Record ID No. |
343 |
Author(s) |
Osunde A.O., Bala A., Gwam M.S., Tsado P.A., Sanginga N., Okogun J.A. , 2003 |
Affiliation |
Fed University of Technology, Department of Soil Science, PMB 65, Minna, Niger State, Nigeria |
Title |
Residual benefits of promiscuous soybean to maize (Zea maysL.) grown on farmers' fields around Minna in the southern Guinea savanna zone of Nigeria |
Source. Vol.(no):Page |
Agriculture Ecosystems and Environment. 100(2-3): 209-220p. |
Categories |
Arbuscular Mycorrhiza |
Subjects |
Biological Interaction |
Sub-subjects |
Miscellaneous |
Host |
n.a. |
Organism |
n.a. |
Country |
Nigeria, Africa |
Abstracts |
Biological nitrogen fixation (BNF) by promiscuous cultivars of soybeans (Glycine max (L.) Merr.) in cereal-based cropping systems of Nigeria's moist savanna zone offers a potential for minimizing the investment made by resource-poor farmers on nitrogen fertilizers. A 3-year trial was conducted on five farmers' fields in the southern Guinea savanna zone of Nigeria to assess the residual effects of two successive crops of promiscuous soybean cultivars on the yield of a following maize (Zea mays L.) crop. The soybean cultivars, TGX1456-2E (medium maturity) and TGX1660-19F (late maturity), were grown in 1996 and 1997. Treatments, imposed only in the first year of the trial, were: (i) uninoculated, (ii) inoculated with a mixture of two Bradyrhizobium strains, and (iii) fertilized with 60 kg N ha(-1). A fourth treatment was a plot left to fallow. In 1998, all the previous soybean and fallow plots were sown to maize without any fertilizer application. Results in 1996 and 1997 showed a soybean response to inoculation in the first year, but differences due to the residual effect of inoculation in the second year were not significant. Both cultivars showed a similar response to inoculation but responses at the five sites were varied. Soybean cultivar 1456-2E fixed 43-52% of its N amounting to 56-70 kg N ha(-1) and cultivar 1660-19F derived 39-54% of its N from N-2-fixation which amounted to 51-78 kg N ha(-1). Both cultivars had a high N harvest index resulting in a net removal of 52-95 kg N ha(-1) when both grain and stover were exported. Even when the stover was returned, there was a depletion of 23-65 kg N ha(-1) with 1456-2E removing more N than 1660-19F. Arbuscular-mycorrhizal infection on maize roots was 11-27% and dependent on previous soybean treatments and farmers' fields. Plant height, shoot biomass, grain yield, and N uptake of maize were significantly greater in plots previously sown to soybean than in the fallow plots. In general, plots sown to the late maturing cultivar 1660-19F exhibited better residual effect, producing larger yield parameters than the plots planted with medium maturing 1456-2E. |