الفهرس 
Material and methodsOnly 14 pages are availabe for public view
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Abstract
SUMMARY AND CONCLUSION
Experiments were carried out on a clay loam soil with pH 8.15 at the
Experimental Farm Station of the Faculty of Agriculture, Moshtohor-Kalubia
during the early summer seasons of 1993 and 1994. Field trails on tomato cv, UC
97-3 aimed to study the effect of N, P and S fertilization levels on plant growth,
chemical constituents, fruit yield and quality of tomato. Therefore, three separate
experiments were carried out as follows:
First Experiment: Effect of source and level of N-fertilizer on tomato.
This experiment included 12 treatments aimed to study the effect of
increasing N-Ievels ( 0, 60, 120, 180, 240 and 300 Kg N/fed. ) within two sources;
ammonium nitrate or urea on plant growth, chemical constituents, fruit yield and
fruit quality of tomato. Results showed that:
1- Vegetative growth:
Tomato plant growth especially fresh and dry weight were increased
with increasing N-Ievel up to 120 Kg N/fed. within urea or ammonium nitrate.
However, higher levels of N-application ( 240 or 300 Kg N/fed.) decreased plant
growth, as shown in both seasons. Late evaluation of plant growth at fruit setting
stage, also showed that adding 120 or 180 Kg N/fed. as ammonium nitrate
significantly increased tomato growth compared with other treatments.
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2- Mineral content of tomato plant foliage:
Results showed that N03-N, total -N and K-content in leaves and/or
branches were increased with adding ammonium nitrate as compared with urea,
when plants evaluated at flowering stage or at fruit setting stage of both seasons.
Regardless to N-form, Nand K uptake were increased significantly by increasing
level of N-application up to 120 Kg N/fed., but N03-N content was gradually and
significantly increased by increasing level of N-application up to 300 Kg N/fed.
Although P-uptake showed the same response at flowering stage but it was not
significantly affected by levels ofN-application, at fruit setting stage.
With respect to the interaction effect, data showed that N, P and K
uptake were not significantly affected by any treatment ofN-level x N-form, at
flowering stage, in both seasons. However, evaluation of N and K uptake of
foliage, at fruit setting stage showed that they were increased by increasing level of
N-application from 0 to 120-180 Kg N/fed. as urea or ammonium nitrate as a
general trend in both seasons. However, P-uptake ofleaves andlor branches was
not significantly affected by any of the interactinal treatments ofN-levels within
N-forms.
3- Tomato fruit yield :
Ammonium nitrate application gave the highest early, marketable and
,..
total yield of tomato fruit as compared with urea. Increasing N-level up to 60 Kg
N/fed. gave the highest early yield. however, increasing N-level up to 120 Kg
N/fed gave the highest marketable and total yield of tomato fruit. Higher levels of
N-application, 240 or 300 Kg NlFed. decreased early, marketable and total yield
production.
With respect to the interactional treatments, data showed that early,
mar] -table and total yield were not significantly affected by Nvsource within
N-Ie\e1 under such conditions of clay loam soil with pl I 8.15.
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4- Tomato fruit quality :
Ammonium nitrate application increased TSS % and N03-N content
of tomato fruit . Whereas, urea application significantly increased Vitamin-C
content and total acidity only in one season. as compared with ammonium nitrate.
Fruit dimensions were not significantly affected by N-source.
Concerning with the effect of Ndevels; increasing level of Napplication
from 0 up to 120 Kg NlFed. increased average fruit weight but fruit
shape was not significantly affected. Total acidity, TSS% and Vitamin-C content
were also increased by increasing N-Ievel up to 120 or 180 Kg N/Fed. Heavy Napplication
(240 and 300 Kg N/fed.) decreased average fruit weight and dry matter
% offruit. Whereas, N03-N content of tomato fruit was gradually and significantly
increased with increasing N-Ievel from 0 up to 300 Kg N/fed. This increase in
N03-N content was higher in fruits of plants supplied with ammonium nitrate than
with urea.
Conclusion
Ni-applicution at 120 Kg NIF ’ed:as ammonium nitrate is recommended to get the
best vegetative growth, mineral uptake, early, marketable and total yield with the
best tomato fruit quality. Heavy Ni-apptication at 240 or 300 Kg NlFed as urea
or ammonium nitrate is 1I0trecommended to avoid the decrease in plant growth,
yield and fruit quality.
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Second Experiment: Effect of S within P nutrition on tomato.
This experiment included 12 treatments, aimed to study the effect of
fertilization with three sulphur levels within four phosphorus levels on growth,
chemical constituents, yield and fruit quality of tomato. Elemental S- levels were 0,
150 and 300 Kg S/fed. and superphosphate levels were 0, 32, 64 and 96 Kg
PzOslfed. sulphur was added during soil preparation before transplanting.
Treatments were arranged in the field using split plot design; S-Ievels surved as
main plots and P- levels were randomly distributed as sub-plots. The obtained
results were as follows:
1- Vegetative growth:
Data of plant growth at flowering or fruit setting stage showed that
fresh and dry weight of leaves or branches were significantly increased with
increasing level of S-application up to 150 or 300 Kg S/fed. With respect to
P-fertilizer levels, 32 or 64 Kg P20slfed. gave the best plant growth, especially for
fresh and dry weight as compared with the higher or lower used P-Ievels. Therefore
the highest value offresh and dry weight were recorded with application of 32 or
~4 Kg P20sifed within 300 Kg S/fed. followed by the application of 150 Kg S/fed
+ 64 Kg P20slfed. but the lowest value were recorded with the control.
It was clear that S-application at high or moderate levels; 300 or 150 Kg S/fed.
could save P-fertilizer and reduce the applied level of P-required to get the same
effect on plant growth, Generally, J50 Kg S equal 10 save 200 Kg of
superphosphate (32 Kg P205ljed) .
4- Tomato fruit quality:
Results showed that fruit dimensions, average fruit weight, TSS %
and Vitamin-C content were not significantly affected by S-application. Fruit dry
matter % and total acidity were gradually increased with increasing S-application
only in one season.
As for the effect of P-appli cati on, data showed that fruit dimensions
and TSS % were not significantly affected by increasing P-application levels in
both seasons. However, fruit dry matter % and average fruit weight were
significantly increased by increasing level of P-fertilizer up to 96 Kg P20s/fed. On
the other hand, fruit acidity and Vitamin-C content were decreased by increasing
level of P-application only in one season.
With respect to the effect of sulphur within phosphorus, data showed
that fruit dimensions, TSS % and average fruit weight were not significantly
affected by these interactional treatments in both seasons, but fruit dry matter %
was increased by increasing P-application up to 96 Kg P20s/fed within all level of
S-application up to 150 or 300 Kg S/fed. within all level of P-application .
Conclusion
64 Kg P205 within 150 Kgof elemental S/fed is recommended to get the best
growth, mineral content and the highest early, marketable and total yield with
goodfruit quality.
Third Experiment: Effect of P within N application on tomato.
This experiment included 20 treatments, aimed to study the effect of
increasing N-levels (0, 120, 180, 240 and 300 Kg N/fed.) within P-Ievels (0, 64, 80
and 96 Kg P20s/fed.) on plant growth, fruit yield and fruit quality of tomato.
Experimental design was randomized block design. Results were as follows:
1· Vegetative growth:
Tomato plant growth, fresh and dry weight were increased by
increasing levels of N-application up to 120 or 180 Kg N/fed. Moreover, tomato
plant growth was increased by increasing level of P-application up to 64 Kg
PzOs/fed. Whereas, heavy application of nitrogen at 240 or 300 Kg N/fed. or
phosphorus at 96 Kg P20s/fed. decreased plant growth.
With respect to interactional treatments, data showed that increasing
N-levels within P-levels had no significant effect on tomato plant growth evaluated
at flowering or fruit setting stage.
2.Tomato fruit yield and its components:
With respect to N-fertilizer, data showed that 120 Kg N/fed was the
best level to get the highest early, marketable and total yield. However, heavy
”t-l-application up to 240 or 300 Kg N/fed. decreased early, marketable and total
yield of tomato. As for Pvfertilizer, data showed that 64 Kg PzOs/fed. gave the
highest early, marketable and total yield. Moreover, heavy P-application at 80 or
96 Kg PzOs/fed. did not increase either early, marketable or total yield. Concerning
the interactional treatments, data showed that 120 Kg N + 64 Kg PzOs/fed. was the
best level of nitrogen within phosphorus to get the highest early, marketable and
tot~l ”lplr1 of tomato fruit • - ••..
3- Tomato fruit quality:
With respect to N-fertilizer, data showed that fruit dimension, fruit
dry matter % and TSS % were not significantly affected by increasing level of
N-application. However, average fruit weight, Vitamin-C and total acidity were
increased by increasing level of N-application up to 180 Kg N/fed. N03-N
accumulation was gradually and significantly increased by increasing level of
N-application from 0 up to 300 Kg N/fed. With respect to P-fertilizer, data showed
that fruit dimension, average fruit weight, fruit dry matter % , TSS %and Vitamin-
C content were not significantly affected by increasing level of P-application
.However, total acidity was significantly increased by increasing level of
P-application up to 64 Kg PzOs/fed. N03-N accumulation decreased gradually and
significantly by increasing level of P-application.
With respect to nitrogen within phosphorus fertilization, data showed
that fruit dimension, average fruit weight and fruit dry matter % were not
significantly affected by any of the used interactional treatments ofN within P.
However, all treatments of N x P improved Vitamin-C content and TSS % of
tomato juice as compared with the control. Total acidity were increased by adding
180 Kg N + 64 Kg PzOs/fed. Nitrate accumulation in fruits was gradually increased
with increasing level ofN-application within all levels of P-application.
General conclusion for all trials
As for tomato cv. UC-97-3 grown ill the early summer season
under open field conditions of clay loam soil witlt pH 8.15, adding 120 Kg
NIJed. as ammonium nitrate + 64 Kg P205/fed. +150 Kg Slfed.is
recommended to get the best growth, mineral uptake associated with tlte
highest early, marketable and totalfruit yield with high fruit quality with a
lowering nitrate accumulation in tomato fruits.