Determination of releasing dosage of Aphytis Melinus Debach (Hymenoptera: Aphelinidae) for the biological control of California red scale, Aonidiella aurantii (Maskell) (Hemiptera: Diaspididae) in Turkey

Abstract

California red scale, Aonidiella aurantii (Maskell) (Hemiptera: Diaspididae) is a key pest of citrus in all growing regions of Turkey. Mass releases of Aphytus melinus DeBach (Hymenoptera: Aphelinidae) are conducted in Turkey for the biological control of the red scale. We studied the timing and releasing regime of the parasitoid.

The study was conducted in two orchards in Adana and Erzin (Hatay) in 2013 and 2014. Each orchard was divided in four equal areas. In each date we released 25000 and 50000 parazitoids per ha in two modalities: (i) 4 releases from April to June, (ii) multiple releases from April to October every 15 days.

There were no statistical differences in the scale infestation level between the two releases regimes. The infestation rate of the red scale on fruits before the release of A. melinus was 8% in Adana and 10% in Erzin; after releasing the infestation rate was 6% in 2013 and 4% in 2014 in Adana and 5% in 2013 and 5% in 2014 in Erzin. The population level of the red scale on the citrus leaves was different before and after release in both orchards. However, no significant differences were observed in the population level of the scale on branches.