Effect of plant extracts for the control on plant pathogenic bacteria.
Guevara Y., Maselli A., Sánchez M. del C.
Author Affiliation: Departamento de Protección Vegetal, FONAIAP-CENIAP, Apdo. 4653, Maracay 2101-A, Edo, Aragua, Venezuela.
Manejo Integrado de Plagas : 38-44
Abstract : The bactericidal effect of several plant extracts was evaluated against plant pathogenic bacteria from mango (Mangifera indica), sunflower (Helianthus annuus), papaya (Carica papaya) and banana (Musa sp.) in laboratory tests. The tests were performed with sterilized filter paper discs and three drying times (moist, dried for 24 hours and dried for 48 hours). Six discs were then placed, each one impregnated with a different plant extract, on Petri dishes where pure bacteria cultures were growing. The 17 species evaluated belong to the families: Acanthaceae, Apocynaceae, Boraginaceae, Cucurbitaceae, Euphorbiaceae, Lauraceae, Meliaceae, Myrtaceae, Sapindaceae, Sapotaceae and Umbelliferae, and two undetermined families. Extracts were prepared in four ways: fresh material liquidised with distilled water in a 1:3 w/v proportion; infusion of fresh plant material in a 1:6 w/v proportion; infusion of fresh plant material in a 1:3 w/v proportion and infusion of dried plant material in a 1:6 w/v proportion. After 48 hours, the greatest bactericidal effects in vitro, for control of the Erwinia genus were found with coriander (Eryngium foetidum), yuquilla (Ruellia tuberosa) and cundeamor (Momordica charantia). The extract of mamón (Melicocca bijuga) had bactericidal effects against Pseudomonas sp. on banana.