Monitoring physiological races ofPodosphaera xanthii (syn.Sphaerotheca fuliginea), the causal agent of powdery mildew in cucurbits: Factors affecting race identification and the importance for research and commerce

  title={Monitoring physiological races ofPodosphaera xanthii (syn.Sphaerotheca fuliginea), the causal agent of powdery mildew in cucurbits: Factors affecting race identification and the importance for research and commerce},
  author={Ronit Cohen and Yosef Burger and Nurit Katzir},
Identification of the physiological races ofPodosphaera xanthii (syn.Sphaerotheca fuliginea), the causal agent of powdery mildew in cucurbits, is based upon the differing responses of various melon cultigens to the pathogen. Eight races of the pathogen have been identified to date in the USA, Africa, Europe and around the Mediterranean Sea, and four new races were reported from greenhouse melons in the major growing area of Japan. Plant responses to powdery mildew may be affected by… 

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Detailed description of the cucurbit powdery mildew pathogen and race classification system is provided and screening and selection studies against powResearch Article Open Access Res.


Cucurbits comprise a group of plant species of great economical interest for the increase of food production such as cucumber, melon and squash but some favourable conditions for the development of diseases, like the cucurbit powdery mildew, occur.

Cucurbit powdery mildew of melon incited by Podosphaera xanthii: global and western U.S. perspectives.

The gradual increase in the complexity of Pxand Gc-melon interactions over 87 years is reviewed, expressed as pathogenic races, which has recently escalated.



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Race identification in powdery mildew (Sphaerotheca fuliginea) on melon (Cucumis melo) in Japan

Results suggest that the resistance gene to races 1 and 5 of S. fuliginea should be introduced into the breeding materials in Japan.

Genetic differentiation in the French population of Erysiphe cichoracearum, a causal agent of powdery mildew of cucurbits

The relative incidence of Erysiphe cichoracearum and Sphaerotheca fuliginea, both agents of powdery mildew of cucurbits, was determined andGametic disequilibrium analysis among RAPD loci and biological observations suggest that the sexual stage is of minor importance for epidemics of E. cich oracearums on cucurbit.

Single-gene resistance to powdery mildew in zucchini squash (Cucurbita pepo)

Resistance to cucurbita pepo powdery mildew is conferred by a single incompletely dominant gene, designated Pm-0.

Impact of resistant melon cultivars on Sphaerotheca fuliginea

The results suggest that, although the resistant cultivars of melon are extremely effective for protecting the plants from their respective races, a race succession rapidly takes place, even in a small area, and other minor races become predominant.

Causal agents of powdery mildew of cucurbits in Sudan

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