Consortium for the improvement of agriculture- based livelihoods in

1. Consortium for the improvement of agriculture- based livelihoods in Central Africa The potential of Integrated Soil Fertility Management for increasing cassava productivity in sub-Saharan Africa B Vanlauwe, P Pypers, N Sanginga TSBF-CIAT, Nairobi, Kenya

2. Consortium for the improvement of agriculture- based livelihoods in Central Africa Context of African agriculture

3. 1. Farming in SSA… LACK OF PRODUCTION FACTORS • High input prices (1 kg of NPK in East DR Congo costs 1.7 USD) • Recycling of organic residues, mainly manure (but very limited availability) • Limited labor availability (HIV-AIDS, drudgery, low appeal for young people, etc) •  Relatively small farms on relatively old soils • LACK OF AN ENABLING ENVIRONMENT •  Lack of infrastructure, market organization • Civil strife • Climate change, etc, etc,… ContextFacts ISFM Progress Concl

4. 2. Variability!  Continental scale Soils in East and Central Africa ContextFacts ISFM Progress Concl

5. 2. Variability! At the farm scale ContextFacts ISFM Progress Concl

6. 2. Variability! At the farm scale ContextFacts ISFM Progress Concl

7. 2. Variability! At the farm scale ContextFacts ISFM Progress Concl

8. 3. The opportunity… •  Finally, fertilizer and inputs are back on the agenda! • Statement in 1996 (Research Director, IITA): • ‘You can’t include fertilizer in your work since • farmers in SSA are not using fertilizer’ • The African Fertilizer Summit declaration: ‘By 2015, increase fertilizer use from 8 to 50 kg fertilizer nutrients/ha’ • The Alliance for a Green Revolution in Africa Uniquely African (K Annan): ‘Recognizing its great diversity of landscapes, soils, climates, and cultures…’ ContextFacts ISFM Progress Concl

9. Consortium for the improvement of agriculture- based livelihoods in Central Africa Facts about cassava

10. Cassava supports ± 25% of farming households in • SSA (± 100 mill people) and is a major crop on ± 35% • of all agricultural land (± 60 mill ha) ContextFacts ISFM Progress Concl

11. 2. Cassava production is increasing but mainly due to area expansion ContextFacts ISFM Progress Concl

12. 3. Cassava productivity is low in SSA ContextFacts ISFM Progress Concl

13. 4. Cassava is exporting substantial amounts of nutrients (mainly K) but requires N and K to grow NPK ratio for roots: 5 : 1 :10 NPK ratio for whole plants: 7 : 1 : 7 ContextFacts ISFM Progress Concl

14. 5. Soil fertility management in cassava systems is very much under-researched in SSA relative to other regions • Production (2004) • (www.fao.org) • SSA: 108 mill ton • LatAm: 35 • Asia: 60 • World: 203 < 30% < 5% < 2% ContextFacts ISFM Progress Concl

15. Consortium for the improvement of agriculture- based livelihoods in Central Africa Integrated Soil Fertility Mgt

16. ISFM… ContextFactsISFM Progress Concl

17. ISFM… ‘The application of soil fertility management practices, and the knowledge to adapt these to local conditions, which maximize fertilizer and organic resource use efficiency and crop productivity. These practices necessarily include appropriate fertilizer and organic input management in combination with of improved germplasm’ Agronomic efficiency = [Increase in yield]/[Fertilizer nutrient applied] ContextFactsISFM Progress Concl

18. Yield/ ContextFactsISFM Progress Concl

19. Site-specific responses to fertilizer ContextFactsISFM Progress Concl

20. Yield/ ContextFactsISFM Progress Concl

21. Yield/ ContextFactsISFM Progress Concl

22. ‘Quick approaches’ - Flyers - Demo kits - Focus on access - Etc Start scaling up today ‘Complex approaches’ - Farmer field schools - Extension expertise - Etc Medium term involvement Yield/ ContextFactsISFM Progress Concl

23. Consortium for the improvement of agriculture- based livelihoods in Central Africa ISFM and cassava

24. Cassava?? ContextFacts ISFM Progress Concl

25. STEP 1: Germplasm and fertilizer ContextFacts ISFM Progress Concl

26. STEP 1: Germplasm and fertilizer – WE KNOW… 1. Improved varieties (eg, CMD-resistant) are essential to obtain substantial yield increases; supply needs to match demand by a healthy crop local variety improved variety (Nsansi) ContextFacts ISFM Progress Concl

27. STEP 1:Germplasm and fertilizer – WE KNOW… 2. Cassava responds to fertilizer CIALCA trials in Sud-Kivu, DR Congo without fertilizer with fertilizer (2 bags of NPK ha-1) ContextFacts ISFM Progress Concl

28. STEP 1:Germplasm and fertilizer – WE KNOW… 2. Cassava responds to fertilizer but minimum benefits are needed to justify its usage CIALCA trials, Sud-Kivu, DR Congo ContextFacts ISFM Progress Concl

29. STEP 1:Germplasm and fertilizer – WE KNOW… 3. Fertilizer management affects its use efficiency Fertilizer recovery by maize ContextFacts ISFM Progress Concl

30. STEP 1:Germplasm and fertilizer – DO WE KNOW? 1. Optimal application rates for specific soils and AEZs? (Current recommendations are based on info from Asia!) Economically optimal response ContextFacts ISFM Progress Concl

31. STEP 1:Germplasm and fertilizer – DO WE KNOW? 1. Optimal application rates for specific soils and AEZs? (Current recommendations are based on info from Asia!) 2. Best fertilizer type for specific soils? (Different soils have different nutrient supply capacities!) ContextFacts ISFM Progress Concl

32. STEP 1:Germplasm and fertilizer – DO WE KNOW? 1. Optimal application rates for specific soils and AEZs? (Current recommendations are based on info from Asia!) 2. Best fertilizer type for specific soils? (Different soils have different nutrient supply capacities!) 3. Appropriate management of fertilizer relative to land preparation (flat, ridges, mounds, etc) and placement (point-placed, broadcast, etc)? (Proper fertilizer management has been shown to affect its use efficiency by other crops) ContextFacts ISFM Progress Concl

33. STEP 1:Germplasm and fertilizer – DO WE KNOW? 1. Optimal application rates for specific soils and AEZs? (Current recommendations are based on info from Asia!) 2. Best fertilizer type for specific soils? (Different soils have different nutrient supply capacities!) 3. Appropriate management of fertilizer relative to land preparation (flat, ridges, mounds, etc) and placement (point-placed, broadcast, etc)? (Proper fertilizer management has been shown to affect is use efficiency by other crops) 4. Fertilizer application and tuber quality? (Cassava+, etc) ContextFacts ISFM Progress Concl

34. STEP 2: Germpl/fert + OM mgt ContextFacts ISFM Progress Concl

35. STEP 2: Germpl/fert + OM mgt – WE KNOW… 1. Organic resources are best produced in-situ and with multiple purposes for farmers to be interested Dual purpose soybean in west Kenya ContextFacts ISFM Progress Concl

36. STEP 3: Gpl/fert + OM mgt + Loc adapt – WE KNOW… 2. Cassava-based system are sufficiently flexible to integrate various grain legumes Cassava-groundnut intercropping in Bas-Congo, DRC Cassava-cowpea intercropping in Bas-Congo, DRC Cassava-beans Intercropping In Sud-Kivu, DRC ContextFacts ISFM Progress Concl

37. STEP 3: Gpl/fert + OM mgt + Loc adapt – WE KNOW… 2. Cassava-based system are sufficiently flexible to integrate various grain legumes CIALCA trials in Sud-Kivu, DRC ContextFacts ISFM Progress Concl

38. STEP 2: Germpl/fert + OM mgt – WE KNOW… 3. Organic resources contain nutrients that can benefit cassava but their contents are most often limited for commonly available resources control ContextFacts ISFM Progress Concl

39. STEP 2: Germpl/fert + OM mgt – DO WE KNOW? 1. Do organic inputs provide other functions than substituting fertilizer nutrients that will favor cassava productivity (e.g., reduce P sorption, buffer Al toxicity)? ContextFacts ISFM Progress Concl

40. STEP 2: Germpl/fert + OM mgt – DO WE KNOW? 1. Do organic inputs provide other functions than substituting fertilizer nutrients that will favor cassava productivity (e.g., reduce P sorption, buffer Al toxicity)? 2. For maize, the combined application of organic matter and fertilizer can create added benefits that can lead to improved use efficiency of the fertilizer and/or the organic inputs for maize which is most responsive to N and P. What for cassava, which is more responsive to K? ContextFacts ISFM Progress Concl

41. STEP 2: Germpl/fert + OM mgt – DO WE KNOW? 1. Do organic inputs provide other functions than substituting fertilizer nutrients that will favor cassava productivity (e.g., reduce P sorption, buffer Al toxicity)? 2. For maize, the combined application of organic matter and fertilizer can create added benefits that can lead to improved use efficiency of the fertilizer and/or the organic inputs for maize which is most responsive to N and P. What for cassava, which is most responsive to K? 3. Which measures are needed to restore productivity on degraded, non-responsive sites? ContextFacts ISFM Progress Concl

42. STEP 2: Germpl/fert + OM mgt – DO WE KNOW? 1. Do organic inputs provide other functions than substituting fertilizer nutrients that will favor cassava productivity (e.g., reduce P sorption, buffer Al toxicity)? 2. For maize, the combined application of organic matter and fertilizer can create added benefits that can lead to improved use efficiency of the fertilizer and/or the organic inputs for maize which is most responsive to N and P. What for cassava, which is most responsive to K? 3. Which measures are needed to restore productivity on degraded, non-responsive sites? 4. Cassava leaves contain a lot of N; could a well- managed cassava crop be an entry point to boost overall system productivity? ContextFacts ISFM Progress Concl

43. STEP 3: Gpl/fert + OM mgt + Loc adapt ContextFacts ISFM Progress Concl

44. STEP 3: Gpl/fert + OM mgt + Loc adapt – WE KNOW… 1. Soil physical management for cassava production as a function of soil depth, slope, and moisture status Bas-Congo Sud-Kivu ContextFacts ISFM Progress Concl

45. STEP 3: Gpl/fert + OM mgt + Loc adapt – WE KNOW… 2. Responses to fertilizer are variable CIALCA trials in Bas-Congo, DRC ContextFacts ISFM Progress Concl

46. STEP 3: Gpl/fert + OM mgt + Loc adapt – DO WE KNOW? 1. Local diagnosis of soil fertility status? (Farmers seem to have an idea but will this be sufficient as a basis for recommendations?) ContextFacts ISFM Progress Concl

47. STEP 3: Gpl/fert + OM mgt + Loc adapt – DO WE KNOW? Local diagnosis of soil fertility status? (Farmers seem to have an idea but will this be sufficient as a basis for recommendations?) 2. Fertilizer placement relative to rainfall and physical soil preparation (ridges, mounds, etc)? (Consider soils and roots for optimal recovery) ContextFacts ISFM Progress Concl

48. Consortium for the improvement of agriculture- based livelihoods in Central Africa Conclusions

49. 1. Are cassava-based systems amenable to ‘full’ ISFM? • Most likely yes (All steps are potentially relevant for cassava-based systems, but substantial knowledge gaps exist) ContextFacts ISFM Progress Concl

50. 2. Is cassava an entry point for soil fertility rehabilitation? • Leaves contain a lot of nutrients; ‘N-sparing’ effects have been demonstrated for crops following cassava (This would only be valid if the cassava itself is showing a relatively high productivity) • In agronomic terms, cassava allows intercropping of various other crops, including legumes (These legumes could replenish the soil N stocks, improve the soil P status, etc) • It is unsure whether cassava would be a good crop on non-responsive plots that are being rehabilitated ContextFacts ISFM Progress Concl.