الفهرس 
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Abstract
The present study was carried out at the Agricultural Research and
Experiment center of the Faculty of Agriculture at Moshtohor, Zagazig
University, Kalubia Governorate, Egypt during 1993 and 1995 seasons. The
aims of this study were to determine the effect of weed control, tillage
systems and their interaction on total annual weed, growth, yield and Yield
components and grain chemical contents. The tillage systems used in this
study were as follows:
1. No-tillage
2. Chisel plowing (once): before the sowing.
3. Chisel plowing (twice): before sowing with one-day interval in
between.
4. Chisel plowing (twice): before sowing with a week interval in between.
The chemical and mechanical weed control treatments used in this study
were as follows:
1. Unweeded (check).
2. Hand hoeing (once) was done immediately before first irrigation.
3. Hand hoeing (once) was done a week before first irrigation.
4. Hand hoeing (twice), the first was done immediately before first
irrigation and the second immediately before the second irrigation.
5. Hand hoeing (twice) which the first was done a week before first
irrigation and the second one was done immediately before the second
irrigation.
6. Hand weeding (once) was done immediately before first irrigation.
7. Hand weeding (twice), the first was done immediately before first
irrigation and the second one right before the second irrigation.
8. Atrazine (Gessaprim 80% w.p.): (2-chloro-4-ethylamino-6-isopropyl
amino-I, 3, 5 triazine) which applied after sowing as pre-emergence
application at rate of O.75 kg/fed.
9. Atrazine at 0.75 kg/fed and hand hoeing once was done immediately
before the second irrigation.
The experimental design was a split plot with four replications. Tillage
systems were assigned at random in the main plots. Whereas, chemical and
mechanical weed control treatments were randomly arranged in the subplots.
Each plot consisted of five ridges 5 ill long and 70 em apart.
The preceding winter crop was barseem in both seasons. Maize (Hybrid
310) was sown on 27 and 19 June in 1993 and 19954 seasons, respectively.
The following data were recorded:
1. Soil characteristics
a. soil bulk density
b. soil porosity
2. Weed survey 45 and 75 days from sowing:
a. number of weeds/nr’
b. fresh weight of weeds/m’
c. dry weight of weeds/nr’
3. Maize characteristics
a. growth characters 60 and 90 days from sowing
1. plant height
2. dry weight of leaves/plant
3. dry weight of stems/plant
4. dry weight of ears/plant
b. yield and yield components 110 from sowing
1. plant height
2. ear height
3. ear length
4. ear diameter
5. number of ears/plat
6. weight of grains/ear
7. grain shelling percentage
8. a hundred-grain weight
9. grain yield (kg/fed)
IO.straw yield (tlfed)
4. Grain protein percentage
a. crude protein percentage
b. oil percentage
c. total carbohydrate percentage
The results can be summarized as follows:
A. Effect of tillage systems:
1. Tillage systems had no significant effect on bulk density of the soil
averaged over the three soil depths. However, the value of bulk density
was increased with the increase in soil depth.
2. Tillage systems did not significantly affected soil porosity percentage in
1993 and 1995 seasons.
3. Tillage systems had no significant on the total annual weeds after 45 and
75 days from sowing in 1993 and 1995 seasons.
4. The four tillage systems had no significant effect on growth characters
after 60 and 90 days from sowing in 1993 and 1995 seasons.
5. The effect of tillage systems on yield and yield components was not
significant in 1993 and 1995 seasons.
6. Results showed that tillage systems had no significant effect on grain
chemical contents in 1993 and 1995 seasons.
B. Effect of weed control treatments:
1. Results showed that weed control treatments had significant effect on
total annual weeds in the two seasons. Atrazine at 0.75 kg/fed plus hand
hoeing once gave the highest reduction ,in fresh and dry weight and
number of total annual weeds.
2. Chemical and mechanical weed control treatments had a significant
effect on plant height, dry weight of leaves, stems and ears. All of the
applied weed control treatments significantly surpassed unweeded
treatment in improving maize growth measurements. Meanwhile,
atrazine at 0.75 kg/fed plus hand hoeing once had the best effect on those
characters.
3. Plant height, ear height, ear length, ear diameter, number of ears/plant,
weight of grains/ear, grain shelling percentage, IOO-grain weight, grain
yield (ardabs/fed) and straw yield (ton/fed) were significantly affected by
the applied weed control treatments in both seasons. Both chemical and
mechanical weed control treatments improved most of the studied yield
characteristics of maize. Atrazine at 0.75 kg/fed plus hand hoeing once
gave the highest effect compared to the unweeded treatment.
4. Weed control treatments had significant effect on protein percentage
during 1993 and 1995 seasons but the effect on oil percentage was
obtained in 1993 only. Weed control treatments had no significant effect
on carbohydrate percentage during 1993 and 1995 seasons, but effect the
on oil percentage was significant only in 1993 season.
C. Effect of interaction
1. Results showed that interaction between the applied weed control
treatments and soil tillage systems had no significant effect on the total
annual weeds after 45 and 75 days from sowing in both seasons, except
for the number of weeds after 45 days from sowing as well as fresh
weight of weeds after 75·days from sowing in 1993 season.
2. The interaction effect between weed control treatments and soil tillage
system had no significant effect on growth characters in both seasons
after 60 and 90 days from sowing except for the dry weight of-stems after
60 days from sowing in 1995 season and dry weight of ears .after 90 days
from sowing in 1993 season.
3. The interaction effect between weed control treatments and soil tillage
system had no significant effect on yield and yield components in both
seasonsexcept for grain yield in 1993 season.
4. Data showed that the interaction between the applied weed control
treatments and soil tillage systems had no significant effect on grain
chemical contents in both seasons except for oil percentage in 1993
season.