“Ermioni” a new Lemon Cultivar Resistant to Mal secco Disease (Phoma tracheiphila)

A lemon tree resistant to citrus tracheomycotic disease Mal secco ( Phoma tracheiphila ) found in a Greek orchard and its progenies were evaluated. Scions budded on sour orange and Volkameriana rootstocks or cuttings rooted in mist were placed under natural infections or inoculated artificially with Mal secco inoculum. No disease symptoms appeared on the original tree, while in bud‐progenies only 16 out of approximately 2500 field grown trees were diseased by Mal secco. In 45 artificially inoculated trees only two were infected by the fungus. Analysis of leaf proteins using electrophoresis and further genetic control of gene/enzyme 6‐Phosphogluconate dehydrogenase (6‐PGD) system were carried out for the resistant selection: the Greek varieties Maglini, Adamopoulou, Karystini and the Italian Monachello and Interdonato. Protein analysis showed a close relationship of the resistant selection with var. Maglini, of which a scion is the resistant selection, while the isozyme genetic marker showed three different electrophoretic patterns, the resistant selection being in a separate pattern. Some phenotypical differences between the resistant selection and Maglini were also observed. The phenotypical differences, the resistance to Mal secco, the differences in proteins from all other varieties except Maglini and the different electrophoretic pattern of 6‐PGD of this selections vs other varieties, suggest a new cultivar, for which the name “Ermioni” is proposed.