الفهرس 
Title : Biological control of powdery mildew and breakdown dormancy buds of grapes under organic farming regulations in Egypt and Tunisia
AbstractOnly 14 pages are availabe for public view
 |  | from | 170 |  |  |
| | | from | 170 | | |
Abstract
Table grape is considered one of the most important fruit crops, either for local consumption, or for exportation. In subtropical countries such as Egypt and Tunisia, there is no adequate winter chilling to stimulate bud burst. Farmers, specially those aim to export their grape fruits, use to use chemical treatment with dormex (hydrogen cyanamide 2-5%) to break bud dormancy and use highly toxic substances to control powdery mildew disease. According to european organic regulation EC. 834/2007 and 889/2008, annex I and II, dormex is not allowed. The present work offers biological method can, replace dormex in organic farms. In addition, biological preparations and some natural chemicals, allowed in organic agriculture, against powdery mildew were used. In case of bud burst, bacillus subtilis, T. harzianum, streptomyces spp. and Saccharomyces spp. were selected from micro flora of dormant buds according to their efficacy in cellulose decomposition. Using these microorganism isolates either as single isolate or as mixture at different concentrations led to significant increase in number of bursted buds compare with control treatment (water). Positive correlation between concentrations of microorganism cell/ml and efficacy of treatment was detected. Mixture contains bacillus subtilis isolates B2+B3 (60x10⁴ c.f.u) showed the highest effect whereas the lowest effect was noticed when streptomyces sp. isolate (1) was used at concentration 20x104 c.f.u/m. Using microorganisms suspension as spraying showed less effect compare with using same suspension as brushing using soft brush