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. 2009 Mar;10(2):153-60.
doi: 10.1111/j.1364-3703.2008.00527.x.

The powdery mildew fungus Podosphaera fusca (synonym Podosphaera xanthii), a constant threat to cucurbits

Alejandro Pérez-García  1 , Diego Romero, Dolores Fernández-Ortuño, Francisco López-Ruiz, Antonio De Vicente, Juan A Torés
Affiliations

The powdery mildew fungus Podosphaera fusca (synonym Podosphaera xanthii), a constant threat to cucurbits

Alejandro Pérez-García et al. Mol Plant Pathol. 2009 Mar.

Abstract

Numerous vegetable crops are susceptible to powdery mildew, but cucurbits are arguably the group most severely affected. Podosphaera fusca (synonym Podosphaera xanthii) is the main causal agent of cucurbit powdery mildew and one of the most important limiting factors for cucurbit production worldwide. Although great efforts have been invested in disease control, by contrast, many basic aspects of the biology of P. fusca remain unknown.

Taxonomy: Podosphaera fusca (Fr.) Braun & Shishkoff. Kingdom Fungi; Phylum Ascomycota; Subdivision Pezizomycotina; Class Leotiomycetes; Order Erysiphales; Family Erysiphaceae; genus Podosphaera; species fusca.

Identification: Superficial persistent mycelium. Conidia in chains, hyaline, ellipsoid to ovoid or doliform, about 24-40 x 15-22 microm, with cylindrical or cone-shaped fibrosin bodies, which often germinate from a lateral face and produce a broad, clavate germ tube and cylindrical foot-cells. Unbranched erect conidiophores. Cleistothecia globose, mostly 70-100 microm in diameter, dark brown/black. One ascus per cleistothecium with eight ascospores.

Host range: Angiosperm species that include several families, such as Asteracea, Cucurbitaceae, Lamiaceae, Scrophulariaceae, Solanaceae and Verbenaceae.

Disease symptoms: White colonies develop on leaf surfaces, petioles and stems. Under favourable environmental conditions, the colonies coalesce and the host tissue becomes chlorotic and usually senesces early.

Control: Chemical control and the use of resistant cultivars. Resistance has been documented in populations of P. fusca to some of the chemicals registered for control.

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Figures

Figure 1
Figure 1
Cucurbit powdery mildew symptoms caused by Podosphaera fusca. (A) Symptoms on a zucchini leaf. (B) Detail of a powdery mildew colony. (C) Zucchini cotyledon maintained in vitro and infected with P. fusca showing typical powdery mildew colonies.
Figure 2
Figure 2
Diagram depicting the life cycle of Podosphaera fusca.
See this image and copyright information in PMC

References

    1. Álvarez, B. and Torés, J.A. (1997) Cultivo in vitro de Sphaerotheca fuliginea (Schlecht. ex Fr.), efecto de diferentes fuentes de carbono sobre su desarrollo. Bol. San. Veg. Plagas 23, 283–288.
    1. Askary, H. , Benhamou, N. and Brodeur, J. (1997) Ultrastructural and cytochemical investigations of antagonistic effect of Verticillium lecanii on cucumber powdery mildew. Phytopathology, 87, 359–368. - PubMed
    1. Avis, T.J. and Bélanger, R.R. (2001) Specificity and mode of action of the antifungal fatty acid cis‐9‐heptadecenoic acid produced by Pseudozyma flocculosa . Appl. Environ. Microbiol. 67, 956–960. - PMC - PubMed
    1. Bardin, M. , Nicot, P.C. , Normand, P. and Lemaire, J.M. (1997) Virulence variation and DNA polymorphism in Sphaerotheca fuliginea, causal agent of powdery mildew in cucurbits. Eur. J. Plant Pathol. 103, 545–554.
    1. Bardin, M. , Suliman, M.E. , Sage‐Palloix, A.‐M. , Mohamed, Y.F. and Nicot, P.C. (2007) Inoculum production and long‐term conservation methods for cucurbits and tomato powdery mildews. Mycol. Res. 111, 740–747. - PubMed

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