Decline symptoms associated with lethal stem and branch canker stain along with root and collar rots were observed on 5- to 7-year-old roadside oriental plane trees (Platanus orientalis) in Diyarbakır, Turkey. Above-ground symptoms included leaf necrosis, leaf curling, extensive bluish or blackish staining of shoots, branches, stem bark, and wood surfaces, as well as stem cankers and exfoliation of branch bark scales. A general decline of the trees was distinctly visible from a distance. A Phytophthora/Pythium-like oomycete species with globose to ovoid, often papillate and internally proliferating sporangia was consistently isolated from the fine and coarse roots and stained branch parts and shoots. The pathogen was identified as Phytopythium litorale based on several morphological features. Partial DNA sequences of three loci, including nuclear rDNA internal transcribed spacer (ITS) and the large ribosomal subunit (LSU), and mitochondrial cytochrome c oxidase subunit II (coxII) confirmed the morphological identification. All P. litorale isolates were homothallic, developing gametangia, ornamented oogonia with elongate to lobate antheridia. Pathogenicity of P. litorale was tested by inoculation on excised shoots and by root inoculation on seedlings. P. litorale produced large lesions and blights on shoots in just 5 days and killed 100% of the seedlings in a month. This paper presents the first confirmed report of P. litorale as an important pathogen on a plant species causing branch and stem cankers, and root and collar rot, in and on P. orientalis, resulting in a rapid decline of trees and suggesting a threat to plane.

在土耳其迪亚巴克尔（Diyarbakır）的5至7岁的路边东方梧桐树（Platanus Orientalis）上观察到与致死茎和分支溃疡病以及根腐烂相关的下降症状。地上症状包括叶片坏死，叶片卷曲，枝条，树枝，茎皮和木质表面的广泛的蓝色或黑色染色，以及茎萎缩和分支树皮鳞片脱落。从远处清晰可见树木的总体下降。从细根和粗根以及染色的分支部分和枝条中始终分离出具有球形至卵球形，经常为乳头状和内部繁殖的孢子囊的疫霉/腐霉菌类卵菌种。病原体鉴定为基于几个形态特征的紫罗兰疫霉。三个基因座的部分DNA序列，包括核rDNA内部转录间隔区（ITS）和大核糖体亚基（LSU），以及线粒体细胞色素C氧化酶亚基II（cox II），证实了形态学鉴定。所有的滨海假单胞菌分离物都是同型的，正在发育的配子体，带有延长的卵形花丝的装饰性卵形。P的致病性。通过在切下的枝条上接种和在幼苗上进行根部接种来测试立陶宛。斜纹夜蛾在短短5天内就产生了大的病斑并枯萎了，一个月内杀死了100％的幼苗。本文介绍了第一份确认的报告斜纹假单胞菌是植物物种上的重要病原体，在东方假单胞菌内和上引起分支和茎枯萎以及根和领腐烂，导致树木迅速倒下并暗示对平面的威胁。