Phenolic compound levels in bulb skins of garlic varieties with normal and abnormal colour

lt was observed that bulb skins that presented red colour, abnormal in some garlic (Allium sativum L.) varieties, depreciate the product and show poor sprouting. This abnormal skin colour has been associated with Sclerotium rolfsii Sacc. incidence. lt is known that many plant species react to pathogen attacks through a biochemical defense process, increasing the phenolic compound concentrations. These are substances toxic or inhibitory to pathogen growth. An analysis was made of phenolic compounds of garlic varieties with normal and abnormal colour caused by the incidence of Sclerotium. lt was observed that phenolic compound levels were significantly higher in varieties with abnormal colour. The results suggest a relationship between the abnormal rosy colour of bulb skins and higher levels of phenolic compounds, induced by Sclerotium rolfsii incidence.