last final thesis of umer

Aboveground biomass (kg ha -1 )
Dry aboveground biomass was significantly (p<0.05) affected by the planting density of the
associated cowpea and cropping system but non-significantly affected by variety and the
interaction of variety with planting density (Appendix Table 3). The highest (8537 kg ha -1 ) and
lowest (4643 kg ha -1 ) biomass of maize was recorded from maize intercropped with cowpea at
50% and 100% planting density, respectively (Table 9). The higher biomass at 50% might be due
to less planting density that might have resulted in less competition between maize and cowpea
for the resources. This is in line with the findings of Mitiku & Getachew (2017) who reported that
rice dry biomass significantly decreased as common bean density increased from 25% to 75% in
rice/common bean intercropping. With regard to cropping system, sole maize (11682 kg ha -1 ) was
significantly superior (P<0.05) than the intercropped maize (6507 kg ha -1 ) (Table 9). This could
be due to less competition between the component crops. This result is in line with Siddig et al.
(2013), who reported that dry matter weight of sorghum was negatively influenced due to
sorghum-ground nut intercropping.
Grain Yield (kg ha -1 )
Grain yield of maize was highly significantly (p<0.01) affected by planting density and cowpea
varieties as well as their interaction while cropping system was significant (p<0.05) (Appendix
Table 3).The highest maize yield (3184 kg ha -1 ) was obtained from the combinations of maize x
50% plant population of cowpea variety kenketi while the lowest grain yield (1271 kg ha -1 ) was
obtained from combination of maize x 100% plant population of cowpea variety Bole (Table 8).
The highest grain yield of maize from 50% population of cowpea variety Kenketi might be due to
reduction in competition for growth resources and early maturity of the intercropped cowpea
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