Potential of Inoculant and Phosphorus Application on Soybean Production in Mozambique

Abstract

Inoculation with effective Bradyrhizobium spp., and phosphorus application enhance atmospheric nitrogen fixation in soybean production. Soybean form symbiotic associations with the right rhizobium strain to incorporate atmospheric nitrogen into the plant tissues. The objective of this study was to evaluate responses of two soybean varieties to inoculation, phosphorus and starter-nitrogen, and their interactions on nodulation, growth, yield components and grain yield in different agroecologies of Mozambique. The study was conducted at three locations in Nampula, Tete and Zambézia provinces in Mozambique during 2012 and 2013 seasons. Two soybean genotypes (Storm and TGx 1904-6F) in split-plot design with phosphorus (P 2 O 5 ) rates as main plot, inoculation application as subplots and nitrogen rates as sub-sub plots with four replications were used. Nodulation, plant growth, biomass nutrient content at R3 stage, yield and yield components were evaluated. Data analyzed for combined and individual locations in Statistical Analysis System ® 9.4 indicated that inoculation increased nodulation and yield (37% to 95%) in both soybean genotypes but the effect of phosphorus on nodule formation was not consistent across sites and varieties. Inoculants have a potential to supply required nitrogen for soybean production in Mozambique because farmers seldom use mineral fertilizers due to its high cost.

Inoculant, nitrogen and phosphorus improves photosynthesis and water-use efficiency in soybean production

“…From our experiment, promiscuous variety TGx 1740-2F accumulated more N and K in the above ground biomass at R3 stage than the non-promiscuous, Safari. Accumulation of N and K was also documented at R3 stage in cowpea that were either inoculated or received P fertilizer (Kyei-Boahen et al, 2017) and soybean (Savala and Kyei-Boahen, 2020). Accumulation of N and K in TGx 1740-2F could be related to elevated transpiration.…”

“…These studies focused on the growth and development characteristics that led to the yield observed following N and P application but not the physiological, phenological and WUE changes due to agronomic practices. Inoculants contain effective rhizobia that enhance symbiotic biological nitrogen fixation (BNF) in soybean (Sanginga et al, 2002;Zimmer et al, 2016;Savala and Kyei-Boahen, 2020). Similar to P, supply of N either through BNF or mineral fertilizer promote plant growth that stimulates increased photosynthesis activity in plant leaves.…”

Meta-analysis of the effects of Rhizobia inoculants and phosphorus fertilizer on soybean nodulation in Africa

“…The effects of Rhizobium inoculation and phosphorus fertilizer on soybean performances were estimated using the random-effects model (REM) described by Viechtbauer (2010). The statistical analyses in this study were all performed in R version 4.0.2 (R Core Team, 2020), using the R program Metafor (Viechtbauer, 2010;Schwarzer et al, 2015). The Escalc() function contributed to calculate the standardized mean differences (SMD), which measure effect sizes that allowed comparing treatments to the controls (Viechtbauer, 2010).…”

“…The Escalc() function contributed to calculate the standardized mean differences (SMD), which measure effect sizes that allowed comparing treatments to the controls (Viechtbauer, 2010). The REM was used to estimate the average true effect and the total amount of heterogeneity among the true effects (Viechtbauer, 2010;Schwarzer et al, 2015). Results were presented in form of forest plots with the Forest() function (Lewis and Clarke, 2001) and boxplots using the Plot() function (Viechtbauer, 2010).…”

“…A Funnel plot is a simple scatter plot for the study's estimated treatment effects (x-axis) against the measure of study size on the y-axis (Sterne et al,, 2001). Trim and fill method using the Trimfill() function (Viechtbauer, 2010;Schwarzer et al, 2015) was applied on asymmetrical Funnel plots to determine the effect of missing studies on the overall outcome. The standardized mean difference for the study was plotted on the horizontal axis against the standard error on the vertical axis.…”