Grapes have the longest history of all the cultivated fruits and are among the most widely grown. Cooler temperatures and high relative humidity and/or moisture favour the development of fungal diseases of grapes. These diseases affect the leaves, shoots, stems and fruit. Fungal diseases can render fruit unusable and can very easily cause severe losses in yield. Grapevines are fairly adaptable plants, growing in a wide variety of soil types, from light sand to packed clay, and flourishing around the globe in the temperate bands between 20° and 50° latitude, north or south of the Equator. Black rot (Guignardia bidwellii (ELL.) V. et R. (anamorph: Phyllosticta ampelicida (Engelm.) van der Aa), white rot (Metasphaeria diplodiella (Viala et Ravaz) Berl. anamorph: Coniella diplodiella (Speg.) Pet. et Syd.), powdery mildew (Uncinula necator (Schein.) Burr. anamorph: Oidium tuckeri Berk.), downy mildew (Plasmopara viticola (Berk. & Curt. ex. de Bary) and grey mould (Botrytis bunch rot – B. fuckeliana (de Bary) Whetzel) are the most common fungal diseases of grapevine. Recently, decline symptoms (Phaeomoniella chlamydospora (W. Gams, Crous, M. J. Wingf. & L. Mugnai) in young grapevines have increased in areas with new planted vineyards resulting in poor vineyard establishment. In this review we describe symptoms of disease and their management, and the effect of climatic factors.

Grapevine is a foremost vegetative disseminated berry with high global socioeconomic prominence. It is vulnerable to numerous graft-transmitted agents that cause several diseases and extensive crop fatalities, decreasing fruit quality, plant strength, and also reduce the durability of vines. The vegetative transmission and frequent exchanges of propagative material within countries contribute to unfold these pathogens, esteeming the development of multifaceted diseases. Its lasting life cycle further accelerates the blending and introduction of numerous epidemiologic agents into a single plant. At present, almost 65 viruses belonging to different families have been reported infecting grapevines, however, all do not cause economically significant diseases. Regrettably, there are several breeds of vine diseases that prosper in all circumstances. Bacteria and fungi are a source of most common grapevine diseases. Insects can also propagate viruses and harm roots. Ecological circumstances can cause mold development that inflicts disorder on grapevines in vineyards. Here, we review the recent knowledge of these viruses, report advances in their diagnosis and prospection of new species, and give indications about the management of the associated grapevine diseases.

The effects of two training systems and row spacing on development of powdery mildew caused by Uncinula necator on clusters of 'Chardonnay' and 'Cabernet Sauvignon' grapevines were examined. Disease development was monitored in blocks with two different row spacing (2 and 3 m) in vertical shoot positioned vines (VSP) and in free-positioned, topped vines (FC) with no foliage support wires.

Alimad N., Naffaa W. and Azmeh F. 2017. Susceptibility of some local grape varieties cultivated in southern Syria to powdery mildew caused by Erysiphe necator Schwein. Arab Journal of Plant Protection, 35(1): 36-42. The Arab Journal of Plant Protection. 35 (1): 36 – 42. Powdery mildew, caused by Erysiphe necator Schwein is one of the most important fungal disease of grapevine worldwide, including Syria. Although the application of chemical fungicides is the most common control method, the use of resistant varieties is considered the most effective and environmentally sound strategy for managing the disease. The aim of this study was to evaluate the susceptibility of five local grape varieties cultivated in southern Syria to powdery mildew under artificial inoculation. The results showed that young leaves, mostly from the first to the sixth leaf, were the most susceptible, whereas older leaves were resistant or less susceptible. The incubation period was relatively short and did not exceed three days in young leaves, whereas it reached 14 days in the older leaves. According to the assessment scale used in this study, “Salty” and “American” varieties were highly resistant (HR), “Halwani” variety was susceptible (S), whereas “Baladi” and “Aswad” varieties were highly susceptible (HS). This is the first report on variation in susceptibility of Syrian local grape varieties to powdery mildew, and the resistant varieties identified could have potential use by breeders as sources of powdery mildew resistance

This study was conducted to evaluate the susceptibility of grapevine varieties to powdery mildew. Powdery mildew is a disease caused by a fungal, Erysiphenecator, and an obligate parasite of grapevine (Vitisvinifera L.). Powdery mildew causes drastic yield losses of 50 to 70%. Commercial grapevines grown in producing countries are susceptible to powdery mildew. Use of fungicides to control the disease is expensive and not environmentally friendly. Therefore, use of grapevine resistant varieties to powdery mildew is cost-effective control method. In this study, ten varieties (Black rose, Regina, Queen of Vineyards, Alphoncelavallee, Makutupora red, Chancellor, Halilibelyji, Syrah, Ruby seedless and Makutupora white) were screened for resistance to powdery mildew, using artificial inoculation of spore suspension and dry inoculums. Infected grape leaves were sampled from the field and grounded to obtain powder which was used as dry inoculum. The spore suspension inoculum was made by mi...