ABSTRACT

Two field trials were conducted in early and late seasons of 2004 at the Agricultural

Vocational Training Centre (AVTC) Otobi-Otukpo located in the southern guinea savannah

agro-ecological zone of Nigeria to evaluate the effects of varying maize population densities

(3 8000,44440 and 53330 plants/ha) on the productivity of soybean/maize intercropping

system. Three maize population densities were combined with two soybean varieties (TGX

1448-2E and Samsoy-2) each maintained at the optimum population of 266,660 plants/ha in

both the intercrop and sole crop. Sole crops of maize (TZR-EW) were maintained at 53330

plants/ha as controls. Early cropping was sown in May 2004 while late cropping was in July,

2004. The intercropping system did not in the overall have significant effect on soybean seed

germination, number of leaves, days to 50% flowering and podding, nodules per plant,

nodule weight, pod length, seeds per pod and seed yield of soybean and also tasseling, silking

and ear height of maize. There was significant intercropping effects on plant height, pods per

plant, 100 seed weight and 50% flowering (late) of soybean. The interaction effects of maize

population x soybean variety were not significant for soybean seed germination, plant height,

number of leaves, days to 50% flowering and podding, nodules/plant, nodule weight,

pods/plant, pod length and seeds per pod, 100 seed weight and tasseling, silking and ear

height of maize. However, interaction effects on soybean yield (early) and maize yield (late)

were significant at all population densities of maize. Samsoy-2 was best at 38000 maize

population only for early season planting while TGX 1448-2E was best at 53330 plants/ha for

late season cropping. There were significant varietal differences in seed germination, number

of leaves at 8 WAP (early), plant height except at 8WAP (early), days to 50% flowering and

podding, nodules and nodule weight, pods per plant, pod length, seeds per pod (early), 100

seed weight (late) of soybean and seeds per cob (late), seed yield (late) of maize. Under

cropping system, there were significant varietal differences in seed yield of soybean, but

effect of intercrop system was non-significant. Land equivalent ratio (LER) was highest at

38000 plants/ha for Samsoy-2 (early) and at 53330 plants/ha for TGX1448-2E (late)

indicating higher productivity arising from the degree of expression of complimentarity of the

component crops in the cropping system.