الفهرس 
IntroductionOnly 14 pages are availabe for public view
 |  | from | 116 |  |  |
| | | from | 116 | | |
Abstract
- 84 -
SUMMARY
Three field experiments were carried out during 1984/85,
1985/86 and 1986/87 seasons at the Experimental Field of Shandaweel
Research Station, Sohag Governorate. The aim of the experiments
was to study the effect of wheat varieties and fertilization on wheat
yield and aphids infestation.
The soil of the experiments was clay textured with a pH
of 8.0, an organic matter content between 0.77 - 1.93 % and contained
31 ppm Nand 8.5 ppm available P.
Each experiment included 20 treatments which were the
combination of two varieties and ten fertilization treatments. Factor
under study were :
A. Varieties: Sakha 69 and Stork.
B. Fertilization:
a. Without - N + 15 kg P 205 + 24 kg K20/fed.
b. 15 kg N + 15 kg P205 + 24 kg K{)/fed.
c. 30 kg N + 15 kg P205 + 24 kg KiO/fed•
d. 45 kg N + 15 kg P 20 5 + 24 kg K20/fed.
e. 60 kg N + 15 kg P205 + 24 kg K20/fed.
f. 75 kg N + 15 kg; P205 + 24 kg K20/fed.
g. 90 kg N + 15 kg; P205 + 24 kg K20/fed.
h. 75 kg N + without - P 205 + 24 kg K20!ted.
r, 75 kg N + 30 kg P 205 + 24 kg K20/fed.
J. 75 kg N + 15 kg P20 + without - K20.
- 85-
The design of the experiments was a split-plot with four
replication. The two varieties were arranged at random in the main
plots and the sub-plots were assigned to fertilizer treatments.
Results could be summarized as foHows :
1. Population densities of aphid per wheat plant varies
with the stage of the plant, season, species and also with other factors
Rhopalosiphum padi was the predominant species accounting for 60.93%
of the aphids population. Meanwhile, Schizaphis graminum and Rhopalosiphum
maidis accounted for 36.27 % and 2.751 %, respectively in Shandaweel
conditions.
Stork variety had higher number of B.: padi and s. graminum
than Sakha 69 in the first season only, while the differences between
two varieties failed to reach the level of significant.
The infestation of wheat plants by three species were significantly
increased by increasing N levels up to 90 kg/fed. at different
growth stages, namely, 70, 90 and 110 days from sowing in the both
seasons. Whereas, the infestation were lower under without P-fertlllzer
and application of 30 kg P20/fed. compared with 15 kg P20/fed•
in one season only. On the other hand, K-fertilizer had no significant
effect on aphid population in the both seasons.
2. Stork variety was earlier in heading than Sakha 69.
This result was statistically evidenced in one season.
Wheat plants showed out spikes later as the nitrogen level
increased up to the level of 90 kg/fed. in the three seasons as well
- 86 -
as in combined data. On the other hand, application either P or K
showed no significant effect on the heading date of wheat plants
in the three successive seasons.
The effect of the interaction on the heading date was not
significant in the three successive seasons.
3. Wheat varieties exerted a marked effect on maturing
date in the three seasons. Stork had shortest period to maturity than
Sakha 69.
Fertilization treatments showed significant effect on the
number of days from sowing to maturity. Application of 90 kg N/fed.
to wheat plants prolonged the period to maturing 10.25, 9.27 and
3.88 days as compared without N-application in the first, second and
third seasons, respectively. But, application of P and K had no significant
effect on maturing date of wheat plants.
The effect of the interaction on maturing date was significant
in 1985/86 season only. Stork variety carne to maturity early when
it fertilized by 15 kg PZ05 +24kg K20/fed. (w itbout-N), while Sakha
69 came to maturity lately when it fertilized by higher levels of
N (90 kg/fed.).
4. Plant height of two wheat varieties were significantly
different in the three seasons as well as combined data. Sakha 69
variety produced higher plants than Stork.
Nitrogen showed significant influence on the height of wheat
- 87 -
plants in the three seasons. The plant height significantly increased
with increasing N-Ievel up to 60 kg/fed. On the other hand, application
neither P nor K fertilizers had any significant effect on wheat plant
height in the three successive seasons.
The effect of the interaction on the plant height of wheat
plants was not significant in the three seasons.
5. Wheat varieties exhibited significant effect on spike
length in the three successive seasons. Sakha 69 produced significantly
longer spike than variety of Stork.
Increasing N-Ievel tended to increase spike length up to
45 kg/fed. in the three seasons. On t~e contrary, application of P
and K had no significant effect on spike length.
The effect of the interaction on the spike length was significant
in 1984/85, 1985/86 and combined data. Variety of Sakha 69 was
more response to nitrogen fertilizrs than Stork variety.
6. Wheat varieties showed significant effect on the number
of spikes/rn” in the first season only. In this season, Sakha 69 had
higher number of spikes/rn! than Stork with significant differences.
The number of spikes/rn ’ significantly increased with increasing
N, P and K levels in the three successive seasons. Combined analysis
showed that the highest number of spikes/rn ’ produced from application
of 75 kg N + 30 kg P205 + 24 kg K20/fed. While, the lowest average
produced with 15 kg P20 5 + 2ft kg K20!fed.
._--_._--
- 88 -
The effect of the interaction was not significant in the three
seasons. While, combined data show that the number of spikes/rn?
was significantly affected with the interaction. Number of spikes/rn”
was significantly increased with N increased up 60 kg/fed. for Sakha
69 and up to 90 kg/fed. for Stork.
7. The differences among two varieties in number of spikelets
/ spike were significantly confirmed in the three seasons as well as
combined data. Variety of Sakha 69 had greater number of spikelets/
spike compared with Stork variety.
Number of spikelets/spike significantly increased by nitrogen
fertilization up to 60 kg/fed. Further addition of N did not result
in further significant increase in the three seasons. On the other hand,
application of P or K had no significant effect on number of spike lets/
spike.
The effect of the interaction was significant on the number
of spikelets/ m2 in the first season only.
8. Wheat varieties had no significant effect on the number
of grains/spike in the three successive seasons.
Number of grains/spike increased constantly as the nitrogen
level increased up to 90 kg/fed., without significant differences between
60, 75 and 90’ kg/fed. Nevertheless, application of P or K had no
significant effect on the previous character in the three seasons.
The effect of the interaction between varieties and fertilizers
- 89 -
on the number of grains/spike was not significant m the three seasons.
9. Grains weight of 10-spike was affected by varietial
characteristics in the three successive seasons. Variety of Stork produced
heavier of 10 spikes than Sakha 69 variety.
Weight of grams of 10 spikes increased by increasing N level
up to 90 kg/fed. in the three successive seasons.
Grains weight of 10 spikes had no significantly affected
with the interaction between varieties and fertilizer treatments in
the three successive seasons.
10. In the three seasons, varieties had significant effect
on the weight of 1000-grain. Variety of Stork produced heavier grains
than Sakha 69.
The effect of fertilizer treatments on 1000 grain weight
showed seasonal variation. In 1985/86 and 1986/87 seasons, weight
of 1000 grains significantly increased with application of N up to
30 kg/fed. While, in 1984/85 as well as combined data weight of
1000-grain was not significantly affected with fertilizer treatments.
Whereas, addition of P or K did not show any significant increase
on the 1000-grain weight in the three seasons.
The effect of the interaction between wheat varieties and
fertilizer treatments on the weight of 1000 grain was not significant
in the three successive seasons.
-~~_._-~----- ~----_._--
- 90 -
11. Wheat varieties showed seasonal difference in their
effect on the yield on grain. Only in one season the effect was significant,
where Stork was superior to other variety in affecting the grain
yield of wheat. The relative yields were 100 and 97 %, 100 and 109%
and 100 and 108 % in 1984/85, 1985/86 and 1986/87 seasons, respectively.
The grain yield of wheat was greatly influenced by application
of nitrogen fertilizers. Grain yield increased consistently with each
rate of N up to 75 kg/fed. in 1984/85 and up to 90 kg N/fed. in the
other two seasons. Application of 75 kg N/ fed. significantly increased
the grain yield relatively over the control treatment (without-N)
by 288, 119 and 220 % in the three successive seasons.
The interaction effect between varieties and fertilizer treatments
on the grain yield/fed. was significant in one season only.
Stork variety was more response to N-fertilizer than Sakha 69.
12. Sakha 69 variety revaled a significant superiority in straw
yield compared with wheat variety Stork in 1984/85 and 1985/86
seasons.
The straw yield significantly ilncreased as N-level increased
till the rate of 60 kg/fed. The average straw yield in the three seasons
showed that nitrogen increased the straw yield by 167, 184 and 195%
over the control (without N fertilizer) as it was applied of rates
of 60, 70 and 90 kg/fed., respectively. On the other hand, application
of P and K had no significant effect on the straw yield/fed. in all
- 91 -
the seasons.
The effect of the interaction between varieties and fertilizers
on the straw yield was not significant in the three seasons.
13. Both varieties were similar in their potential for protein
synthesis inthe three successive seasons.
Crude protein content of grains as percentage was not affected
by the addition of nitrogen. Similarly, neither P nor K had effect
on protein content.