03424cab a2200313Ia 45 0 u211489 SIRSI 101023s2015 ua ss b eng d EAL eng ara ART MJAR V40 No4 Pt1 2 Radwan, Fatma M. Minufiya journal of agricultural research, 2015 v.40 (4) Part 1 [electronic resource]. Powdery mildew of grapevine in Egypt [electronic resource]: prevalence, temperature, humidity, cultivars and chemical and biological control. البياض الدقيقي علي العنب فى مصر: تفشي المرض، الحرارة ،الرطوبة الأصناف ومكافحته كيماويا وبيولوجيا. P.901-913. Includes references. Field studies were conducted to clarify the period of the disease appearance and its successive development. Thompson seedless, Crimson seedless, Red Roomy and Flame seedless cu/tivars in four Egyptian governorates, i.e. Kalyoubia, Gharbia, Beheira and Minia were examined during 2012 and 2013seasons to calculate the disease severity%. The disease occurrence was more prevailing during the season 2013 than 2012. Flame seedless was the least susceptible cultivar, Thompson seedless, Red roomy and Crimson seedless were very susceptible under field conditions. In the contrary, the highest disease severity was recorded in Gharbia on Red Roomy and Crimson seedless but the lowest was on Thompson seedless and Flame seedless. The highest disease severity percentage was recorded in Minia governorate with all cultivars, followed by Beheira and Kalyoubia, while Gharbia governorate recorded the lowest occurrence. The temperatures which were correlated with the intensity of powdery mildew indicating that as temperatures increase, the intensity increased. The pathogenic activity of the fungus began when the temperature was 22 °C with a relative humidity more than 50%. The temperature of 25.0-32.0°C, relative humidity of 55-90% were the most favourable conditions for the peak incidence of the disease. Interestingly, the disease.severity subsided with the increasing the temperature degree above32 °C. The fungicides and biocides were sprayed 5 times at 15-day intervals at two programmes on grapevine cv. Thompson seedless in Nobaria-Beheira . All treatments in early spraying programme which started with three protective sprays of sulfur after bud break were more effective on leaves and bunches as compared with treatments were used in late spraying programme which started after the appearance of disease symptoms. Topas, Bayfidan and Punch were the most effective treatments, followed by Topsin Mand AQ10. On the contrary, Bio Arc, Bio Zeid and Micronized soreil were the least in minimizing the incidence of powdery mildew. The efficiency of sulfur declined when the pressure of the disease was high. Summary in Arabic. Grape powdery mildew disease Biological control. Uncinula necator. Fungicides. Grapes Diseases and pests Biological control. Radwan, M. A. Hassan, M. S. S. Minufiya Journal of Agricultural Research. 2015.v.40(4) Part 1 1110-0265 nnas u158151 http://nile.enal.sci.eg/EALE/2015/MJAR/4015/4/P1/901.pdf Full Text Article 1 AR lcc 60489 60489