Biscogniauxia mediterranea causes charcoal disease on Quercus castanifolia, Q. brantii and Zelcova carpinifolia in Iran. This report introduces wild almond (Amygdalus scoparia) as a new host species for B. mediterranea in Iran. In 2015, symptoms of dieback of A. scoparia trees were observed for the first time in the Lorestan Forests of Iran. The causal fungus B. mediterranea was recovered from cankered tissues and identified based on morphology, and sequence analysis. Pathogenicity tests on two-year-old A. scoparia plants showed that B. mediterranea could cause lesions.

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Zelkova carpinifolia belongs to the Ulmaceae. It is the only species from Zelkova genus that has been distributed and is native to Iranian forests. This tree species is one of the valuable species that is comprised of endangered plants. Nevertheless, the most of reservoirs of this species have been faced to problems that fungal disease is one of the important and lethal disturbance. This study was conducted to identify the main disturbance which has been resulted in Z. carpinifolia decadence in Daland forest reservoir, North of Iran. The study has ensured that O. novo-ulmi is the fungal pathogen in this forest reservoir. It can be reminded that this pathogen had been previously found in Ulmus genus which has been created devastating event in these noteworthy reservoirs. Some symptoms which were observed in field comprising flagging and wilting of leaves. Bark beetle galleries and occlusion of xylem vessels were the other evidence of fungal disease. In light of laboratory results, the fungi colony was fluffy, light-colored and fast-growing. The different shapes of fungi growth like white fibrous and flower shape or dark petaloid shape were observed. Mean colony diameters of O. novo-ulmi were 3.72 ±0.16 mm/day in the dark at 20 °C. Simultaneously, Microscopic analysis of sexual and asexual systems of O. novo-ulmi using a light microscope, a stereo microscope, and a scanning electron microscope revealed that it had morphological features of sporothix, pesotum, yeast-like and perithecium synanon morphology.

This research investigated the population density of infected trees with charcoal canker disease and the interaction across the severity of the disease on Quercus castaneifolia in Hyrcanian forests, north of Iran. We used twodimensional spatial analysis tools with data gathered in point-centred quarter format in 2013. We investigated the cooccurrence of the severity of the disease symptoms using the paired quadrat covariance analysis. The results showed that nearly 54% of the oak trees were affected by the disease so that the dead trees and high disease severity were strongly clustered at broader scales (800 m), the trees with only limited exudates and signs of the activity of Biscogniauxia mediterranea (De Not.) Kuntze occurred in the clusters away from the dead trees. The crown mortality and beetle-infested trees cooccurred with mortality and were strongly correlated. Also, the findings of this research showed that the density of trees per hectare was one of the influential factors on the damage severity of the charcoal canker disease, so that reducing the density could increase the damage severity of the disease.