Determination of hesperidin and limonin levels as part of the defense mechanism of some lemon varieties (Citrus lemon (L.) Burm f.) against mal secco disease (Phoma tracheiphila (Petri) Kanc.et Ghik.)

In this study, it was aimed to detect incidence of Mal secco disease which caused by Phoma tracheiphila based on phenolic compounds content especially hesperidin and limonin. Among the detected 6 lemon varieties (Meyer, Kütdiken, Enterdonato, Yediveren, Sweet lemon and Euroka) disease caused by Phoma tracheiphila was inoculated artifically, before and after inoculation samples were taken from the leaves, branches and stem of the lemon varieties and hesperidin and limonin are detected identificaly and quantifical using HPLC (High Pressure Liquid Chromotography) technique. The hesperidin and limonin concentration was increased among the experimental samples. According to the calculated values based on the percentages of incensement either hesperidin or limonin or both of them was found to be higher in tolerant and middle tolerant varieties (Sweet lemon, Meyer and Enterdonato). In addition various levels of limonin and hesperidin (1,5,10,25,50,75,100 ppm) too the effects on P. tracheiphila incidence or inhibit percentages were detected in vitro conditions. As a result, the opposite reelection was found to be between phenolic compounds quantity and disease development. Limonin was found to be more effective than the hesperidin in term of the disease incidence in artificial experiment.