title: Plant extracts to control Alternaria alternata in Murcott tangor fruits.
abstract: BACKGROUND
  Alternaria alternata causes the Alternaria brown spot disease (ABS) in many tangerines and their hybrids worldwide. Plant extracts offer an alternative method for controlling this disease, which control is based on chemical fungicides.
  
  
  OBJECTIVE
  To identify plant species with antifungal properties against A. alternata, the causal agent of the ABS.
  
  
  METHODS
  Plant extracts prepared from leaves, barks, flowers, and stalks collected from 105 plant species in the State of Minas Gerais, Brazil, were tested for activity against the fungus A. alternata in vitro and in vivo.
  
  
  RESULTS
  The most promising extract was obtained from Anadenanthera colubrina, which reduced the disease on Murcott tangor fruits to levels obtained with commercial fungicides. Artemisia annua, Cariniana estrelensis, Ficus carica, and Ruta graveolens presented moderate in vitro antifungal activity, but no effects were observed on the disease when the extracts were applied to fruits inoculated with the fungus. Besides, A. colubrina was the most active extract against A. alternata in the in vitro assay.
  
  
  CONCLUSIONS
  The results obtained in the in vitro and in vivo assays suggested that the fungal growth test, which uses 96-well polypropylene plates, seems to be appropriate for selecting potential plant species for testing new methods to control ABS.
authors.affiliation: Departamento de Fitopatologia, Universidade Federal de Lavras, Minas Gerais, Brazil.
authors.forename: Daniel Diego Costa
authors.initials: DD
authors.lastname: Carvalho
authors.forename: Eduardo
authors.initials: E
authors.lastname: Alves
authors.forename: Renato
authors.initials: R
authors.lastname: Barbosa Camargos
authors.forename: Denilson
authors.initials: D
authors.lastname: Ferreira Oliveira
authors.forename: José Roberto
authors.initials: JR
authors.lastname: Soares Scolforo
authors.forename: Douglas Antônio
authors.initials: DA
authors.lastname: de Carvalho
authors.forename: Tereza Raquel
authors.initials: TR
authors.lastname: Sâmia Batista
mesh_terms: D000528:Alternaria / Q000187:drug effects* / Q000254:growth & development* / Q000648:ultrastructure; D002957:Citrus / Q000382:microbiology*; D008855:Microscopy, Electron, Scanning; D010935:Plant Diseases / Q000517:prevention & control*; D010936:Plant Extracts / Q000494:pharmacology* / Q000627:therapeutic use*
chemical_list: D010936:Plant Extracts