PARASITOIDS (HYM, APHELINIDAE) OF THREE SCALE INSECTS (HOM, DIASPIDIDAE) IN A CITRUS GROVE IN VALENCIA, SPAIN

摘要

The parasitoids of Aonidiella aurantii (Maskell), Lepidosaphes beckii (Newman) and Parlatoria pergandii Comstock were studied in a Navel orange grove in Valencia, Spain during three years. Four species of Aphytis were identified on yellow sticky traps, Aphytis chrysomphali (Mercet), Aphytis melinus Debach, Aphytis lepidosaphes Compere and Aphytis hispnnicus (Mercet). No consistent annual pattern was observed in the flight of adults. A. melinus, introduced some years earlier in the grove, was found in very low numbers and showed no signs of increasing and displacing A. chrysomphali as a parasitoid of A. aurantii. On female scales of the three species sampled at regular intervals from leaves, twigs and fruit, the mean annual rate of active parasitism was similar and ranged from 3.5% to 8%. P. pergandii males were not parasitized, in L. beckii parasitism was usually much lower in male than in female scales, and in A. aurantii it was higher in the males. Scales of the three species were less parasitized on twigs than on leaves, and so were L. beckii on fruit. The annual trend of parasitism by Aphytis on scales fluctuated without a definite pattern. Parasitism by Encarsia inquirenda (Silvestri), an endoparasitoid of P. pergandii, was more stable throughout the year and increased steadily from year to year.