1. Egypt AND FRUIT QUALITY OF MIT GHAMER PEACH TREES.
EFFECT OF PACLOBUTRAZOL ON SHOOT GROWTH, YIELD
AND FRUIT QUALITY OF MIT GHAMER PEACH TREES.
Prof. Galal I. Eliwa
Pomology Department
Faculty of Agriculture
Damietta University
Egypt

2. INTRODUCTION
The principle commercial peach cultivar grown in Dakahlia Governorate is Mit Ghamer.
Trees of this cultivar were resulted from sexual seedlings.
producing strong vegetative growth during fruit growth phases .
Trees require much pruning and hand labor would be considerably high.

3. INTRODUCTION
A reduction in the competition between Shoots and fruits growth for nutrients should result in an improvement in fruit size and quality.
Also, exists to control tree size and
consequently simplify management operations such as fruit thinning and harvesting .
Many techniques have been used in an attempt to control vegetative growth of stone fruit, cincturing, regulated deficit irrigation and pruning.

4. INTRODUCTION
However, most of these techniques have been only partially successful in controlling tree growth
The growth retardant, paclobutrazol has shown promise in ;
controlling the growth of extension shoots
increased floral bud initiation ,
fruit numbers per tree and fruit size .

5. THE AIM OF THIS STUDY
To investigate the exact concentration of paclobutrazol which can be control vegetative growth and improve yield and fruit quality of Mit Ghamer peach trees.

6. MATERIALS AND METHODS Treatments: Spraying PLZ at 0 ppm (control).
The application was at approximately three weeks after full bloom

7. The following parameters were determined :
Shoot growth
Yield and Maturity
Fruit characteristics
Physical fruit characteristics
Chemical fruit characteristics
Leaf characteristics
Leaf area and dry weight %
Leaf nutrients

8. RESULTS
Shoot growth

9. Effect of different concentrations of paclobutrazol on shoot growth of peach trees (data are the mean of 2002 and 2003 seasons).
Shoot growth (cm)
Treatments
1 Oct.
15 Sept.
1 Sept.
15 Augs.
1 Augs.
15 July
1 July
15 June
1 June
15 May
1 May
15 April
1 April
15 March
68.33
57.07
48.00
48.43
42.57
38.57
67.00
56.73
47.77
67.33
55.83
47.00
48.33
42.37
38.20
65.67
54.90
46.33
42.23
37.67
64.00
57.17
45.00
47.50
41.73
36.93
63.17
52.27
44.33
47.17
41.40
36.67
61.50
52.00
43.50
46.67
40.90
36.00
59.67
51.17
43.00
45.33
40.57
35.00
57.67
41.33
43.67
40.07
33.67
55.67
45.07
40.00
42.67
32.80
51.33
44.07
39.83
40.60
36.17
30.43
46.17
39.70
31.17
27.33
33.17
28.33
29.57
25.37
23.70
17.67
17.83
17.73
15.70
15.07
14.50
Contrl
250 ppm
500 ppm
750 ppm
1000 ppm
1500 ppm
11.33
16.11
11.38
16.19
11.22
15.96
11.26
16.01
11.40
16.21
11.03
15.69
10.85
15.42
10.65
15.14
9.27
13.18
7.73
11.0
7.22
10.27
7.81
11.11
--- NS
L.S.D.at1%
L.S.D.at5%

10. Effect of paclobutrazol spray on shoot growth of peach trees

11. First picking before control (Days)
Effect of spraying Paclobutrazol on
yield and precocity of peach trees
during 2002 and 2003 seasons.
First picking before control (Days)
Yield (kg/tree)
Treatments
2003
2002 --
3.0
5.3
5.5
2.0
4.3
6.0
6.3
3.3
37.33
41.00
43.67
45.67
42.00
36.33
36.67
43.33
45.00
48.33
38.33
Control
250 ppm
500 ppm
750 ppm
1000 ppm
1500 ppm
3.83
5.44
4.12
5.86
L.S.D. at 5%
L.S.D. at 1%

12. Effect of spraying paclobutrazol on
physical fruit characteristics of peach
trees during 2003 and 2003 seasons.
Red skin color %
Firmness (kg/cm2)
Fruit length (cm)
Fruit diameter (cm)
Fruit volume (cm³)
Fruit weight (gms)
Treatments
2003
2002
38.33
50.00
64.00
71.67
70.67
45.67
40.67
49.33
67.33
76.00
44.67
4.09
5.00
5.27
4.37
5.37
4.97
4.49
4.78
4.38
5.51
5.08
5.53
6.13
6.02
5.67
5.82
5.63
6.09
6.20
5.89
6.03
5.47
5.77
5.93
5.88
5.69
5.90
6.39
5.79
6.07
90.67
102.33
107.67
118.33
97.67
103.00
94.67
104.67
109.33
123.33
98.67
110.00
94.33
105.33
114.00
121.67
103.33
110.67
96.67
115.33
127.33
106.67
113.33
Control
250 ppm
500 ppm
750 ppm
1000 ppm
1500 ppm
5.86
8.34
8.32
11.83
0.73 --
0.75 NS
0.28
---
0.26
0.36
0.18
4.39
6.24
7.14
10.16
5.11
7.26
8.90
12.66
L.S.D. at 5%
L.S.D. at 1%

13. Anthocyanin (optical density)
Effect of spraying Paclobutrazol on
chemical fruit characteristics of peach
trees during 2002 and 2003 seasons.
Acidity %
TSS %
Anthocyanin (optical density)
Treatments
2003
2002
1.206
1.021
1.070
1.071
0.960
0.855
1.224
0.947
1.114
0.891
0.835
10.03
11.07
10.70
11.30
12.13
10.07
10.13
11.27
10.87
11.57
12.33
10.33
0.130
0.184
0.192
0.200
0.209
0.159
0.120
0.181
0.190
0.210
0.225
0.150
Control
250 ppm
500 ppm
750 ppm
1000 ppm
1500 ppm
0.080
0.114
0.115
0.163
0.77
1.10
1.09
0.020
0.029
0.015
0.022
L.S.D. at 5%
L.S.D. at 1%

14. Effect of spraying Paclobutrazol on peach leaf characteristics and NPK
contents during 2002 and 2003 seasons. K% P% N%
Dry weight %
Leaf area (cm2)
Treatments
2003
2002
1.97
1.88
1.87
1.75
2.19
1.91
1.86
1.70
0.23
0.20
0.19
0.18
0.24
0.21
2.29
2.31
2.17
2.30
2.26
2.32
2.18
45.20
42.70
44.17
43.77
42.96
42.67
46.27
43.76
44.78
44.28
44.24
43.35
39.29
37.92
37.29
35.11
34.76
30.56
40.57
40.29
39.33
36.73
36.04
32.95
Control
250 ppm
500 ppm
750 ppm
1000 ppm
1500 ppm
0.07
---
0.25
0.03
0.04 NS
0.41
0.77
4.10
5.83
2.05
3.56
L.S.D. at 5%
L.S.D. at 1%

15. SUMMARY
Spraying paclobutrazol highly significant decreased shoot extension at all concentrations were used.
The highest concentration recorded the lowest values of shoot length during the two growing seasons.
The reduction in shoot growth rate before pit-hardening stage, resulted in obtaining larger fruits, with a consequent increase in yield and earlier fruit maturity .

16. SUMMARY
Spraying paclobutrazol at 750ppm achieved the highest values of yield/tree (48.33 and kg/tree) ,fruit weight ( and gms); volume ( and cm³); diameter (6.39 and 6.13 cm) and red skin color (76.00 and %), during the two seasons respectively.
Moreover, spraying pacloputrazol at all concentrations used increased fruit content of anthocyanin and TSS % but reduced acidity % in fruit juice in the two seasons of study.

17. SUMMARY
The results also showed that, leaf area and dry weight were reduced as a result of paclobutrazol spraying .
No clear effect on nitrogen leaf content was noticed, but phosphorus and potassium leaf content was decreased in paclobutrazol treatments in both seasons of study.

18. Conclusion & Recommendations
It could be concluded from this study that spraying Mit Ghamer peach
trees with paclobutrazol at 750 ppm was more effective in controlling
shoot growth, eliminating the need
for summer pruning, increasing
yield, advancing in fruit maturity
and improving fruit quality.
Conclusion & Recommendations

19. Bon appétit

20. Thanks for your attention!