Biological Control of Take-all of Wheat in the Pacific Northwest of the USA Using Hypovirulent Gaeumannomyces graminis var. tritici and Fluorescent Pseudomonads

Five isolates each of actinomycetes, bacteria and fluorescent pseudomonads from the roots of wheat were tested for antagonism against Gaeumannomyces graminis var. tritici on agar and in sterile and unsterile soil. There was no apparent correlation between the tests. Effects on the growth of the take-all fungus (TAF) on agar ranged from nil to various degrees of colony deformation and/or inhibition. In a sterile sandy subsoil growing wheat seedlings, all except one isolate had no effect on disease production by a straw inoculum of the TAF. In an unsterile soil, however, measurements of shoot weight indicated that disease was reduced by all five isolates of bacteria singly and in mixture and by four of the five isolates of actinomycetes and a mixture of all five. Although a mixture of all five isolates of fluorescent pseudomonads reduced the disease, none of them produced a similar effect when tested singly. In the absence of the pathogen none of the test organisms significantly increased the shoot weight of wheat.

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Evaluation of some antagonistic bacteria in biological control of Gaeumannomyces graminis var tritici causal agent of wheat take-all disease in Iran

African Journal of Microbiology Research ◽

10.5897/ajmr11.789 ◽

2011 ◽

Vol 5 (29) ◽

Cited By ~ 1

Author(s):

Elahe Babaeipoor,

Keyword(s):

Biological Control ◽

Causal Agent ◽

Gaeumannomyces Graminis ◽

Antagonistic Bacteria ◽

Gaeumannomyces Graminis Var Tritici ◽

Take All

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First field records of Pachycrepoideus vindemiae as a parasitoid of Drosophila suzukii in European and Oregon small fruit production areas

Entomologia ◽

10.4081/entomologia.2013.e3 ◽

2013 ◽

pp. e3 ◽

Cited By ~ 32

Author(s):

M.V. Rossi Stacconi ◽

A. Grassi ◽

D.T. Dalton ◽

B. Miller ◽

M. Ouantar ◽

...

Keyword(s):

Biological Control ◽

Pacific Northwest ◽

Fruit Production ◽

Drosophila Suzukii ◽

New Host ◽

The Pacific ◽

The Status ◽

The Usa ◽

Set Up ◽

Study Sites

Drosophila suzukii (Matsumura) (Diptera: Drosophilidae) is a destructive crop pest native to Southeast Asia that recently invaded countries in Europe and North America, severely impacting commercial fruit production in its new host range. Here we report the results of a survey aimed at determining the presence of indigenous D. suzukii parasitoid populations carried out from May to October 2012 in two areas negatively affected by this fruit pest: Trento Province, Northern Italy, and Oregon in the Pacific Northwest of the USA. We conducted field and laboratory studies in order to determine the status of biological control agents utilizing D. suzukii as a host. Our study sites included a range of commercial soft fruits and natural non-commercial habitats. In each site, sentinel traps were baited with either D. suzukii or Drosophila melanogaster Meigen (Diptera: Drosophilidae) larvae in different food substrates. The generalist parasitoid, Pachycrepoideus vindemiae (Rondani) (Hymenoptera: Pteromalidae), was collected from both D. suzukii and D. melanogaster pupae in traps deployed in a selection of these sites. This report of P. vindemiae in 2012 represents the first identification of D. suzukii parasitoids in Europe. A successive parasitism efficacy test was set up under controlled laboratory conditions confirming the ability of P. vindemiae to attack D. suzukii pupae. In addition, an historical digression with analysis of the original documents in the Italian archives has been provided in order to unravel the correct species name. We finally discuss the possible practical implications of this finding for the biological control of D. suzukii.

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Isolation, Characterization, and Sensitivity to 2,4-Diacetylphloroglucinol of Isolates of Phialophora spp. from Washington Wheat Fields

Phytopathology ◽

10.1094/phyto-100-5-0404 ◽

2010 ◽

Vol 100 (5) ◽

pp. 404-414 ◽

Cited By ~ 6

Author(s):

Youn-Sig Kwak ◽

Peter A. H. M. Bakker ◽

Debora C. M. Glandorf ◽

Jennifer T. Rice ◽

Timothy C. Paulitz ◽

...

Keyword(s):

Sequence Comparison ◽

Phylogenetic Trees ◽

Washington State ◽

Gaeumannomyces Graminis ◽

Wild Oat ◽

Genetic Characteristics ◽

Oat Cultivars ◽

Eastern Washington ◽

Gaeumannomyces Graminis Var Tritici ◽

Take All

Dark pigmented fungi of the Gaeumannomyces–Phialophora complex were isolated from the roots of wheat grown in fields in eastern Washington State. These fungi were identified as Phialophora spp. on the basis of morphological and genetic characteristics. The isolates produced lobed hyphopodia on wheat coleoptiles, phialides, and hyaline phialospores. Sequence comparison of internal transcribed spacer regions indicated that the Phialophora isolates were clearly separated from other Gaeumannomyces spp. Primers AV1 and AV3 amplified 1.3-kb portions of an avenacinase-like gene in the Phialophora isolates. Phylogenetic trees of the avenacinase-like gene in the Phialophora spp. also clearly separated them from other Gaeumannomyces spp. The Phialophora isolates were moderately virulent on wheat and barley and produced confined black lesions on the roots of wild oat and two oat cultivars. Among isolates tested for their sensitivity to 2,4-diacetylphloroglucinol (2,4-DAPG), the 90% effective dose values were 11.9 to 48.2 μg ml–1. A representative Phialophora isolate reduced the severity of take-all on wheat caused by two different isolates of Gaeumannomyces graminis var. tritici. To our knowledge, this study provides the first report of an avenacinase-like gene in Phialophora spp. and demonstrated that the fungus is significantly less sensitive to 2,4-DAPG than G. graminis var. tritici.

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Gaeumannomyces graminis var. tritici. [Descriptions of Fungi and Bacteria].

IMI Descriptions of Fungi and Bacteria ◽

10.1079/dfb/20056400383 ◽

1973 ◽

Author(s):

J. Walker

Keyword(s):

Geographical Distribution ◽

Root Hairs ◽

Seed Transmission ◽

Gaeumannomyces Graminis ◽

Root Infection ◽

Root Death ◽

Meristematic Region ◽

Germ Tubes ◽

Gaeumannomyces Graminis Var Tritici ◽

Take All

Abstract A description is provided for Gaeumannomyces graminis var. tritici. Information is included on the disease caused by the organism, its transmission, geographical distribution, and hosts. HOSTS: Gramineae, especially Triticum, Hordeum, Secale, Agropyron and several other grass genera and, more rarely, Sorghum and Zea; also recorded from the roots of plants in other families. DISEASE: Take-all of cereals and grasses (also referred to as deadheads or whiteheads, pietin and pied noir (France), Schwarzbeinigkeit and Ophiobolus Fusskrankheit (Germany), Ophiobolusvoetziekt (Netherlands) and others). Root infection is favoured by soil temperature from 12-20°C (Butler, 1961). Ascospore germ tubes penetrate root hairs and the epidermis in the meristematic region (Weste, 1972) leading to plugging of xylem and root death. GEOGRAPHICAL DISTRIBUTION: (CMI Map 334, ed. 3, 1972). Widespread, especially in temperate zones. Africa; Asia (India, Iran, Japan, USSR): Australasia and Oceania; Europe; North America (Canada, USA); South America (Argentina, Brazil, Chile, Colombia, Uruguay). TRANSMISSION: In soil on infected organic fragments, as runner hyphae on roots of cereals and grasses and, under special conditions, by ascospores. Seed transmission very doubtful (47, 3058).

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