الفهرس 
INDRODUCTION
Physical characteristicsOnly 14 pages are availabe for public view
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Abstract
This investigation was carried out throughout 2012 and 2013 seasons at the experimental orchard, Faculty of Agriculture, Assiut University. Twelve trees uniformly in vigor (4 treatments x 3 replication) of each Abbodi and Abiad Aswan fig cvs. were selected for this study. The chosen trees were planted in clay soil, and received the same horticultural managements.
This experiment aimed to study the rules and the effects of gibberellic acid (GA3), benzyl amino-purine (BA), and naphthalene acetic acid (NAA) on the developmental changes of some physical and chemical and endogenous hormones properties as well as fruit ripening of Abbodi and Abiad Aswan fig fruits during its growth.
The plant growth regulators (PGRs) were sprayed on June 30th for both cultivars when the fruits reached six weeks old and their size were about 1.55 -1.69 cm based on the following treatments:
- Control (only spraying with distilled water)
- Spraying with 50 ppm of GA3
- Spraying with 40 ppm of BA
- Spraying with 25 ppm of NAA
Some physical characteristics and growth of fruits (such as fruit diameter, weight and volume), fruit maturation, and chemical characteristics (such as TSS, acidity and reducing sugars) were determined as affected by the spraying by PGRs.
The endogenous gibberellins, auxins and cytokinins were also measured in the fruits of Abbodi cv. after spraying with the GA3, NAA and BA growth regulators.
Results of this investigation could be summarized as follows:
A-Fruit growth and its physical characteristics:
1- Abbodi and Abiad Aswan fig fruits took approximately similar trend as response to growth regulators application in both experimental seasons.
2- The growth curve of fig fruits as measured by fruit diameter showed three different periods of growth (I, II and III). During the first growth period (I) the rate of diameter increasment was very rapid and took about five weeks in Abbodi and Abiad Aswan fig cvs., followed by the second growth period (II), which had slow rate of diameter increasing and took four weeks in the two cultivars, whereas the third period (III) had more rapid increasing rate in diameter growth till the fruits reached the maturity and took seven weeks in untreated fruits (control) of Abbodi and Abiad Aswan fig cultivars.
3- The fruit weight and volume of both cultivars took approximately the same trend as diameter concerning the response of applied growth regulators during both studied seasons.
4- The effect of applied growth regulators on diameter, weight and volume of fig fruits, cleared that GA3 and NAA significantly increased these characteristics as compared with BA treatment and untreated fruits during all developmental stages.
Moreover, the treated fruits with the three growth regulators were significantly smaller comparing with untreated one at the maturity stage in both experimental seasons 2012 and 2013.
5- GA3 treatment advanced fruit maturity by 4 weeks, on Abiad Aswan and 3 weeks on Abbodi cv. while NAA enhanced fruit maturity of Abiad Aswan cv. by 3 weeks and one week for Abbodi cv. earlier than the control. In addition BA advanced fruit maturity by 2 weeks for Abiad Aswan cv. and one week for Abbodi cv. during the two experimental seasons.
B-Chemical characteristics of fruits:
1- The result indicated that GA3, NAA and BA significantly increased the fruit content of TSS as compared with untreated fruits (control) during all periods of fruit growth until maturity. At the maturity stage the untreated fruits (control) had the highest values of TSS percentages comparing with all PGRs treatments during the both experimental seasons for both cultivars.
2- The result could be demonstrated that the average values of acidity content in fig fruits gradually and significantly inceased during the second growth period until the earlier weeks of the third period, then the acidity content gradually decreased and reached the lowest values at the ripe stage of both cultivars during 2012 and 2013 seasons.
GA3, NAA and BA significantly increased the fruit content of total acidity during stage II and earlier weeks of stage III as compared with untreated fruits (control). This could be due to the enhancing of ripening process.
3- The result indicated that treatment means of total soluble solids / acid ratio gradually and significantly decreased duing the second growth period then it increased significantly until maturity in both cvs. and experimental seasons.
The increment of TSS / acid ratio in untreated fruits due to the increasing of TSS and decreasing of acidity % in these fruits comparing with all other treatments.
4- The data show that the percentage of reducing sugar significantlly increased by advancing the fruit age and reached its maximum values at maturity stage of both cultivars under all treatments during 2012 and 2013 seasons.
On the other hand, the applied growth regulators GA3, NAA and BA significantly increased the reducing sugars content during all tested growth period of fruits as compared with untreated fruits in both experimental seasons.
Moreover, at maturity stage the untreated fruit (control) contained the highest values of reducing sugars % comparing with other treatments during both studied seasons.
5- The effect of applied PGRS on the endogenous hormones contents:
A: The external spraying with GA3 significantly increased the endogenous contents of GAS in Abbodi fig fruits which still higher than in untreated fruits (control) until maturity stage.
B: The changes in endogenous auxin content in Abbodi fig fruits after spraying with NAA took similar trend as GAS content. It was higher in the treated fruits than those untreated one and reached its maximum value after 2 weeks from spraying date. Then it decreased gradually until maturity.
C: Spraying with BA significantly increased the endogenous cytokinins in Abbodi fruits compared with untreated fruits (control). Similar tendency was found concerning the changes in cytokinins contents as gibberellins and auxins in the tested sampels.
Recommendation:
It could be recommended that the application of some growth regulators such as GA3, NAA and BA enhance the fruit maturity of Abbodi and Abiad Aswan fig fruits by about 1 – 4 weeks. The spraying with GA3 (at 50 ppm) is more effective than NAA and BA on enhancing the maturity of these fruits without any adverse on fruit quality.