Evaluación de extractos vegetales para manejo de hongos patógenos en banano y fresa almacenados

Abstract

En la Universidad Nacional de Colombia -Sede Palmira, se obtuvieron extractos etanólicos (1.000 ml), macerados (100 g) de llantén (Plantago major L), ruda (Ruta graveolens L), pronto alivio [Lippia alba (Mill) NE BROS] y helecho marranero [Pteridium aquilinum (Kaulf) Maxon]. Para la evaluación del control de C. musae y B. cinerea se utilizaron dieciséis tratamientos (cuatro extractos de plantas, dos medios de extracción, dos diluciones y tres repeticiones).Se adicionaron tres testigos: absoluto (PDA); solvente (PDA + etanol o agua); y químico (PDA + fungicida químico). Las diluciones se realizaron con el solvente de obtención del extracto. La evaluación in vivo se realizó con extractos etanólicos diluidos al 25%. El solvente etanólico disminuyó el desarrollo de los hongos en 68%. Los frutos donde se aplicó el extracto de ruda y pronto alivio presentaron mayor incidencia y grado de severidad. Palabras claves: Plantago major; Ruta graveolens; Lippia alba; Pteridium aquilinum; Colletotrichum musae; Botrytis cinérea; Manejo poscosecha.

This study was carried out get knowledge about fungicidal properties of vegetable extracts to the control of the pathogenyc fungi (Colletotrichum musae and Botrytis cinerea) in banana (Musa sapientum) and strawberry (Fragaria sp) during the pos harvest storage, at the National University of Colombia headquarters in Palmira. Ethanolics extracts of the following vegetable species were evaluated: Plantago major L, Ruta graveolens L, Lippia alba (Mill) NE BROS), Pteridium aquilinum (Kaulf) Maxon. The extracts were obtained by the percolation method starting from the macerated material (100 g) and 1000 ml of solvent. The fungi was isolated from the strawberry (Fragaria sp) affected by B. cinerea and banana Gross mitchel affected by C. musae. To evaluate the control of the fungi C. musae and B. cinerea sixteen treatments were used (four extracts of plants, two extraction media, two dilutions and three repetitions). Three control treatments were added: absolute (PDA); solvent (PDA + ethanol or water); and chemical (PDA + chemical fungicide). The dilutions were prepared with the solvent used to obtain the extract. The evaluation in vitro was maid with ethanolics extracts diluted at 25%, because these presented the best results in the previous tests. The results indicate that the ethanolic solvent decreased the development of the fungi in 68%. The fruits in which the etanolic extract of ruda and pronto alivio was applied presented bigger incidence and grade of severity. Keys words: Vegetable extract; patogenic fungi; Colletotrichum musae; Botrytis cinérea; post harvest