In order to identify the species of Helicotylenchus Steiner, 1945 present in Iran, 497 soil and root samples were collected from the rhizosphere of different plants and localities throughout the country during 2009-2010. A new and several known species of Helicotylenchus were identified from the collected material. H. persiaensis sp. n. is characterized by its short tail (8-11 µm , c = 54.2-79....

dutch elm disease is one of the most destructive and common plant vascular diseases now which isknown as a global problem. the aim of this study was comparison of early- and late-wood vesselsdiameter and ray dimensions. in 4 species: ulmus carpinifolia, zelkova carpinifolia, ulmus glabra andceltis australis from ulmaceae. then, very thin transversal sections were prepared and after differentsta...

Sooty mold fungi are often associated with honeydew which insects secrete while feeding on the plant. A great variety of these fungi occur in the North of Iran, especially on Citrus ssp which is one of the most widely cultivated fruit trees in this region. During last 10 years, several collections of these fungi examined and 15 species have been recorded. In this paper seven previously unreport...

zelkova carpinifolia is native to the alborz mountains in iran. it is a deciduous tree growing 20-35 m tall, with a trunk of up to 2 m in diameter. during the winter of 2011 cankers and dieback of branches were most commonly seen on zelkova trees in the daland forest in golestsn province. cankers were enlarged and severely led to decline in march. distinctive symptoms, assumed to be caused by a...