title: Effect of crude plant extracts from some Oaxacan flora on two deleterious fungal phytopathogens and extract compatibility with a biofertilizer strain.
abstract: The antimicrobial activity of 12 plant extracts was tested against the phytopathogens Alternaria alternata and Fusarium solani. In addition, the compatibility of the extracts toward Bacillus liqueniformis, a biofertilizer and a non-target microorganism, was assessed. Plants tested belong to the Euphorbiaceae, Asteraceae, Crassulaceae, Rubiaceae, Convolvulaceae, Verbenaceae, Orchidaceae, Nyctaginaceae, Boraginaceae, and Tiliaceae families and were collected in the State of Oaxaca. The antifungal activity of the plant extracts (50-100 mg/mL) against A. alternata and F. solani, was determined by measuring the mycelium radial growth and obtaining the minimum inhibitory concentration (MIC) of fungal growth. In addition, with the aim of finding plant extracts which are compatible with a B. licheniformis biofertilizer strain and to test the non-toxic nature of the treatments, the toxicity of the extracts toward this strain was evaluated using the agar diffusion method. Azoxystrobin (12 μg) and chloramphenicol (30 μg) were used as positive controls for the pathogens and for the non-target bacteria, respectively. Plant extracts inhibited fungal growth in the ranges of 0.76-56.17% against F. solani and 2.02-69.07% against A. alternata. The extracts of Acalypha subviscida, Ipomoea murucoides, Tournefortia densiflora and Lantana achyranthifolia showed MIC values between 5.77-12.5 mg/mL for at least one of the fungal species. The best treatment, Adenophyllum aurantium, exhibited a maximum inhibition for both F. solani (56.17%, MIC = 7.78 mg/mL) and A. alternata (68.64% MIC = 7.78 mg/mL), and resulted innocuous toward B. licheniformis. Therefore, this plant has an outstanding potential for the agroecological control of fungal phytopathogens in industrial crops.
authors.affiliation: Instituto de Recursos, Universidad del Mar Puerto Ángel, México.
authors.forename: Karla I
authors.initials: KI
authors.lastname: Lira-De León
authors.affiliation: Instituto de Recursos, Universidad del Mar Puerto Ángel, México.
authors.forename: Marco V
authors.initials: MV
authors.lastname: Ramírez-Mares
authors.affiliation: Instituto de Biotecnología, Universidad del Papaloapan Tuxtepec, México.
authors.forename: Vladimir
authors.initials: V
authors.lastname: Sánchez-López
authors.affiliation: Unidad de Investigación y Desarrollo en Alimentos, Instituto Tecnológico de Veracruz Veracruz, México.
authors.forename: Mario
authors.initials: M
authors.lastname: Ramírez-Lepe
authors.affiliation: Instituto de Agroindustrias, Universidad Tecnológica de la Mixteca Huajuapan de León, México.
authors.forename: Raúl
authors.initials: R
authors.lastname: Salas-Coronado
authors.affiliation: Instituto de Agroindustrias, Universidad Tecnológica de la Mixteca Huajuapan de León, México.
authors.forename: Norma F
authors.initials: NF
authors.lastname: Santos-Sánchez
authors.affiliation: Instituto de Agroindustrias, Universidad Tecnológica de la Mixteca Huajuapan de León, México.
authors.forename: Rogelio
authors.initials: R
authors.lastname: Valadez-Blanco
authors.affiliation: Instituto de Agroindustrias, Universidad Tecnológica de la Mixteca Huajuapan de León, México.
authors.forename: Beatriz
authors.initials: B
authors.lastname: Hernández-Carlos
keywords: Adenophyllum aurantium; Alloispermum integrifolium; Ipomoea murucoides; Lantana achyranthifolia; Tournefortia densiflora; antifungal activity; filamentous fungi; plant extracts