IMPACTS OF THE VARIETY OF POMEGRANATE FRUIT ON PREFERENCE AND PERFORMANCE OF ECTOMYELOIS CERATONIAE (PYRALIDAE) AND DEUDORIX LIVIA (LYCAENIDAE)

In Tunisia, pomegranate (Punica granatum L.) is an important crop both economically and culturally.The marketing quality of pomegranate fruit is mainly affected by two pests namely Ectomyelois ceratoniae (Zeller) and Deudorix livia (Klug).The present work aims to assess the biological parameters and life history variables of immature and adult stages of both pests together with their larval competition under controlled laboratory conditions (T = 30 1C; HR = 70 5%; 16L: 8D photoperiod).The rearing was carried out on three pomegranate varieties namely Guebsi, Tounsi and Gares collected from Gafsa oasis (Southwestern, Tunisia).Results indicated that the shortest larval development time of E. ceratoniae (31.9 days) was observed in Tounsi variety.Besides, the shortest larval period of D. livia was registered in Guebsi variety (23 days).Moreover, the lowest survival rate (around 40%) was observed in the first larval stage with all the pomegranate varieties used for insect rearing.For D. livia, the lowest survival rate was observed in the first (48%) and the second (52%) instars feeding on the Gares variety and in the fourth instar rearing on the Guebsi variety (55%).Under competitive conditions the larvae weights were lower than those obtained when larvae were reared separately.