was verified, through the F test, the means were compared by the Tukey test at the 5% probability level. In the in vitro test with crude aqueous extract (EBA), the lowest ICM value was obtained with the treatments Piper marginatum and Picrolema sprucei. As for PIE, the highest value was obtained at a concentration of 50%, and the EBA of Croton cajucara presented greater inhibition of sporulation of the phytopathogen. As for the in vitro assay with fractionated extracts, the lowest ICM value was obtained with the acetylic fraction of Curcuma longa. As for PIE, the highest value was obtained with the methanolic fraction of Picrolema sprucei. In the in vivo assay, the extracts of P. marginatum and Picrolema sprucei showed better performance in controlling the severity of the disease.