Integrated Soil Fertility Management and its Role in the Sustainable Intensification of Smallholder farming systems in Sub-Saharan Africa

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1 Integrated Soil Fertility Management and its Role in the Sustainable Intensification of Smallholder farming systems in Sub-Saharan Africa African Green Revolution Forum 2 4 September, Addis Ababa - Ethiopia AGRF2014 1

2 Since the 1960s, crop production has increased but mostly through land expansion AGRF Addis Ababa 03/09/2014 2

3 but growth has not been enough; population increase has been continuously higher than land expansion or yield increase (with regional differences) AGRF /09/2014 3

4 How will growth be achieved? The potential differs per country and even within country! AGRF /09/2014 4

5 Growth, where is it going to come from? Cultivating new land - Increasing yield - Improving cropping intensity - Shifting to other crops AGRF /09/2014 5

6 Low population and remote areas: expansion? AGRF /09/2014 6

7 0.5 1 ha Densely populated areas: Intensification AGRF /09/2014 7

8 There are opportunities to increase cropping intensity and make better use of the available water, but.. AGRF /09/2014 8

9 A focus on densely populated areas and improved nutrient management (Crop yields in Africa are constrained by nutrient limitations) AGRF /09/2014 9

10 Yields vary strongly from one farm to the other: Increase yields on poor performing farms to increase average yield, but.. Source: Jayne et al, what explains the variation? IPI-ATA Symposium 04/09/

11 The Green Revolution in Africa will remain illusory unless the fundamental issues of providing the plant with adequate nutrients under highly variable conditions are properly addressed Hardy 1998 Fertilizers are key, but how to ensure fertilizer use efficiency for these very different environments? IPI-ATA Symposium 04/09/

12 Grain yield (t/ha) Grain yield (t/ha) Grain yield (t/ha) Grain yield (t/ha) Response to fertilizer application may be poor, or depend on additional soil amendments like manuring, liming or micronutrient application we need adaptive fertilizer strategies 7 6 No response; low grain yield levels (2 t/ha); 25% of the cases 7 6 Intermediate soil fertility; N&P gives t/ha; manure: 5 t/ha; 35% of the cases 7 6 Limited response; yields up to 3 t/ha; 28% of the cases 7 6 Responsive; esp. to N up to 5 t/ha; Manure/MN 6-7 t/ha; 11% of the cases Co -N -P -K NPK +L +Ma +MN Co -N -P -K NPK +L +Ma +MN Co -N -P -K NPK +L +Ma +MN Co -N -P -K NPK +L +Ma +MN IPI-ATA Symposium 04/09/

13 There are marked differences between sites, but also within sites: requires spatially explicit soil management recommendations Resp N, rel. fert. Non Resp - Fert Resp N&P, intermed fert Poor Resp. low fert. Non Resp - Poor Resp. P&N IPI-ATA Symposium 04/09/

14 Integrated Soil Fertility Management Improving Agronomic Efficiency (through a stepwise approach) Step 1 Current practice refers to the current average fertilizer application rates of 8 kg fertilizer nutrients ha -1. Step 2: Use of improved germplasm, improved seed and fertilizer use Step 3: Organic Resource Management (improved) Step 4: Adaptation to local conditions Response to use of improved Inputs varies: Responsive vs. non-responsive soils; path A indicates potential benefits of seed + fertilizer on responsive soils, paths B and C depict the need to invest in rehabilitation of non-responsive soil through improved ORM before the seed + fertilizer components will enhance yields. IPI-ATA Symposium 04/09/

15 We are nowhere near to achieving the target of 50 kg/ha of fertilizer use on average, set in the Abuja declaration (2006) for 2015!! Concerted action is required to diagnose soil nutrient limitations and additional soil health constraints, recommend proper strategies for integrated soil fertility management (evidence-based), and make sure that smallholder farmers have access to appropriate, and quality fertilizers and access to information on its proper use and accompanying management practices that improve fertilizer use efficiency IPI-ATA Symposium 04/09/

16 Support the Soil Research 4 Development sub-regional and pan-african platform IPI ATA symposium 04/09/