Investigation of Suitable Time for Removal Vine Protection Soil to Prevent Frostbite Damage of Spring Reflection

According to the high dependence of the proceeds from the production of grape growers in many parts of the Iran, the occurrence of spring frosts can sometimes cause considerable losses in their annual livelihoods. Due to the development of grape vines in cold regions, many farmers use ‘Kazandeh’ training system, to protect the trunks and canes from freezing damage by the soil in the fall and winter seasons. The purpose of this investigation was to determine the best time for bringing out vines ‘BidaneSefid’ cultivar, from the subsoil from late winter to early spring. In addatin the buds have the least possible damage against the early spring frostbite. The experiment was conducted in two years (from March 2014 to April 2016) with Randomized Complete Block Design (RCBD) with 5 replications and 3 tratments in Khosbijan, Shazand, Iran. The treatments consist of removing out trunks and canes from the soil at three times included T1:16th March T2: 4th April T3: 24th April (as control). In the two years of the experiment occourred spring frostbite in dates of 26th April 2015 and 3th April 2016. In addition two artificial cold stages were applied on the buds of canes at temperatures of 0, -4, -8 and -12 ° C. In this research, Treatment T2 showed the lowest electrolyte leakage at artificial temperatures 0 to - 8 °C and percentage of sprouted buds was not significantly different between treatments after occourred spring frostbite. Furthermore in first year fruiting buds percent was higher in the treatment T1 compared to other treatments and in the order of time, the removal soil of vines, the soluble carbohydrates decreased, proline and the percentage of water content of the buds increased respectively. In second year buds soluble carbohydrate had the highest amount in treatment 2 when was measured at one time. In addition, soluble solid of fruit in this treatment was significantly higher than other treatments. Generally the best time to remove vines from under the soil was 4th April. This date, with regard to the process of temperature variation in two-year experiment coincided with the appropriate time for growth and a good percentage of fetal buds. Meanwhile, percentage soluble solids (TSS) in fruit at this date were significantly better from the other two treatments and fruits in this treatment had lower pH content and lower organic matter percentages. Generally the best time to remove vines from under the soil was 4th April. This date, with regard to the process of temperature variation in two-year experiment coincided with the appropriate time for growth and a good percentage of fetal buds. Meanwhile, percentage soluble solids (TSS) in fruit at this date were significantly better from the other two treatments and fruits in this treatment had lower pH content and lower organic matter percentages.