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The persistence of inoculants from year to year in soybean [Glycine max (L.) Merr.] cultivation and the residual benefits in soybean production are pertinent to adopting such practices in sub-Saharan Africa countries such as Ghana. A study was conducted to determine the residual effect of commercial rhizobium inoculants on soybean and selected soil health parameters after three cropping seasons. The experimental design was a split-plot. The main plot consisted of three soybean cultivars (Jenguma, Afayak, and Songda), and the subplot comprised of three peat-based commercial bradyrhizobium inoculants (Biofix, Legumefix, and NoduMax) and an uninoculated control. Assessments were made on nodulation, shoot dry matter (DM), grain yield, grain total N uptake, permanganate-oxidizable carbon (POXC), soil pH, and potentially mineralizable C. Among the soybean cultivars, Afayak produced greater nodule mass on the lateral root and the whole root system compared with the other cultivars. Jenguma and Afayak yielded greater shoot DM relative to Songda. Regarding the inoculants, Biofix increased nodule mass on the lateral root and the whole root system compared with the control. Biofix and NoduMax produced superior grain yield relative to the control. Biofix also produced greater grain yield than Legumefix. A superior pod harvest index and an improved grain total N uptake were produced by Biofix compared with Legumefix and the control. Commercial inoculants enhanced POXC availability at harvest, whereas potentially mineralizable C declined with inoculation treatments.Commercial inoculants (Biofix and NoduMax) enhanced nodulation, grain yield, and selected soil health indicators 3 yr after inoculation.

Core Ideas Combining Zn sulfate‐coated urea with low percent NBPT improved ammonia volatilization control in low pH soil when compared to the recommended NBPT application rate. Combining Zn sulfate‐coated urea with boron compounds provided ammonia volatility control. The inhibitory effect of urea coated with Zn sulfate alone on ammonia volatilization is influenced by soil properties. A study was conducted to determine ammonia loss from surface‐broadcast urea, urea treated with three rates of N‐(n‐butyl) thiophosphoric triamide (NBPT), and experimental zinc sulfate (ZnSO4)‐coated urea (ZSCU) fertilizers with or without urease inhibitors. Four trials were conducted in environmentally regulated boxes over a 14‐d period. Cumulative ammonia loss from urea was 13.98, 15.57, 23.07, and 27.74% of applied N for the Mowata, Crowley H, Crowley L, and Kinder soils, respectively. Cumulative ammonia loss from urea was greater than all rates of NBPT‐treated urea (5.57–13.35%) and ZSCU fertilizer containing urease inhibitors (2.63–11.50%) across soil types. The number of days after fertilization when the maximum rate of ammonia loss occurred increased with each incremental increase in NBPT rate for the Mowata and Crowley L soils, increased between the 0.3 and 0.6 g kg−1 NBPT rates for the Crowley H soil, and increased between the 0.6 and 0.9 g kg−1 NBPT rates for the Kinder soil. Only one of the experimental ZSCU fertilizers (zinc sulfate‐coated urea with boron and NBPT [ZUN]; Crowley H soil only) increased the number of days after fertilization when the maximum rate of ammonia loss occurred; however, the volatilization rate was lower than urea for all ZSCU fertilizers across soils. The ZUN and ZUC were the most effective ZSCU fertilizer in minimizing cumulative ammonia volatilization by 58 to 81%. The ZSCU fertilizers have the potential to reduce ammonia losses as compared to urea; however, ZSCU fertilizers with B and NBPT were the most effective.

Under increasing frequency and intensity of extreme weather events, the natural wet-dry cycles of different intensities can induce soil carbon (C) and nitrogen (N) transformation and may contribute to increased nitrous oxide (N 2 O) and carbon dioxide (CO 2 ) emissions from cultivated soils. While cover crop residue addition is a viable strategy to improve soil health, their impacts on soil greenhouse gas (GHG) emissions, especially N 2 O emissions, in response to wetting-drying intensities have received limited attention. A 3-factorial laboratory incubation was conducted using soils from a longterm experiment to examine cover crop residue roles on N 2 O and CO 2 emissions when exposed to different intensities of wetting-drying cycles. These factors included (i) cover crop residue (3 levels): no cover crop, winter wheat (Triticum aestivum L.), and crimson clover (Trifolium incarnatum

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