الفهرس 
Material and methodsOnly 14 pages are availabe for public view
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Abstract
This study was conducted during the two seasons of 1993 and
1994, on twenty years old Washington navel orange trees budded on
sour orange rootstock grown at three locations i.e. Wady EI-Mollak
(EI-Esmailia governorate); South EI-Tahreer and El-Qanater (El-
Qaliobia governorate).
Twenty trees, healthy and nearly similar in vigor received the
common fertilization and irrigation programs used in each location,
were chosen.
The present study included two parts: The first part was fruit
maturity determination, while the second was fruit handling and
storage treatments.
Anyhow, fruit maturity study covered the effect of orchard
location (heat units) and irrigation system.
In this respect, fruit samples were collected from labeled fruits
at the three locations starting from the age of 150 days from fruit set,
and repeated every 10 days interval till the age of 200 days. Each fruit
sample comprised 30 fruits for determining maturity indices, i.e. total
soluble solids, acidity, and T.S.S/acid ratio. Meanwhile, available heat
units at each location for different fruit ages were calculated. At each
date, 25 fruits per each sample were stored under room temperature
(l8±40C) for studying the ability of harvested fruits to maintain their
fine conditions without shrinkage.
Furthermore, fruit handling and storage study included the
effect of orchard location, irrigation system, storage method, package
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SIze, storage temperature, and fungicides and non-traditional
treatments on fruit storage.
Mature fruits were harvested from trees grown at Wady El-
Mollak location under drip irrigation for studying the effect of storage
temperature and package size, while for studying the effect of location
and irrigation system on fruit storage, fruits were taken from the
different three locations as well as Wady EI-Mollak location,
respectively.
Fruits were soaked in water containing 1500ppm SOPP at 45°C
and pH 11.8 for four minutes, dried and sprayed with wax containing
4000 ppm TBZ.
The treated fruits were packed in export packages for studying
the effect of storage temperatures, i.e. room (18±4°C), 4±I°C and
7±I0C besides the effect of different locations under study and
different irrigation systems at Wady EI-Mollak on the shelflife of
fruits.
Furthermore, for studying the effect of package size i.e.
consumer and export package, fruits were taken from Wady El- .
Mollak location under drip irrigation. Meanwhile, fruits were also
harvested from El-Qanater location for studying the effect of
fungicides and non-traditional treatments on fruit storage. In this
respect, fruits were washed with tap water, dried then treated as
follows:
1-Control (untreated): Clean dry fruits were sprayed with wax.
2- 1500 ppm SOPP (Sodium orthophenylphenate) dissolved in water
at 45°C for 4 minutes. Fruits left to dry then sprayed with wax.
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3- 2000 ppm IMZ (Imazolil): Clean dry fruits were sprayed with wax
containing 2000 ppm IMZ.
4- 4000 ppm TBZ (Thiobendazole): Clean dry fruits were sprayed
with wax containing 4000 ppm TBZ.
5- Hot water treatment at 47°C for 6 minutes.
6- 500 ppm Garlic oil: Clean dry fruits were sprayed with wax
containing 150 ppm Pro-Gib plus.
All treated fruits were packed in export package and stored
under both room temperature (18±4°C) and 7±1°C. Fruit samples
were taken every 20 days till the end of storage period.
Generally, in all previous experiments, fruits were subjected to
the following determinations of fruit quality during storage: fruit
decay, fruit weight loss and fruit analysis i.e. TSS, acidity, TSS: acid
ratio and ascorbic acid contents.
The obtained results can be summarized as follow:
Part I: Fruit Maturity:
1- Fruits ofEl- Tahrir location attained maturity when they were 170-
175 days old (20 - 30 September), received heat units 14945,
total soluble solids 9.3%, total acidity 1.09”10 and total soluble
solids: acid ratio 8.52: 1. While, fruits from EI-Qanater location
reached maturity when they were 160 to 180 days old (10 - 20
September) received heat units 1586.8 with total soluble solids
(9.5 - 10.4%), total acidity (1.09 to 1.25%), TSS: acid ratio (8.51:
1). On the other hand, at Wady El-Mollak location fruits became
mature at the age of 175-180 days (1- 10 October), heat units
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(1534 - 1605), total soluble solids (9.2 - 9.5%), total acidity
(0.98 - 1.26%), total soluble solids: acid ratio (7.50 - 9.39 : 1).
Meanwhile, Wady El-Mollak location under drip irrigation
system, fruits reached maturity when their age was 160 - 165
days (10 - 20 September), heat units (1352.5 - 1489.0) with fruit
total soluble solids 10.5%, total acidity (1.15 - 1.31%), total
soluble solids: acid ratio (8.10 - 9.13 : 1).
2- Fruits harvested before or after the above indicated ages at each of
the indicated locations or irrigation systems were not best suited
for long shipment as they showed shrinkage when kept under
room temperature for different periods less than 25 days after
harvest.
3- Total soluble solids percentage increased until the age of 190 days
from fruit set in all locations under study.
4- Fruits from El-Qanater location, generally, showed higher fruit total
soluble solids percentages as compared with the other two
locations used.
5- Trees irrigated with surface irrigation at Wady El-Mollak location .
gave fruits with lower values of juice TSS content until 180 days
from fruit set as compared with the corresponding ones under
drip irrigation system.
6- Titmtable acidity of Navel fruit juice decreased towards the age of
200 days in all locations.
7- No significant differences were obtained between various locations
under study in fruit juice acidity.
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8- Under the two irrigation systems at Wady El-Mollak location,
titratable juice acidity decreased as fruits approached maturity.
However, irrigation systems had no effect on fruit juice acidity.
9- TSS: acid ratio in fruit juice of Navel orange increased with the
progress in fruit age in all locations under study.
10- Both El-Tahrir and Wady El-Mollak locations gave fruits with
higher values of TSS : acid ratio as compared with El-Qanater
location.
11- TSS : acid ratio in fruit juice increased with increasing fruit age
under both irrigation systems used.
12- Fruits produced under drip irrigation system had higher TSS : acid
ratio as compared with the corresponding ones of those of surface
irrigation system.
Part 2: Post-harvest (Fruit storage):
1- Storage method:
1- Effect of orchard location and irrigation system:
1- Fruit decay percentages were directly proportional and coincided .
with the increase in storage duration under different storage
methods and different orchard locations. Room temperature
storage induced higher rate of fruit decay than those of cold
storage. In this sphere, fruit decay percentage increased with
prolonged storage period up to 120 days under cold storage, while
fruits stored at room temperature became unacceptable for
consumption after 60 days. Besides, El-Tahrir location showed
lower fruit decay percentage followed by Wady El-Mollak as
compared with EI-Qanater location. In addition, fruit decay
percentage of trees under drip irrigation system gave lower values
as compared with those for trees under surface irrigation.
2- Fruit weight loss percentage increased with prolonging the storage
period in all locations and storage methods. Fruits stored under
cold temperature had the lowest weight loss percentage than those
stored at room temperature. Fruit weight loss percentage increased
with the extension of storage period up to 120 days when fruits
stored under cold storage, while fruits at room temperature became
unacceptable to consumer after 60 days. Moreover, EI-Tahrir
location caused the lowest fiuit weight loss percentage followed
by EI-Qanater location as compared with Wady EI-Mollak
location. Besides, fruit weight loss percentage from trees under
drip irrigation system gave the lowest values as compared with
those under surface irrigation system.
3- During the storage period that was extended to 90 days, fiuits juice
TSS increased gradually whether fiuits were stored under cold or
room temperature. Room temperature gave lower rate of increase .
in fiuit TSS than those under cold storage. In addition, juice TSS%
was the highest in fiuits obtained from El-Qanater and Wady EIMollak,
while fiuits of EI-Tahrir were the lowest in juice TSS%
content. Also, TSS% of fiuits from trees under drip irrigation
system gave higher values as compared with those fiuits from
trees under surface irrigation.
4- Fruit acidity decreased gradually by extending the period of storage
whether fiuits stored under room or cold storage. In this concern,
cold storage induced higher rate of DROP in fruit acidity than those
under room temperature storage. Fruit juice acidity varied
according to orchard location. Nevertheless, fruit acidity was
highest in fruits obtained from EI-Qanater followed by Wady EIMollak
as compared with EI-Tahrir location. At Wady EI-Mollak
location fruits picked from trees under drip irrigation had highest
juice acidity content than those harvested from trees under surface
irrigation.
5- During storage period that extended up to 90 days TSS:acid ratio
increased gradually whether fruits were stored under cold or room
temperature. TSS:acid ratio in fruit juice at maturity varied
according to orchard location. However, fruits of EI-Tahrir
location had the highest value of TSS:acid ratio, while both EIQanater
and Wady El-Mollak locations had nearly similar values.
At Wady EI-Mollak location no significant difference was
obtained between fruits picked from trees under drip irrigation and
those under surface irrigation.
6- Ascorbic acid content in fruit juice decreased by the advance in .
storage period. The DROP in ascorbic acid content during storage
was at a higher rate in fruits under room storage than those under
cold storage. At picking time, ascorbic acid content was higher in
fruits obtained from EI-Qanater followed by those from Wady EIMollak
and EI-Tahrir locations. Fruits harvested from trees under
drip irrigation had higher juice ascorbic acid content than those
picked from trees under surface irrigation.
II-Package size:
1- Decay percentage is directly proportional and coincided with the
increase in storage duration in all different packages used i.e.
export package and consumer package. Moreover, consumer
package, reduced fruit decay percentage in relation to export
package.
2- Fruit weight loss percentage of export and consumer packages
increased with increasing storage period. Consumer package
reduced weight loss percentage as compared with export size
package.
3- Data clearly indicate that fruit juice TSS increased gradually during
the storage period. Moreover, packages size had no significant
effect on fruit total soluble solids.
4- Fruit juice acidity decreased gradually with prolonging storage
period. No significant difference was obtained between export and
consumer packages in this respect.
5- TSS : acid ratio in fruit juice increased with increasing storage
period for either export or consumer packages used. No significant .
difference was noticed between export and consumer packages.
6- Fruit ascorbic acid content decreased with prolonged storage. No
significant difference was evident between the two package sizes
used.
111-Storage temperature:
1- Fruit decay percentage increased with prolonging storage period.
Decay percentage of fruits stored under room temperature
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(l8±40C) had the highest percentage followed by fruits stored at
7±1°C and 4±1°C in a descending order.
2- Fruit weight loss is directly proportional and coincided with the
increase in storage duration in all storage temperatures used. Fruits
stored at 4±1°C had significantly the lowest weight loss followed
by fruits stored at 7±lOC as compared with fruits stored under
room temperature. In the same time, fruit weight loss percentage
increased with the progress in storage period up to 90 days when
fruits stored at 4±1°C and 7±1”C. Fruit weight loss percentage was
much higher under room temperature and became unacceptable to
consumers after 60 days.
3- Fruit juice TSS content increased with advancing storage period.
The lowest temperature 4±1°C induced the highest increase in fruit
TSS percentage during storage as compared with the other two
temperatures used. No significance was detected between 4±1°C
and 7± 1°C in this respect.
4- Data indicate that in all storage temperatures used the percentage of
fruit juice acidity decreased with the increase in the storage period. .
No significant differences were obtained between juice acidity of
fruits stored at 7±1°C and 4±1°C but, was significant between
fruits stored at room temperature and fruits stored at 4±1”C.
5- TSS: acid ratio increased by increasing storage period in all storage
temperatures. Fruits stored at 4±1°C produced the highest ratio of
TSS : acid followed by fruits stored at 7±1 as compared with fruits
stored under room temperature in a descending order.
6- Fruit juice ascorbic acid content decreased gradually as storage
period increased in all storage temperatures used. Storage under
low temperature (4±I°C) reduced the loss in fruit juice ascorbic
acid content.
IV- Fungicides and the non-traditional treatments:
1- Fruit decay percentage increased with the extension of fruit storage
period for all different temperatures of storage. Fruits kept at room
temperature became unacceptable to consumers after 80 days for
the control treatment, while the decay percentages for other
treatments ranged between 15 and 39% after the same period. All
fruits kept at room temperature decayed after 100 days for all
treatments. Fruits stored at 7±1°C didn’t show any decay up to 80
days of cold storage when treated with Garlic oil. Pro-Gib, IMZ,
and TBZ treatments succeeded in maintaining all fruits without
decay for 40 days, while hot water and SOPP treatments had 3.0%
fruit decay and control fruits had 36% fruit decay after the same
period of cold storage. Garlic oil as a non-traditional treatment
succeeded in reducing fruit decay under cold storage up to 12% for
160 days storage and between 18 to 39% for other fungicides and
non-traditional treatments. Untreated fruits (control) were
completely unacceptable to consumers after 100 days of cold
storage. Anyhow, treating fruits with Garlic oil then storage at
7±I°C gave the least percentage offruit decay even after 160 days
of cold storage. SOPP fungicide was the second best, while hot
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water and Pro-Gib-plus treatments had the highest percentages of
fruit decay. The TBZ and IMZ fungicide treatments were. in
between.
2- Prolonging the storage period resulted in increased fruit weight
loss. After 80 days storage at room temperature, fruits treated with
fungicides ranged between 15.9% for IMZ treatment to 17.9% for
SOPP treatment. Fruits received non-traditional treatments lost
between 21.0% for Garlic oil treatment and 24.9% for hot water
treatment for their weight after the same period of room
temperature storage. After 80 days of room temperature storage all
fruits became unacceptable to consumers, while fruits stored at
7±loC and 85% RH remained acceptable to consumers for more
than 120 days. Weight loss for control fruits after 120 days of cold
storage was only 10.5%, for fungicide treatments ranged between
7.0 for IMZ and 7.7% for SOPP and for the non-traditional
treatments ranged between 7.1% for Garlic oil and 9.2% for hot
water treatments. Fruits treated with Garlic oil or with IMZ
remained acceptable to consumers up to 160 days of cold storage
with fruit weight loss of 9.4% for Garlic oil and 12.1% for IMZ
treatments.
3- TSS percentage, of all treatments used, increased with prolonging
period of fruit storage. Fruits of the control became unacceptable
to the consumers after 60 days of storage under room temperature
and 80 days under cold storage. Fruits treated with Garlic oil or
chemical fungicides were acceptable to the consumers up to the
end of cold storag , while Pro-Gib plus, and hot water as nontraditional
treatmen failed in realizing such success.
4- Fruit juice acidity un er different treatments decreased with storage
either under room r cold temperatures under the same storage
method. The differ nee between either fungicide treatments or
non-traditional trean ents was not clearly noticed.
5- TSS : acid ratio in fruit juice increased with increasing storage
period. Fruits treat with Garlic oil had lowest values ofTSS :
acid ratio in comparrson with fungicide treatments i.e. SOPP, IMZ
and TBZ which had nearly similar values at 160 days storage.
6- Juice ascorbic acid content of different treatments decreased with
increasing the period of storage. At 100 days of cold storage, fruits
treated with hot water were inferior in ascorbic acid content as
compared with other treatments. At the end of cold storage (160
days), fruits treated with Garlic oil surpassed fungicides in fruit
ascorbic acid content.