Pre- and post-storage applications of rhamnolipids and cyprodinil + fludioxonil against <i>Aspergillus</i> section <i>Nigri</i> population and ochratoxin A contamination of grapes

Grapevines constitute a very important crop in Greece and ochratoxin A (OTA) contamination of grapes is one of the most serious problems. The main aim of this study was to investigate the fungicidal activity of the fungicide Switch 62.5WG (37.5% v/v cyprodinil + 25% v/v fludioxonil) and Rhapynal (80% rhamnolipids) to reduce the black <i>Aspergillus</i> spp. (section <i>Nigri</i>) population and OTA contamination of grapes grown in Greece. Applications with the above products were conducted both at the harvesting stage and after cold storage. The results showed that pre-harvest applications with Switch 62.5WG or Switch 62.5WG + Rhapynal generally reduced the black <i>Aspergillus</i> spp. population, but not the OTA contamination of grapes. However, a repeated application after cold storage further reduced the black <i>Aspergillus</i> spp. population and significantly reduced the OTA contamination of grapes. Generally, this study showed that it is possible to reduce the black <i>Aspergillus</i> spp. population, but not the ochratoxin A contamination of grapes by spray applications with the fungicide Switch 62.5WG. However, fungicide application to grapes immediately after cold storage (2 months) could reduce ochratoxin A contamination of grapes and further reduce the black <i>Aspergillus</i> spp. population.