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Aphid predator (Hemiptera : Miridae)
Deraeocoris lutescensOn this page: Identification & Distribution Biology & Ecology Biological Control of Aphids
Identification & Distribution
Adult Deraeocoris lutescens (=Deraeocoris punctulatus) are usually orange-brown with blackish margins (see pictures below). The hemelytron membrane of Deraeocoris bugs has no hairs, but the remainder of the forewings have short fine hairs. The scutellum has two dark bars, and unlike the rest of the dorsal surface is unpunctured. The adult body length of males is 3.8-4.3 mm and of females 4.0-4.6 mm. The larvae are grey-green and covered with truncate black hairs.
Deraeocoris lutescens is zoophagous and phytophagous, predating small invertebrates including aphids, and also probing the leaves of trees and some herbaceous plants such as nettles. It occurs in southern Britain and central and southern Europe.
Biology & Ecology
We have found no references to the species of aphids eaten by this species, but given the range of plant hosts, prey selection is most likely opportunistic and non-specific. The eggs are laid deep in the young woody growth of various deciduous trees in late May and June. Most larvae reach the adult state in August and early September, and overwinter as adults.
Azimizadeh et al. (2012a) studied the oviposition site preference of Deraeocoris lutescens. Among different plant species, most oviposition was on broad bean leaves. In order to determine oviposition preference, broad bean leaves were infested with different prey and treated with other nutritional sources. Adult Deraeocoris lutescens females preferred leaves infested with the aphid Myzus persicae to those with other nutritional sources. Leaves in dark areas were preferred over leaves in the light.
Lamine et al. (2005) evaluated the impact that hunger has on the searching behaviour of Deraeocoris lutescens. The bugs were fed a diet of Rhopalosiphum padi nymphs and Ephestia kuehniella (Mediterranean flour moth) eggs. Results showed an effect of starvation on the searching paths of Deraeocoris lutescens nymphs and adults. Satiated third instar nymphs manifested an intensive search path, whereas fifth instar nymphs, and adults, adopted an intermediate one. When starved, the extensive search path appeared early in young nymphs, and later in the last instar nymphs and adults, according to the degree of prey deprivation.
Biological control of Aphids
Deraeocoris lutescens is regarded as a general predator in European orchards. It is mainly known as egg predator of the pear psyllid, Cacopsylla pyri (Herard, 1986 ). Arcanin and Balarin, 1972 , and from traditional apple orchards in Britain by Lush, 2009 reported Deraeocoris lutescens as an aphid and mite predator from apple orchards in Croatia. Lamine (2004) suggested it had great potential as a predator in hazel orchards.
Zadeh & Parvar (2014a) carried out greenhouse experiments in order to assess the efficiency of Deraeocoris lutescens for the biological control of Myzus persicae on protected sugar beet plants. The mean number of the aphid individuals per plant was significantly higher in the control treatment than in the treatments with Deraeocoris lutescens - where the number of the prey decreased gradually till it reached zero in the 5th week. This predatory bug was able to reproduce on sugar beet plants in the absence of prey. Zadeh & Parvar (2014b) developed ways to mass produce Daerocoris lutescens for biological control purposes.
Azimizadeh et al. (2012b) investigated the susceptibility of Deraeocoris lutescens to seven common pesticides: abamectin, fenpropathrin, imidacloprid, pirimicarb, spirodiclofen, thiacloprid and penconazole. Penconazole and pirodiclofen caused the least mortality on different life stages of the predatory bug. The highest mortality was caused by fenpropathrin, imidacloprid and hiacloprid. These latter three also had the most harmful residues.