I. The Importance of Powdery Mildews. . . . . . . . 51 II. Life Cycle of Powdery Mildews . . . . . . . . . . . . . 53 A. Asexual Reproduction. . . . . . . . . . . . . . . . . . 53 B. Sexual Reproduction . . . . . . . . . . . . . . . . . . . 53 III. Interactions with the Host Plant . . . . . . . . . . . . 55 A. Influence on Host Metabolism. . . . . . . . . . . 56 B. Induced Susceptibility and Re...

Powdery mildews on over 40 plants in Bangalore were screened during July-December of 2003~2008. Isolates from mycoparasitised Oidium caesalpiniacearum of Bauhinia purpurea comprised Lasiodiplodia theobromae, in addition to Ampelomyces quisqualis. Koch's postulates were satisfied to establish the mycoparasitism of L. theobromae. This is the first report that L. theobromae acts as a mycoparasite ...

medicinal plants are infected by fungal diseases. a four years survey indicated that, there are various fungal infections in roots and shoots of several medicinal plants that grown in isfahan. lavender (lavandula angustifolia), rosemarry (rosmarinus officinalis) and viper’s bugloss (borago officinalis) plants were infected by fusarium oxysporum and f. solani on roots, showing wilting and eventu...

Molecular phylogeny suggests a close relationship of Asteraceae to the early evolution of Golovinomyces. The family Asteraceae, with a geographic origin in South America, expanded into the Northern Hemisphere, where it may have been infected by an ancestor of Golovinomyces, thus starting a close hosteparasite relationship. Using this event as a calibration point, we designed molecular clocks fo...

RNA expression profiling of obligately parasitic plant microbes is hampered by the requisite interaction of host and parasite. This can be especially problematic in the case of powdery mildews, such as Erysiphe necator (syn. Uncinula necator), which grow superficially but tightly adhere to the plant epidermis. We developed and refined a simple and efficient technique in which nail polish was us...

For plant pathogenic fungi, such as powdery mildews, that survive only on a limited number of host plant species, it is a matter of vital importance that their spores sense that they landed on the right spot to initiate germination as quickly as possible. We investigated a barley (Hordeum vulgare) mutant with reduced epicuticular leaf waxes on which spores of adapted and nonadapted powdery mild...

Fungal spores are continuously deposited on the leaf surfaces by wind impaction, sedimentation and rain wash-out from the atmosphere and splash-dispersal. They reside and act as asymptomatic mutualists, benign commensals or latent pathogens. A slight imbalance in this relation can lead to pathogenic phase of the fungi, resulting in a variety of symptoms on leaves viz. discoloration, blight, soo...

The Arabidopsis disease resistance (R) genes RPW8.1 and RPW8.2 couple the recognition of powdery mildew pathogens of this plant with the subsequent induction of a localized necrosis, or hypersensitive response (HR). The HR restricts the spread of the infection and renders the plant resistant. One-third of Arabidopsis plants transformed with a genomic fragment containing RPW8.1 and RPW8.2 develo...

The common powdery mildew plant diseases are caused by ascomycete fungi of the order Erysiphales. Their characteristic life style as obligate biotrophs renders functional analyses in these species challenging, mainly because of experimental constraints to genetic manipulation. Global large-scale ("-omics") approaches are thus particularly valuable and insightful for the characterisation of the ...