Integrated management of pests and diseases of different poplar species and clones in Iran.

Iran is one of the countries with poor forest sources. As a result of severe consumption of forests due to human ambition and lack of accurate management, forest areas of the country are reducing rapidly. So, developing forests especially with planting fast growing trees like poplar is of great necessity for the country. Pests and diseases are among the factors that cause severe quantitative and qualitative damages on poplar trees. In some areas the damage level of these agents are so high that has made the farmers reluctant to plant poplar trees. So, it is necessary to control the damage causing agents by integrated control methods that are nature friendly and economically suitable and reduce the population of the damaging agents under the economical threshold level. Integrated pest management (IPM) is due to qualitative and quantitative identification of the ecosystem and considers the existing ruling factors among biotic factors and protecting the natural enemies of pests. The project was executed during ١٩٩٧_]٢٠٠٧ in the following provinces: Guilan, Chaharmahalva- Bakhtiari, Zanjan, Hamedan, Isfahan, Kermanshah, Kohgilouye-va-Boyer-Ahmad, Markazi, West and East Azarbaijan, Northern Khorasan and Tehran. Poplar pests fauna was studied on different native and exotic poplar species and clones, which were planted according to compared and selected popultum projects. In addition to field sampling of insects and mites (using Schneider and light traps or direct collecting), immature stages of some pests were reared in lace pockets. Some xylophagous pests were also collected on trunks of the infected trees fenced with lace. For evaluating susceptibility and resistance of different species and clones to important pests in each research station, relation of infected trees to healthy ones and the method of giving number to each infection rate for each stand was used. In antibiosis tests the study was done by planting cuttings of different clones in greenhouse or examining the poplar cuttings in laboratory conditions. The obtained data was statistically analyzed using SPSS and SAS softwares. Samples that could not be identified in the Protection Division were sent to other scientific centers in Iran or other countries for identification. As a result of these studies poplar arthropods fauna, containing ٢٠٠ species , was identified that some species were new for the scientific world (Aceria zanjani n. sp.) and some were reported for the first time from Iran, like Mycterothrips salicis, Empoasca (Asymmefrasca) decedens, the parasitic mite Libinia coccinellae and the parasitoid wasp Pachyneuron grande. Most important poplar pests were also identified in each province where the project was executed. In northern provinces Paranthrene tabaniformis, Melolontha melolontha and Cossus cossus as xylophagous pests, Monosteira unicostata and Pterocomma populneum as sucking pests and Melasoma populi, two leaf feeder weevils Platymicterus marmoratus and Clorophanus latipes, Starenematus compressicornis, Amorpha populi, Dicranura (=Cerura) vinula, Nycteola asiatica and Gypsonema aceriana as philophagous pests of poplar trees. In other provinces Melanophila picta, Phlleomyzus passerinii, Empoasca decipiens, gall inducing aphids Pemphigus spp., Chaitophorus spp. Camarotoscena fulgidipennis, Aeolesthes sarta, Monosteira unicostata, Melasoma populi, Lithocoletis populi and Zeugophora flavicollis are of important and economic pests on poplar. The two leaf feeder weevils are just collected from Guilan province and are not found in other parts of the country and xylophagous pests like Melanophila picta and Aoelesthes sarta are not collected from northern provinces of Iran. Biology of some important pests were studied in greenhause and field conditions of some regions where the project was executed. Biology of some pests like Melasoma populi, Monosteira unicostata, Melanophila picta and Aeolesthes sarta were studied in Tehran and Isfahan provinces. Biology, life cycle, feeding behavior and population variation of some important poplar pests like Paranthrene tabaniformis, Nycteola asiatica, Pterocomma populeum and Stearunematus compressicornis have also been studied in Guilan and Mazandaran provinces. Several parasitoids and predators have been collected from different parts of the country and identified that some of them are reported for the first time from Iran. Species of natural enemies of some poplar pests of the families Miridae, Coccinellidae, Anthocoridae and Chrysomelidae are collected and identified and effectivity of some of them like Oenopia conglobata L. and Chrysopela carnea on Monosteira unicostata and poplar aphids have been studied. Resistance and susceptibility of different native and exotic poplar species and clones to some important pests like poplar wooly aphid in field condition of Zanjan and Hamedan provinces, poplar grasshopper in Chaharmahal-va-Bakhtiari province, poplar leaf feeder beetle in Tehran province (Karaj) and poplar leaf feeder weevil and Paranthrene tabaniformisin Guilan province were calculated. In these studies significant statistical differences were proved among the studied species and clones to important pests of each region. Interaction of poplar species and clones and population density of natural enemies of some pests like poplar leaf feeder in field condition in Karaj and interaction of natural enemies of poplar wooly aphid on poplar species and clones have also been studied. On the basis of the obtained results an executive program has been planed for controlling poplar pests in nurseries and poplar plantations of the provinces where the project was executed.