SOYBEAN RESEARCH

cv. Giza 35 to increase dry matter
accumulation in the different parts of the
plant during soybean growth and
development.
Aggressivity (Agg): Aggressivity
determines the difference in competitive
ability of the component crops in
intercropping association. The positive
sign indicates the dominant component
and the negative sign indicates the
dominated component. Higher numerical
values of aggressiveness denote greater
difference in competitive ability, as well
as, bigger difference between actual and
expected yield in both crops. The results
indicated that the value of aggressivity of
corn was positive for all treatments,
while, the values of aggressivity was
negative for all intercropped soybean
with corn plants in the combined data
across 2013 and 2014 seasons (Fig. 4).
These data show that corn and soybean
plants are dominant and dominated
components, respectively.
Fig. 4. Aggressivity (Agg) as affected by ridge width, soybean cultivars and their
interaction, combined data across 2013 and 2014 seasons
In general, the highest negative values
were obtained by growing soybean cv.
Giza 21 with corn plants in ridges 60 cm
width, meanwhile, intercropping soybean
cv. Giza 35 with corn plants in ridges 70
cm width had the lowest negative values.
It is obvious that canopy structure of
soybean cv. Giza 35 (Table 1) played a
major role in coexistence with tall plants
when grown together on ridges 70 cm
width which decreased aggressivity
between the two species.
Economic analysis
The financial returns showed
that intercropping soybean with corn
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