The Economic Importance of the Greater Date Moth, Arenipses sabella Hampson (Lepidoptera: Pyralidae)

Since the end of the twentieth century, field observations and farmers' complaint indicated that, Arenipses sabella (Lepidoptera: Pyralidae) became a major pest attacks the date palm trees. There is no any accurate data on the extent of economic damage and loss of yield. The aim of this study is to determine the extent of the spread of this pest and the nature of the damage and percentage of loss in the yield under El-Kharga Oasis conditions.
Different larval instars were observed in full activity status in the frond bases during mid-January. Unopened spadix of the date palm males recorded the earliest infestation during the last week of January. Meanwhile, slightly infestation was recorded on spathes of the females during the end of March.
Over 80% of the inspected date palm in El-Kharga Oasis was found infested with A. sabella. Bunch bases infestation with A. sabella larvae ranged between surface and ⁄or cut damage. Cut bunch bases (CBB) caused by the pest is considered as economic injury lead to bunch base broken and causeeffected damage to the  fruits and affect its quality. This usually happens during August when bunches are heavy enough and then these infested bunches are unable to bear their weight.   
During 2015 and 2016 seasons, the general average of the total and surface bunch bases infestations was 22.07 and 12.95% and 18.32 and 8.27%, respectively.
After examining 25 date palm groves during two successive seasons, it was observed that, the highest (CBB) per one date palm tree was 62.50%.
Throughout the first season, the cut bunch bases due to the greater date moth infestation ranged between 0.00 and 21.62% with an average of 9.12%.This ratio ranged between 3.73 and 18.61 % with an average of 10.05% during the second season. Under El-Kharga Oasis conditions, the main date palm cultivar (Saidi) suffered from A. sabella attacks where, the general average of the cut bunch bases was 9.58%. It can be said that, this value reflects economic damage and loss of the fruit yield.