Corralling, planting density and N fertilizer rate effect on soil, weed and maize yield. Abdul Rahman Nurudeen, Larbi Asamoah Opoku Andrews, Francis Marthy Tetteh and Hoeschle-Zeledon Irmgard

Outline of presentation Introduction Materials and methods Conclusions Recommendations

Introduction Background Current farming system in Africa is intensifying across various agro-ecological zones (Sanginga et al., 2003). Increase in human and livestock growth is leading to crop-livestock intensification (Powell et al., 2004). Staple crops grown are mainly cereals (maize, rice, millet and sorghum). Livestock reared are mainly ruminants with poultry and little mono-gastric.

Introduction … Problem Statement Crop yields on farmers field are low due to: Erratic rainfall Low soil fertility (Bationo et al., 2000). Poor integration of crop and livestock enterprise (Tarawali et al., 1999). Poor agronomic practices: Low planting densities Blanket fertilizer application

Introduction … Justification Livestock corralling results in high crop yields (Powell et al., 2004; 2014). N fertilizer use (Buah et al., 2009; Abdul Rahman et al., 2015). Increasing planting density (Conley et al., 2005; Adeniyan, 2014). Blanket fertilizer recommendation not useful in recent times. Conflicting results on effect of plant density on yield of maize. Much remains unknown on the interaction effect of these three factors on grain yield in crop-livestock system in West Africa.

Introduction … General Objective: To determined the interaction effect of SDSG, MPD and NFR on yield of maize in a small-scaled crop-livestock system. Specific objectives: To determine effect of: SDSG on soil properties. SDSG on weed diversity. Interaction effect of SDSG, MPD and NFR on yield of maize.

Materials and Methods Study Area: Upper East (Sudan Savanna) Longitude:10̊ 30’ 11’’ N Latitude: 0̊ 1’ 30’’ W Environ. Conditions TMean annual Max.: 34.3̊ C TMean annual Mini.: 22.3̊ C Mean annual Rainfall: 750-1204 mm (Source: Navrongo Meteo. Depart.)

Experimental Design: Split-split plot with 8 reps. Main plots: Stocking density of sheep and goat corralling(SDSG) (0, 70, 140 heads ha-1) Sub plots: Maize plant density (MPD) (66 667, 100 000, 133 333 plants ha-1) Sub-sub plots: N fertilizer rate (NFR) (0-40-40, 60-40-40, 90-40-40 kg ha-1 NPK)

Photo 1: Stocking density of sheep and goat corralling (SDSG)

Photo 2: Manure and soil sampling from SDSG plots Manure quality TN AP EK Lining Polyphenol C/ N Soil properties pH OC MBC MBN Photo 2: Manure and soil sampling from SDSG plots

Results and discussions Table 1. Manure chemical properties   Total OC Total N Total P Total K Polyphenol Lignin C/N Farm (g kg-1)  ratio 1 184.0 19.0 5.0 11.0 62.0 119.0 9.8 2 220.0 4.0 59.0 105.0 11.7 3 223.0 20.0 9.0 60.0 116.0 11.4 4 144.0 18.0 3.0 6.0 73.0 124.0 8.0 5 164.0 78.0 143.0 8.4 6 128.0 24.0 7.0 47.0 7 200.0 2.0 33.0 74.0 8 53.0 85.0 9.2 Mean 178.0 58.0 106.0 9.5

Table 2. Soil properties as affected by SDSG in northern Ghana, 2014 and 2015 cropping season.   SDSG (heads ha-1) Contrast2 Variable1 70 140 s.e P-value 0 vs (70 + 140) 70 vs 140 2014 season pH (H2O) 5.1 5.4 5.5 0.05 *** ns OC (g kg-1) 7.3 12.3 14.9 0.69 * Total N (g kg-1) 0.4 0.5 0.6 0.02 ** Available P (mg kg-1) 2.0 2.8 2.06 Exchangeable K (cmol kg-1) x 10-2 4.3 9.3 11.8 3.54 Microbial biomass carbon (g kg-1) 241.9 328.9 352.5 14.27 Microbial biomass nitrogen (g kg-1) 18.7 21.8 21.2 0.80 2015 season 5.8 0.12 15.4 18.2 0.44 0.8 0.9 2.5 3.8 3.4 0.26 20.8 24.9 3.17 260.0 358.7 384.8 10.80 22.9 26.3 26.9 0.52

Table 7. Weed species count as affected by SDSG   SDSG (heads ha-1) Contrast1 Weed species (m-2) 70 140 s.e p-value 0 vs (70 + 140) 70 vs 140 2014 season Broadleaf 6.1 (0.8)2 8.4 (0.9)2 8.9 (0.9)2 0.02 ** *** ns Grass 2.4 (0.4)2 3.8 (0.6)2 5.0 (0.7)2 0.03 Sedge 1.6 (0.2)2 3.4 (0.5)2 3.6 (0.6)2 0.04 2015 season 6.3 (0.8)2 8.0 (0.9)2 9.5 (1.0)2 2.1 (0.3)2 4.8 (0.7)2 4.8 (0.6)2 2.3 (0.3)2 3.1 (0.5)2

Table 2. Maize grain yield as affected by SDSG and MPD

Fig. 3. Maize grain yield as affected by SDSG and NFR

Conclusions Corralling of sheep and goat improved soil properties. Corralling of sheep and goat increased weed diversity. SDSG and MPD interaction increased maize grain yield by about 92%. SDSG and NFR interaction also increased maize grain yield by 92%.

Recommendations Maize-livestock farmers with low resource endowment may also corral sheep and goat 70 or 140 heads ha-1 with maize plant density at 100 000 plants ha-1 for increased grain yield. Those with low number flock size can corral at 70 heads ha-1 with mineral fertilizer at 90 kg ha-1 N for high grain yield. Those with large flock size can also corral at 140 herd ha-1 with mineral fertilizer at 60 kg ha-1 N for increased grain yield.