Response of corn-snap bean intercrop to inoculation with specific nydrogen-fixing bacteria under an alley cropping systems

The study was conducted to 1) compare the yield of inoculated and uninoculated corn and snap bean in an alley-cropping system; 2) determine the effects of inoculation and the cropping system on the biological and chemical properties of the soil; 3) assess the economic benefits of corn and snap bean inoculation and fertilization in alley cropping system. This study was laid out in split-plot Randomized Complete Design (RCBD) with inoculation as the main plot and fertilizer rate as the sub-plot treatment replicated 3 times. The result showed that inoculation did not significantly improve the fresh and dry weights of corn and snap beans. However, corn yield was significanty affected by inoculation with BI0-N. The unhusked and husked yield was significantly higher (6,275 kg/ha and 4,038 kg/ha, respectively) compared to the uninoculated plot (5,201 kg/ha and 3,525 kg/ha). Nodulation in snap bean was improved by Nitroplus inoculation and consequently improved the number of pods per plant from 8 to 13 nodules. Fresh snap bean yield was not significantly affected by inoculation but significantly affected by N fertilization. Higher snap bean yield was obtained under the FRR and 1/2 plots across the main plot treatments. Soil pH, soil organic matter, %N, available phosporous and exchangeable potassium were not significantly affected by inoculation of nitrogen fixing bacteria.Meanwhile, micobial count showed that actino-mycetes and bacterial population in the inoculated plots increased in population of bacteria. The fungal population slightly decreased in all treatments after the study. The changes, however were not significant. The economic analysis showed that corn inoculation with BIO-N in the absence of inorganic nitrogen provide the highest income after fertilizer at P 132,660 /ha. On the other hand, Nitroplus inoculation plus fertilizer application at 15 kg N/ha gave the highest return for snap bean at P23, 815.50/ha.