Postharvest control alternatives for the management of the moth Ectomyelois ceratoniae Zeller (Pyralidae) in Tunisia: Essential oil fumigation and its impacts on date quality

Abstract: The carob moth Ectomyelois ceratoniae Zeller is the most important and destructive insect pest attacking dates both in field and during storage in Tunisia. It caused yearly great economic losses and is considered as a serious biosecurity threat to Tunisian date’s production and industry. It caused loss of weight and downgrading of the commercial value of dates. Current available postharvest control methods are mainly based on the use of synthetic fumigants. However, most of the available fumigants have limitations in use due to various reasons including environmental drawbacks (residues, contamination …) and the development of resistance in pest species. Consequently, the use of such chemicals began to be restricted and even banned outright. Therefore, research on effective alternative methods is needed. This paper reported results of several trials conducted using some essential oils derived from rosemary (Rosmarinus officinalis) for the control of the last instar larval stage of E. ceratoniae. Last instars developing inside fruit were treated with R. officinalis essential oil at 15, 25 and 75 μl/l air and mortalities were assessed after 7, 15 and 30 days of storage. Moreover, the impact of the essential oil on physic-chemical and organoleptic proprieties was investigated. Results indicated that the oil exhibited strong fumigant potentialities. Moreover, the oil affected nutritional properties of dates. Furthermore, sensory analysis showed acceptability and appreciation of dates treated with R. officinalis oil. Our results suggest R. officinalis oil to be a potential date protectant for the carob moth E. ceratoniae management in stored dates.