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Notes:
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A study was undertaken to evaluate the impact of the application of several fungicide treatments used in Spanish vines on
Aspergillus carbonarius
growth and ochratoxin A production. Three trials were designed in order: (1) to screen 26 fungicides
at the doses recommended by manufacturers on grape-like synthetic medium at 20 and 30
C; (2) to find out the minimum
inhibitory concentration of each fungicide for
A. carbonarius
growth on synthetic medium; and (3) to investigate the effect
of several fungicides on
A. carbonariu
s-inoculated grapes. In synthetic medium nine fungicides significantly reduced
A. carbonarius
growth rate. Meanwhile, 13 fungicides completely inhibited its growth. In general, growth was faster at 30
C
than at 20
C, contrary to ochratoxin A production. Fungicides that stopped fungal growth also inhibited ochratoxin A
production, but not all the fungicides that reduced growth reduced the ochratoxin A synthesis. In general, fungicides that
contained copper or strobilurins reduced both growth and ochratoxin A production, contrary to sulphur fungicides. At the
optimum temperature for
A. carbonarius
growth of 30
C, higher amounts of fungicide were needed to prevent fungal growth
than at 20
C. Among the fungicides that inhibited
A. carbonarius
growth on synthetic medium at the initial doses, cyprodinil
seemed to be the active ingredient more effective at stopping fungal growth when testing reduced doses. The fungicide effect
on grapes was similar to that on synthetic medium. Both infection and ochratoxin A production were reduced when using
cyprodinil (37.5%) plus fludioxonil (25%) and azoxystrobin (25%). Penconazole (10%) also showed a clear reduction
in ochratoxin A production at both temperatures, although infection was only reduced at 20
C. Ochratoxin A reduction was
strain and temperature-dependent. In general, fenhexamid (50%), mancozeb (80%) and copper hydroxide (80%) plus
copper (50%) enhanced infection and ochratoxin A production.
The work was funded by the Catalonian Government (Direcció General de Recerca, Generalitat de Catalunya), the Spanish Government (CICYT, Comisión Interministerial de Ciencia y Tecnologí, AGL2004-07549-C05-01, and Ramon y Cajal programme) and the European Commission, Quality of Life Programme (QoL), Key Action 1 (KA1) on Food, Nutrition and Health (QLRT- 2000-01761). The authors are grateful to Syngenta- Agro S.A. (Spain) and Le ́ rida Unio ́ n Quı ́ mica S.A. (Luqsa, Spain) for providing the fungicides used |
