Scale insects recorded on ornamental plants in urban areas of Kermanshah , Iran

Scale insects (Hemiptera: Coccoidea) are serious pests of ornamental plants, and are becoming increasingly important in urban areas in Iran. Here, we report on the results of an initial survey of scale insects found on ornamental plants in Kermanshah City, Iran. A total of 15 species of scale insects were recorded: 7 Diaspididae, 3 Pseudococcidae, 3 Coccidae, and 2 Eriococcidae. Of these, three species, Diaspidiotus gigas (Thiem and Gernek), Chortinaspis subterranean (Lindinger) and Acanthacoccus insignis (Newstead) are new records for Iran. In addition, five other species are new to Kermanshah.


INTRODUCTION
Ornamental plants are widely used in urban areas for environmental management.The most obvious use is to control soil erosion by wind and water.Apart for their use as ground cover on eroded areas to reduce dust and glare, ornamental plants are also used to alleviate air pollution, heat buildup and noise pollution (Baiyewu et al., 2005).
Scale insects cause various problems on ornamental trees and shrubs.Large populations of scale insects can kill branches and even the whole trees due to large volumes of plant sap they consume thereby weakening the plants (Hanson and Miller, 1984).In addition, the sugar-rich honeydew produced by the Coccoidea provides a perfect medium for the growth of sooty mould (Ulgenturk and Canakcioglu, 2004).
Even though coccoids are common and economically important pests, the scale insect fauna of Iran has been poorly studied [ScaleNet search (Ben-Dov et al., 2010)].In the middle of the last century, Kaussari published many papers on armoured scales (Diaspididae) plus a monograph on the subtribe Aspidiotina, tribe Aspidiotini (Diaspididae) (Kaussari and Farahbakhsh, 1968).The first complete list of scale insects in Iran was published by Bodenheimer (1944), who reported 89 species.Much later, Kozár et al. (1996) published a more extensive checklist of 185 species.Moghaddam (1998), in her MSc thesis, surveyed the armoured scale fauna in Fars province (southern Iran) and found 36 species in 21 genera.Later, Moghaddam (2004) provided a list of Iranian scale insects in the Hayk Mirzayans Museum, including 70 species in 10 families.Recently, Takagi and Moghaddam (2005) studied twelve armoured scale insects occurring in Iran.Moghaddam (2006) studied the mealybug fauna of southern Iran, found 17 mealybug species.Moghaddam and Tavakoli (2010)   of scale insects fauna in Kermanshah, western Iran, and recorded 27 species in 6 families.The objective of this study was to survey the scale insect species and their distribution and host plants (shade and ornamental trees) in the city of Kermanshah, Iran and determine which are likely to be economical important species.

MATERIALS AND METHODS
Coccoid samples on infested plants were collected in different locations within Kermanshah city during 2009 to 2010.The specimens were removed from the host plants and placed either in 75% ethyl alcohol or in plastic bags and taken to the laboratory of the Department of Plant Protection, College of Agriculture, Razi University.The location, date and the host plant of each sample were recorded.Later, all specimens were mounted on microscope slides using the methodology of Hodgson and Henderson (2000).Some effort was made to identify each sample using a compound light microscope and the relevant literature.The Diaspididae specimens (both mounted and unmounted material) were sent to Prof. S. Tagaki for definitive identification (personal communication) and the remaining specimens were sent to Dr C. Hodgson (personal communication).
Among these species, the armoured scale Parlatoria oleae (Colvee) on Cerasus microcorpa, the mealybug Planococcus vovae (Nassonov) on Cupressus arizonica and Thuja orientalis, and the felt scale Eriococcus (Acanthococcus) spurious (Modeer) on Ulmus densa all occur in large populations throughout the region and are likely to be economically important.Additionally, this study found that P. oleae and Melanaspis inopinata (Leonardi) are both widely distributed on Rosacae.The main pest of conifers in urban areas, in Kermanshah, is the small pine scale, Leucaspis pusilla, which infests the needles on the lowest branches of Pinus sp.Planococcus vovae (Nassonov) and Planococcus ficus (Signoret) are common on Cupressaceae and Platanaceae in central city parks.
The grapevine scale Parthenolecanium persicae (Fabricius) occurs in small populations throughout the urban area on Acer sp., and is likely to be economically important, only in seedling nurseries and on young trees.

Table 1 .
Scale insect species found in Kermanshah, Iran.
*First record for Kermanshah; ** First record for Iran.