Puccinia porri (previously known as Puccinia allii) is one of the most important rust fungi that cause rust disease on garlic, onions, leek and chives. It usually appears as bright orange spots on infected plants. Typical symptoms of the rust disease on Egyptian leek were observed in Nubaria, El-Behera, Egypt, in March and April 2021. This is the first report on observing symptoms of rust disease caused by P. porri on Egyptian leek in Egypt. The aim of this research was to investigate antifungal properties of bergamot (Citrus bergamia L.) essential oil against Puccinia porri in vitro and under greenhouse experiments. The impact of various bergamot oil concentrations (100, 250, 500, 750 and 1000 µl/L) on the germination of urediniospores of the causing fungus was investigated in laboratory conditions. The results showed that bergamot oil reduced the percentage of urediniospores germination at all concentrations …