Investigations on the parasites and predators of insects injurious to citrus orchards in the region of South Anatolia.
In 1973-74, surveys made on the parasites and predators of the arthropod pests on citrus in 12 orchards in different localities of the Mediterranean region of Turkey (southern Anatolia), and 33 species of insect pests, 4 mite pests, some 70 species of beneficial insects and 2 species of predacious mites (together with their hosts or prey) are listed. Since it was difficult to distinguish the activity of individual species of natural enemies on individual pest species, natural control was assessed of the major citrus pests such as Planococcus citri (Risso) (which is parasitised by Achrysopophagus sp., Anagyrus pseudococci (Gir.) and Leptomastidea abnormis (Gir.) and preyed upon by Scymnus spp., Hyperaspis polita Weise, Sympherobius sanctus Tjeder, Chilocorus bipustulatus (L.) and Orius minutus (L.)) and Aonidiella aurantii (Mask.) (which is parasitised by Aphytis chrysomphali (Merc.), A. melinus DeBach, Aspidiotiphagus lounsburyi (Berl. & Paoli) and A. citrinus (Craw) and preyed upon by Pharoscymnus ovoideus Sic. and P. pharoides (Mars.)).Different situations were found in different regions. The 2 pests mentioned were very common in the Adana district, with low populations of natural enemies, and the situation was further complicated by the location of the citrus orchards near cotton fields, where frequent insecticide applications prevented the development of populations of predators such as C. bipustulatus in the citrus orchards. In the Hatay and Icel districts, different pests (mostly scale insects and mites) were common, but except for Coccus spp. they were usually kept under control by their predators and parasites if the only sprays used were of light mineral oil without other chemicals. It is recommended that, (contrary to the current practice in Turkey of frequent organophosphate applications), oil sprays should be applied against scale insects, selective acaricides against mites and, if necessary, bait-sprays against the occasional outbreaks of Ceratitis capitata (Wied.), besides cultural measures, in order to take advantage as much as possible of natural control by beneficial insects.