الفهرس 
INTRODUCTIONOnly 14 pages are availabe for public view
 |  | from | 133 |  |  |
| | | from | 133 | | |
Abstract
This study was conducted during 2000 and 2001 seasons on head trained 15-years old White Banaty seedless grapevines grown in a private vineyard located at Minia district, Minia Governorate.
The objective of this study was examining the effect of spraying some micronutrients, GA3 and ascorbic acid on growth, yield as well as physical and chemical properties of White Banaty seedless grapevines.
The experiment included three factors, the first factor was the three concentrations of a mixture of micronutrients containing Zn, Fe and Mn in sulphate form at 0.0, 0.2 and 0.4 %. The second factor involved the three concentrations of gibberellic acid (GA3) at 0, 25 and 50 ppm. The third one involved three concentrations of ascorbic acid namely, 0, 500 and 1000 ppm. Therefore, the experiment consisted from seventy treatment, replicated four times, one vine per each. Completely randomized blocks design in a split-split arrangement was followed in this experiment. where the three concentrations of micronutrients, GA3 and ascorbic acid ranked the main plots, sub-plots and sub-sub plots, respectively.
The three micronutrients namely Zn, Fe and Mn in sulphate form at 0.2 to 0.4 % were sprayed three times once at growth start, just after berry set and at 20 days later. Gibberellic acid at 25 or 50 ppm was sprayed twice at 15 day interval after berry set and again at 15 days later. Clusters only were sprayed with GA3. Also, ascorbic acid was sprayed twice at growth start and again just after berry set.
For evaluating the effect of spraying micronutrients, GA3 and ascorbic acid on growth, yield and quality of Banaty grapes, the following parameters were determined.
Summary and Conclusion 89
0
1- Growth characters i.e. leaf area, cane thickness and pruning weight.
2- Yield expressed in weight (kg) and number of clusters per vine.
3- Weight, length and width of cluster.
4- Some physical characters of the berries included weight, volume, longitudinal and equatorial of berry.
5- Some chemical characters of the berries included total soluble solids %, total acidity %, total soluble solids /acid ratio and total sugars %.
The obtained results in both seasons could be summarized under
the following main topics.
1- Growth parameters
Spraying micronutrient mixtures containing Zn, Fe and Mn in sulphate form at 0.2 to 0.4 % and ascorbic acid at 500 to 1000 ppm were accompanied with improving leaf area, cane thickness and pruning weight compared to unspraying. The stimulation effect on growth characters was associated with increasing micronutrients and ascorbic acid concentrations. A slight promotion was detected among 0.2 and 0.4 % micronutrients, as well as 500 and 1000 ppm ascorbic acid. The
maximum values were detected on vines receiving three sprays of
micronutrients (Zn, Fe and Mn) at 0.4 % and two sprays of 1000 ppm ascorbic acid. The untreated vines produced the minimum values. Application of GA3 at 25 to 50 ppm had no effect on growth characters.
2- Yield
There was a remarkable promotion on yield expressed as weight (kg) and number of clusters per vine with application of Zn + Fe + Mn at 0.2 to 0.4 % in sulphate form, GA3 at 25 to 50 ppm and ascorbic acid at 500 to 1000 ppm compared to unspraying. A progressive promotion on
Summary and Conclusion 90
the yield was observed with increasing micronutrients, GA3 and ascorbic acid concentrations. Meaningless increasing was observed on the yield among 0.2 and 0.4 % of micronutrients, 25 and 50 ppm GA3 as well as 500 and 1000 ppm ascorbic acid. Therefore, the recommended rate of micronutrients, GA3 and ascorbic acid for producing an economical yield was 0.2 % in sulphate form, 25 ppm and 500 ppm, respectively.
3- Weight, length and width of cluster
Weight, length and width of cluster were positively affected by application of Zn, Fe and Mn at 0.2 to 0.4 %, GA3 at 25 to 50 ppm and ascorbic acid at 500 to 1000 ppm compared to unspraying. There was a gradual promotion on such parameters with raising concentrations of these materials. The maximum values were detected on the vines receiving 0.4 % of micronutrients, 50 ppm GA3 and 1000 ppm ascorbic acid. The untreated vines produced the minimum values.
4- Some physical characters of the berries
There was a gradual promotion on weight, volume, longitudinal and equatorial of berry with increasing the concentration of micronutrients from 0.0 to 0.4, GA3 from 0 to 50 ppm and ascorbic acid from 0 to 1000 ppm. A slight promotion on such physical characters was observed among 0.2 and 0.4 % micronutrients, 25 and 50 ppm GA3 as well as 500 to 1000 ppm ascorbic acid. The best results with regard to physical characters of the berries were obtained due to spraying the vines with 0.4 % micronutrients, 50 ppm GA3 and 1000 ppm ascorbic acid. The minimum values were detected on untreated vines.
5- Some chemical quality of the berries
There was a great promotion on chemical quality of the berries in terms of increasing the total soluble solids, total sugars, and total soluble solids /acid ratio and in decreasing the total acidity with using micronutrients, and ascorbic acid compared to unspraying. The promotion
Summary and Conclusion 91
was correlated with the increase of micronutrients and ascorbic acid concentrations. Raising concentrations of micronutrients from 0.2 and 0.4% and ascorbic acid from 500 to 1000 ppm failed to show any measurable promotion on chemical quality of the berries. However, application of GA3 at 25 to 50 ppm was responsible for reducing the total soluble solids, total sugars, and total soluble solids /acid ratio and in increasing total acidity compared to unspraying. The effect was associated with increasing GA3 concentrations. No measurable influence on chemical quality of the berries was observed due to raising micronutrients from 0.2 to 0.4 %, GA3 from 25 to 50 ppm and ascorbic acid from 500 and 1000 ppm. The best results with regard to chemical quality of the berries were obtained due to supplying the vines with 0.2 % micronutrients, 0 ppm GA3 and 500 ppm ascorbic acid.
Conclusion
The best results with regard to yield and quality of White Banaty seedless grapes were obtained due to spraying a mixture of micronutrients containing Zn, Fe and Mn at 0.2 % in sulphate form aside from GA3 at 25 ppm and ascorbic acid at 500 ppm. Application of micronutrients done three times at growth start, just after berry set and at 30 days later.
Gibberellic acid was sprayed twice a year at 15 days after berry set and
again 15 days later, while ascorbic acid was sprayed twice a year at growth start and again just after berry set.