An important consideration for the application of this type of
system in a production setting is finding the optimum plant
spacing to meet the needs of all component species. In the past,
there has been debate regarding planting density and plant spacing when calculating LER for comparing monocultures with mixed
cropping systems (Oyejola and Mead, 1982). Optimum plant
densities in monoculture have been suggested for best achievable
yields (Huxley and Maingu, 1978), and deviation from these
planting densities will reduce the yield of the monocultures and
thus bias LER toward the mixed plantings. However, in some
instances when certain variables are being isolated it is appropriate
to maintain similar densities across treatments (Mead and
Willey, 1980). In order to assess the impact of increasing plant
functional diversity on yield without the added complication of
planting density, planting density was kept stable across the plots
and thus sometimes planted the monocultures at slightly larger
than optimal planting densities. Monoculture of peanut, pepper
and cowpea were planted at less than optimal density. With the
exception of number of pods per cowpea plant, these species were
the least responsive to mixed cropping with regards to fruit quality
and consistently underyielded. It was found that underyielding in
cowpea was due to a reduction in the number of pods per plant.
Monoculture of okra was planted at optimal density and, although
the optimal density of this particular variety of mini watermelon
used is not known for certain, we believe it was planted at slightly
higher than optimal density. Okra and watermelon were the most
responsive to changes in planting densities and multi-cropping
combinations with regards to both production and fruit quality.
Therefore, there should have been little or no bias on our LER
results due to planting densities as suggested by some authors.
An important consideration for the application of this type ofsystem in a production setting is finding the optimum plantspacing to meet the needs of all component species. In the past,there has been debate regarding planting density and plant spacing when calculating LER for comparing monocultures with mixedcropping systems (Oyejola and Mead, 1982). Optimum plantdensities in monoculture have been suggested for best achievableyields (Huxley and Maingu, 1978), and deviation from theseplanting densities will reduce the yield of the monocultures andthus bias LER toward the mixed plantings. However, in someinstances when certain variables are being isolated it is appropriateto maintain similar densities across treatments (Mead andWilley, 1980). In order to assess the impact of increasing plantfunctional diversity on yield without the added complication ofplanting density, planting density was kept stable across the plotsand thus sometimes planted the monocultures at slightly largerthan optimal planting densities. Monoculture of peanut, pepperand cowpea were planted at less than optimal density. With theexception of number of pods per cowpea plant, these species werethe least responsive to mixed cropping with regards to fruit qualityand consistently underyielded. It was found that underyielding incowpea was due to a reduction in the number of pods per plant.Monoculture of okra was planted at optimal density and, althoughthe optimal density of this particular variety of mini watermelonused is not known for certain, we believe it was planted at slightlyhigher than optimal density. Okra and watermelon were the mostresponsive to changes in planting densities and multi-croppingcombinations with regards to both production and fruit quality.Therefore, there should have been little or no bias on our LERresults due to planting densities as suggested by some authors.
การแปล กรุณารอสักครู่..
