Effect of Soybean Oil and NAA Spraying on Vegatative Growth and some Quantitative and Qualitative Traits of Grape cv. Fakhri

This research was carried out in 2011 to evaluate the effect of blooming delay on growth and qualitative and quantitative traits in grapes cultivar Fakhri through a factorial experiment based on a randomized complete block design using soybean oil and Naphthalene acetic acid spraying. Treatments were time of spraying (March and April) and type and concentration of chemical compounds including distilled water (control), NAA at 100 and 200 mg/l, soybean oil at 5% and 10%, 100 mg/l NAA 10% soybean oil and 200 mg/l NAA % soybean oil. Soybean oil at 10% concentration, alone or in combination with NAA 100 mg/l, reduced branch length and diameter and decreased percentage of dead buds, compared to the control and auxin treatments. The highest and the lowest percentage of fruit set, number and weight of clusters were obtained from the control and 10% soybean oil alone or in combination with NAA, respectively. The application of 10% soybean oil resulted in larger berry size as well. Spraying vines in March was more effective in reducing number of clusters and berry weight, compared to the application of chemicals in April. However, fruit quality, except for soluble solid content, was not influenced by time of spraying. Delaying bud break for a relatively long period, through the application of soybean oil at 10% concentration, alone or in combination with NAA 100 mg/l, significantly reduced fruit quality to some extent which may be improved by delay in harvesting time.