الفهرس 
IntroductionOnly 14 pages are availabe for public view
 |  | from | 178 |  |  |
| | | from | 178 | | |
Abstract
Two field experiments were carried out at Nubaria
Experiment Station, Agricultural Research center, to
study biological and economical efficiencies of some
combinations of two intercropping systems, i.e.,
maize/soybean and maize/sunflower in 1991 and 1992
seasons under calcareous soil conditions. Cultivars used
of the Intercrops were maize, three way cross, Giza 310,
f
soybean cv. Crawford and sunflower cv. Pioneer hybrid No.
1. Intercropping treatments were two rows of maize
alternated With four rows of soybean (or sunflower),
(2:4), alternative pair of rows (2:2) and alternative
triplet of rows (3:3). The intercropping patterns were
checked against sole cropped maize and saoybean in the
first system and maize and sunflower in the second
system. plant densities of the check plants were 24, 120
and 24 thousand plants of maize, soybean and sunflower,
respectively. Maize or sunflower were seeded
simultaneously in ’hills, 25 cm. apart on one side of the
ridges, whereas, soybean was seeded three days after
irrigation in hills, 20 cm apart on both sides of the
ridges. Thinning was carried out leaVing one plant/hill
for both maize and sunflower, but leaving two plants/hill
in case of soybean.
128
All treatments of both experiments were assigned in
complete randomized block design in four replications.
Results obtained could be summarized as follows:
FIRST EXPERIMENT
INTERCROPPING MAIZE WITH SOYBEAN
A) Maize growth, yield components and yield:
1- Plant height of maize was not significantly
influenced by intercropping pattern. Nevertheless,
no any maize plants in the intercrop combination
studied did catch up in height with sole cropped
maize.
2- Ear height on maize plants was not also influenced by
inter cropping. Nevertheless,ear height In alternate
pairs of rows was ever the farthest from the
grounnd. There was also no relevance between the
topmost ear leaf area and the intercroppinq system.
3- The effect of intercropping on the average number of
leaves per plant was not significant. The trend was
also not regular.
129
4- Ear length as well as ear diameter of maize grown in
the alternative row pattern (2:4) ranked first or
second, whereas, ear length and ear diameter of
maize plants grown in equal alternative pair of rows
with soybean ranked first in 1992, but were the
second in 1991 season.
5- Maize plants in 2:4 pattern had the highest number of
grains/row. The equal alternative row patterns
(3:3) and (2:2) ranked the second and the third,
respectively, within the intercrop combinations.
Pure stand plants exceeded the latter two patterns
in this trait.
6- Maize plants in (2:4) pattern beared more ears on the
stalk than other intercrop combinations. On other
hand, values equalized with those recorded on those
grown solid.
7- Maize plants in (2:4) pattern had the heaviest ear
weight when compared with other intercrop combinations.
Differences with other intercrop combinations
were significant. On other hand, equal alternative
rows poattern (2:2)had the least values. Neverthless
none of the intercrop combinations had an average
ear weight heavier than the sole cropped maize.
8- Pattern (2:4) had the highest values of both seed
index as well as shelling percentage over all other
cropping systems in both seasons, although
differences were not significant in most cases.
9- ”Actual” yield of maize plants grown alone was ever
more than that obtained from other intercropping
treatments. Pattern (2:4) produced the lowest
yield/fad., whereas, the equal alternative rows
(2:2) and (3:3) ranked the second and the third,
respectively. Differences in yield between the pure
stand maize and the intercrop treatments were
significant. Significant differences in yield were
also apparent between maize grown in the equal
alternative row patterns (2:2), (3:3) and the
alternative row pattern (2:4).
10- The ”adjusted” yields of maize in the intercrop
combinations were higher than yield of maize grown
in pure stand. The results also indicated that
maize grown in the equal alternative row paatterns
(2:2) and (3:3) outyielded that obtained from the
(2:4) pattern.
B) soybean growth, yield components and yield/fad
1- The tallest soybean plants we%e associated with the
equal alternative pair of roWS. solid plants ranked
the second, whereas, (3:3) and (2:4) patte%ns %anked
the third and the fourth, respectivelY·
2- soybean plants in the alternative patte%n (2:4) had
more branches/ plant. sole cropped soybean ranked
the second, whereas, the equal alternative row
patterns (2:2) and (3:31 occupied the third and the
fourth ranks 1n both seasons. Significancy was observed
among all treatments in the first season and
between (3:3) and solid planting in the second one.
3- soybean plants qrown in pure stand had the hlqhest
average number of pods/plant, whereas, those
oriented in (2:4) pattern ranked the second (Only in
1992 season). But equal alternative row (2:2) and
(3:3) patterns ranked the third and the fourth,
respectively. Differences among all t%eatments were
significant in the fi%st season.
4- The effect of intercropping patterns on seed index of
soybean behaved similarly as recorded with other
t%aits. Highest values were obtained when soybean
oriented in the equal alternative row patterns
and (2:
2
) occupied the third and the fourth
respectively.
132
(3:3)
rank,
5- The ”actual” yield of soybean gro~ alone
significantly exceeded yields of soybean in all
intercrop combinations under study. The data also
indicated that soybean in (2:4) pattern outyielded
that of both equal pairs or triplet alternative row
patterns.
6- The ”adjusted” yield of the intercropped soybean
within any intercropping pattern was superior to
that obtained from the sole cropped soybean. The
increase has been diminished between soybean grown
in (2:2) pattern and soybean grown in pure stand.
C) competitive relationshiPs and yield advantages
1- Relative yiel (RY) values of maize or soybean were
proportionall parallel with their areas gro~ in
the intercrop associations. RY values of maize were
higher than expected in all the intercrop
combinations.
2- Results of land equivalent ratios indicated that all
Intercrop combinations gave more yield advantage as
compared with sole cropped maize or soybean. All
LERs values obtained exceeded the unit in both
seasons.
The data also indicated that arranging
both components in mixture of equal alternative
patterns, i.e., (2:2) or (3:3) gave yield advantage
more than (2:4) pattern.
3- Results of the relative crowding coefficient
indicated that all K values, i.e., Km and KS gave
yield advantage more than expected in any of the
Intercrop combinations in both seasons. The results
also revealed that all Km values within these
patterns were relatively higher than those
calculated for soybean plants. Results also
indicated that Km and Ks values were positively
correlated with the proportion of both components 1n
the intercropplng systems.
The more the crop grown
area in the mixture was, the higher K value was
obtained.
4- Aggressivity data indicated that the treatments
effect of both the equal alternative row arrangement
had relatively higher mutual competitive pressure on
both crops than in (2:4) pattern. The results also
134
indicated that maize was always the dominant
component, whereas, soybean was the dominated
component in all intercropping combinations.
5- Results showed that maize was always more competitive
than soybean in most of the intercrop combinations
in both seasons. All eRs values of maize exceeded
the unit, except, in 1992 season when maize was
alternated with soybean in (2:4) ratio. eRs values
of soybean were always lower than the unit, except,
when soybean proportion was increased to its maximum
in (2:4) pattern in 1992.
The results also revealed that maize component had
more competitive ability than soybean, except in case of
(2:4) pattern where soybean had greater area in the
mixture.
D) Economic evaluation :
1- Results indicated that (2:2) pattern produced maximum
Cereal Units from maize component, whereas, the
least was obtained from (2:4) pattern. Cereal Units
produced from soybean in (2:4) were highest,
whereas, those obtained from (2:2) pattern were the
least. Cereal Units produced from sole cropped
135
plants of either component were superior to all
those obtained from either component in any
intercroppin9 pattern. cereal units of total
”actual” yield produced from (2:2) patteln wele
relativelY the highest, whereas, (2:4) pattern
produced the least. Differences between both equal
alternative roWS patterns were very minute. cereal
units from sale cropped maize were always more than
those obtained from any intercropping pattern, but
all exceeded the sole cropped soybean.
2- The net return calculated from (2:2) and (3:3)
patterns were evidently higher than that calculated
from (2:4) pattern. pattern (2:2) had higher net
return than (3:3) pattern. On other hand, the net
return gained from each intercropping patterns
exceeded that obtained from pure stand soybean. The
monetary advantage behaved the same course of change
as the net return. The data alsO revealed that the
more the increase of LER value was, the more
monetary advantage obtained.