title: A non-destructive method for testing two components of the behaviour of soil-applied agricultural chemicals over a long period.
abstract: BACKGROUND
  Owing to the complexity of soil composition, accurate predictions of both apoplastic systemicity of lipophilic xenobiotics and their leaching from the soil are made difficult. Therefore, a non-destructive method to assess directly these two components of the spatial behaviour of soil-applied phytochemicals is needed.
  
  
  RESULTS
  The plant selected was a dwarf tomato, which can exude an abundant apoplastic fluid through large stomata for several months. The feasibility and reliability of the method were assayed using three triazoles exhibiting different log D values. HPLC-MS analyses indicated that triadimenol (log D = 2.97) was clearly the most mobile compound within the apoplast, especially its diastereoisomer A. Propiconazole (log D = 3.65) and penconazole (log D = 4.64) exhibited a similar low systemicity. The data remained the same when the three fungicides were applied together on the soil. Long time-course studies (1.5 months) of penconazole behaviour indicated that, in contrast to leaching, which decrease sharply, root-to-shoot translocation remained almost unchanged during the whole experiment, in spite of the high lipophilicity of this fungicide.
  
  
  CONCLUSIONS
  This method must contribute to a better knowledge of the behaviour of commercial soil-applied phytochemicals. It can also be used to screen new xenobiotics within strategies to satisfy environmental requirements.
authors.affiliation: Laboratoire Synthèse et Réactivité des Substances Naturelles, Unité Mixte de Recherche CNRS 6514, Université de Poitiers, Poitiers, France.
authors.forename: Marie-Anne
authors.initials: MA
authors.lastname: Guglielmi
authors.forename: Françoise
authors.initials: F
authors.lastname: Rocher
authors.forename: Sandrine
authors.initials: S
authors.lastname: Legros
authors.forename: Jean-Louis
authors.initials: JL
authors.lastname: Bonnemain
authors.forename: Jean-François
authors.initials: JF
authors.lastname: Chollet
mesh_terms: D016573:Agrochemicals / Q000737:chemistry* / Q000378:metabolism*; D001681:Biological Assay / Q000379:methods*; D005659:Fungicides, Industrial / Q000737:chemistry / Q000378:metabolism; D057927:Hydrophobic and Hydrophilic Interactions; D018551:Solanum lycopersicum / Q000166:cytology / Q000378:metabolism; D018517:Plant Roots / Q000166:cytology / Q000378:metabolism; D054046:Plant Stomata / Q000166:cytology / Q000378:metabolism; D012987:Soil / Q000737:chemistry*; D013997:Time Factors; D014230:Triazoles / Q000737:chemistry / Q000378:metabolism; D015262:Xenobiotics / Q000737:chemistry / Q000378:metabolism
chemical_list: D016573:Agrochemicals; D005659:Fungicides, Industrial; D012987:Soil; D014230:Triazoles; D015262:Xenobiotics; C087058:penconazole