Preliminary survey of economic insects and their insect predators in northern Iraq.Abstract :
A survey to identify economic insects of poplar trees was carried out during 2012 in Erbil province in northern of Iraq. Various sampling techniques were used to collect different stages of insects from all tree parts (root, stem, branches and leaves). The survey revealed the presence of 21 insect species belonging to 4 order and 12 families, including two species reported on poplar for the first time in Iraq; Chaitophorus albus M., Pemphigus bursarius L., and presence 6 species of insect predators. The intensity of infestation varied from regions to anther depending on tree age, agricultural practices and variation in food preferences for poplar trees by insects. The results of field study showed a highest percent by poplar lace bug, Monosteira unicostata M.R. on the plant parts of poplar trees, namely, black poplar, Populus nigra, euphratic poplar, Populus euphratica and hybridpoplar, Populus euramericana, with a mean reached (90, 95, 70, 90, 60, 80%), respectively, followed small borer stem, Melanphila picta Pall. (30%), and Capnodis miliaris K. (20%). While there was a lowest infestation for big borer stem, Capnodis miliaris K., and poplar leaf bite, Japanagromyza sp., with infestation (10 and 20%) on the euphratic poplar, followed Melanphila picta Pall. (20%) and Japanagromyza sp.(10%), on Hybridpoplar, respectively. Field study results showed there are different percentage of infestation according to the kind of insect, species of tree and the part of plant that has been infested. In both regions, the poplar lace bug were high infested on poplar trees with a mean (88, 83 and 75%) respectively, followed by, euphratic leaf gall, Egeirotrioza ceardi B. (75%), poplar gall aphid; Pemphigus bursarius L. (75%), P. lichtensteini T. (85%) and poplar leaf aphid, Chaitophorus albus M. (78%) 0n the poplar trees in this study, respectively, while a least infection showed of big borer stem, Capnodis miliaris K. and poplar leaf bite, Japanagromyza sp., with a mean reached (10 and 13%) on the euphratic poplar, in both region, respectively. On the other hands, results also showed presence numerous insects in the two regions studied, like, poplar leaf worm, Pseudoteleia squamodorella A., poplar leaf bond, Gypsonoma hapalosarca M., poplar aegeri moth, Parathrene tabaniformis, poplar twig bug, Apodiphus amygdale, scale poplar insect, Diaspidiotus caucasicus B., poplar leaf beetles, Chrysomela populi, poplar root beetle, Anomala dubia S., poplar root beetle, Adoretus irakanus O., small borer stem, Melanphila picta Pall., poplar leaf bond, Nycteola asiatica K., poplar leaf worm, Apatele aceris L., black poplar leaf larva, Cerura vinula L., poplar leaf crinkle psyllid, Camarotoscena speciosa F..The results showed a number of predators that attack insects and it is the highest density of predators where a total average 40.0, 53.3 and 33.7 insect on the studied species, while the average of population density for predators where followed, normal ant, Solenopsis inyicta (67.5) insect, lady bird, Coccinella septenpunctata L. (55) insect, syrfis flies, Syrphus corolla F. (48.3), predators bug, Orius laevigatus F. (45), mantis hours, Mantis religiosa L. (27.5) insect andaphid lion, Chrysopa spp.(21.6) insect. Generally, in this field survey, the percentage of the infestation were highly on black, euphratic and hybridpoplar trees in Koysinjaq region with a total average (45, 43, 43%) compared with insect infestations in Taq-Taq regions (42, 53, 37%), respectively.
Survey, economic insects, food preferences, poplar, Populus nigra, P. euphratica, P. euramericana, predators, Iraq.