Cerato-ulmin: A Unique Wilt Toxin of Instrumental Significance in the Development of Dutch Elm Disease

1993 ◽  
pp. 89-151 ◽  
Author(s):  
Wayne C. Richards
Keyword(s):  
Dutch Elm Disease

Studies on the Fungal Pathogen of Dutch Elm Disease

1981 ◽  
Vol 39 ◽  
pp. 400-401
Author(s):  
H.M. Mazzone ◽  
G. Wray ◽  
R. Zerillo
Keyword(s):  
Fungal Pathogen ◽  
Fungal Growth ◽  
Polymyxin B ◽  
The United States ◽  
Dutch Elm Disease ◽  
Effective Control ◽  
Sabouraud Agar ◽  
Total Inhibition ◽  
Zones Of Inhibition ◽  
Control Plate

The fungal pathogen of the Dutch elm disease (DED), Ceratocystis ulmi (Buisman) C. Moreau, has eluded effective control since its introduction in the United States more than sixty years ago. Our studies on DED include establishing biological control agents against C. ulmi. In this report we describe the inhibitory action of the antibiotic polymyxin B on the causal agent of DED.In screening a number of antibiotics against C. ulmi, we observed that filter paper discs containing 300 units (U) of polymyxin B (Difco Laboratories) per disc, produced zones of inhibition to the fungus grown on potato dextrose agar or Sabouraud agar plates (100mm x 15mm), Fig. 1a. Total inhibition of fungal growth on a plate occurred when agar overlays containing fungus and antibiotic (polymyxin B sulfate, ICN Pharmaceuticals, Inc.) were poured on the underlying agar growth medium. The agar overlays consisted of the following: 4.5 ml of 0.7% agar, 0.5 ml of fungus (control plate); 4.0 ml of 0.7% agar, 0.5 ml of fungus, 0.5 ml of polymyxin B sulfate (77,700 U). Fig. 1, b and c, compares a control plate and polymyxin plate after seven days.

The Microscopy of Compatibility and Incompatibility in Ulmus

1985 ◽  
Vol 43 ◽  
pp. 504-505
Author(s):  
B. L. Redmond ◽  
Christopher F. Bob
Keyword(s):  
Dutch Elm Disease ◽  
Economic Losses ◽  
Hybrid Progeny ◽  
Ulmus Pumila ◽  
Ulmus Americana ◽  
American Elm ◽  
Asian Species ◽  
Ulmus Parvifolia ◽  
Initial Appearance ◽  
Chinese Elm

The American Elm (Ulmus americana L.) has been plagued by Dutch Elm Disease (DED), a lethal disease caused by the fungus Ceratocystis ulmi (Buisman) c. Moreau. Since its initial appearance in North America around 1930, DED has wrought inexorable devastation on the American elm population, triggering both environmental and economic losses. In response to the havoc caused by the disease, many attempts have been made to hybridize U. americana with a few ornamentally less desirable, though highly DED resistant, Asian species (mainly the Siberian elm, Ulmus pumila L., and the Chinese elm Ulmus parvifolia Jacq.). The goal is to develop, through breeding efforts, hybrid progeny that display the ornamentally desirable characteristics of U. americana with the disease resistance of the Asian species. Unfortunately, however, all attempts to hybridize U. americana have been prevented by incompatibility. Only through a firm understanding of both compatibility and incompatibility will it be possible to circumvent the incompatibility and hence achieve hybridization.

Fungi on leaves, branches and stems of trees and shrubs of Saint Petersburg suburban parks

2017 ◽  
Author(s):  
М.В. Сидельникова ◽  
А.В. Тобиас ◽  
Д.Ю. Власов
Keyword(s):  
Pathogenic Fungi ◽  
Dutch Elm Disease ◽  
City Center ◽  
Saint Petersburg ◽  
Xylotrophic Fungi ◽  
Fungi Infection ◽  
Mycological Examination ◽  
The Moment ◽  
Available Information ◽  
Trees And Shrubs

Проведены микологические обследования древесной и кустарниковой растительности на территории парковой зоны Санкт-Петербурга и пригородов. Сбор материала проводился в парках южных пригородов Санкт-Петербурга (Павловский парк, Екатерининский парк, Нижний сад и Верхний парк Ораниенбаума, Верхний сад и Нижний парк ГМЗ «Петергоф»). В сравнительных целях был обследован парк при Обуховской больнице в центре Санкт-Петербурга. На древесно-кустарниковых породах парковой зоны нами выявлено 230 видов грибов (микро- и макромицетов). На листьях выявлено 28 видов микромицетов, в числе которых возбудители мучнистой росы, ржавчины и пятнистостей. На ветвях и стволах древесных пород выявлено 150 видов микромицетов, среди которых есть как часто встречающиеся, так и редкие виды грибов. Большинство из них обнаруживается в анаморфной стадии. Наибольшее разнообразие и развитие микромицетов отмечено на сухих ветвях. Высокой вредоносностью характеризуются тиростромоз липы и голландская болезнь вязов. Выявлены устойчивые патогенные комплексы грибов, развитие которых приводит к заметному ухудшению состояния растений. На стволах живых и усыхающих деревьев, а также растительных остатках отмечено 52 вида макромицетов. Среди них выявлены доминирующие и редкие виды. Среди источников заражения древесных растений ксилотрофными грибами выделяются отмершие вязы, усохшие стволы которых можно наблюдать как в пригородных парках, так и в центральной части Санкт-Петербурга. Полученные данные существенно расширяют имеющиеся сведения по микобиоте парков Санкт-Петербурга. Mycological examination of tree and shrub vegetation on the territory of Saint Petersburg park zone and its suburbs was conducted. Material was collected in the parks of southern suburbs of Saint Petersburg (Pavlovsk Park, Catherine Park, Lower Garden and Upper Park in Oranienbaum, Upper Garden and Lower Park in Peterhof). For comparative purposes Park of Obukhov Hospital in Saint Petersburg city center was also examined. At the moment, 230 fungi species (micro- and macrofungi) were identified on trees and shrubs of the park zone. Among them, 28 species of microfungi, including powdery mildew, rust and blights pathogens were found on leaves. Also, 150 species of microfungi, including both common and rare fungi species, were found on branches and trunks. Most of them were found in the anamorphic stage. The greatest diversity and microfungi development were noted on dry branches. Thyrostromose of linden and Dutch elm disease are the most harmful. Stable complexes of pathogenic fungi, which development leads to clear decline of plants' condition, were identified. In addition, 52 species of macrofungi, including dominant and rare species, were observed on trunks of living and drying trees and vegetation residues. Among the sources of xylotrophic fungi infection of woody plants, dead elms are the most distinguished. Their dead trunks can be found in both suburban parks and the central part of Saint Petersburg. The presented data significantly expand available information on mycobiota Saint Petersburg parks.

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