الديناميكية الزمنية لمجتمع دودة ثمار التفاح و متطفلاتها الحشرية في منطقتين مختلفتين بجنوب سورية

الملخص EN

The dynamics of the apple codling moth, Cydia pomonella Linnaeus (Lepidoptera: Tortricidae) community and its parasitoids were studied in two areas known for apples cultivation in southern Syria, Khan Arnabeh (Quneitra Governorate) and Al-Harisa (Sweida governorate), located at different altitudes.

The synchrony of emergence between the insect parasitoids and its preferred host stage is essential for developing an effective biological control strategy for the insect in the two study areas.

The number of generations of the insect differed according to the study site, as the insect had three generations in Khan Arnabeh region, and two generations in Al-Harisa area.

The parasitoids that parasitize the different stages of the apple codling moth and the parasitism rate were evaluated by collecting apple fruits infested with insect larvae, and advanced larval samples were collected using cardboard zigzag traps that were installed in early June before the migration of the mature larvae to the bark fissures for pupation.

In this study, 8 species of parasitoids were recorded on Cydia pomonella in the two study sites, of which 8 species were found in Khan Arnabeh area with 100% parastism, and 7 species were found in the Al-Harisa area with 87.5% parasitism, and 7 species found in both areas with 87.5% parasitism.

The relationship between the collection method (from fruits or cartoon zigzag traps) and the insect generation was significant in the two study areas, results showed a difference in the parasitism rate on the larvae collected from fruits and on the larvae collected by the cartoon traps.

The parasitoid Ascogaster quadridentata Wesmeal (Hymenoptera: Braconidae) was an effective parasitoid in the management of the apple codling moth in the two study areas (Khan Arnabah and AL-Harisa) in southern Syria, due to the presence of a fairly high parasitism rate, even early in the season when pest control is most efficient.

However, the secondary parasite, Perilampus tristis (Mayr) (Hymenoptera: Perilampidae) limited the activity of A.

quadridentata in the two study areas.

Results also showed that the parasitoid A.

quadridentata was found during the egg stage of the insect, which is the period when the parasitism process begins, and that the parasitoid Ephialtes caudatus Ratzeburg was found during the fully developed larval stage of the insect.

This compatability between these two parasitoids and the host insect was due to their ability to identify the physiological status of the host insect, to estimate changes in the concentration of the ecdysteroids at the end of the host insect's development.

Keywords: Codling moth, Cydia pomonella Linnaeus, parasitoids, population dynamics, Syria.