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Conservation agriculture in Southern Africa: Advances in knowledge

Published online by Cambridge University Press:  19 February 2014

Christian Thierfelder*
Affiliation:
International Maize and Wheat Improvement Centre (CIMMYT), P.O. Box MP163, Mount Pleasant, Harare, Zimbabwe.
Leonard Rusinamhodzi
Affiliation:
International Maize and Wheat Improvement Centre (CIMMYT), P.O. Box MP163, Mount Pleasant, Harare, Zimbabwe.
Amos R. Ngwira
Affiliation:
Department of International Environment and Development Studies, Noragric, University of Life Sciences, Aas, Norway.
Walter Mupangwa
Affiliation:
International Maize and Wheat Improvement Centre (CIMMYT), P.O. Box MP163, Mount Pleasant, Harare, Zimbabwe.
Isaiah Nyagumbo
Affiliation:
International Maize and Wheat Improvement Centre (CIMMYT), P.O. Box MP163, Mount Pleasant, Harare, Zimbabwe.
Girma T. Kassie
Affiliation:
International Maize and Wheat Improvement Centre (CIMMYT), P.O. Box MP163, Mount Pleasant, Harare, Zimbabwe. International Centre for Agricultural Research in the Dry Areas (ICARDA), Addis Ababa, Ethiopia.
Jill E. Cairns
Affiliation:
International Maize and Wheat Improvement Centre (CIMMYT), P.O. Box MP163, Mount Pleasant, Harare, Zimbabwe.
*
*Corresponding author: c.thierfelder@cgiar.org

Abstract

The increasing demand for food from limited available land, in light of declining soil fertility and future threats of climate variability and change have increased the need for more sustainable crop management systems. Conservation agriculture (CA) is based on the three principles of minimum soil disturbance, surface crop residue retention and crop rotations, and is one of the available options. In Southern Africa, CA has been intensively promoted for more than a decade to combat declining soil fertility and to stabilize crop yields. The objective of this review is to summarize recent advances in knowledge about the benefits of CA and highlight constraints to its widespread adoption within Southern Africa. Research results from Southern Africa showed that CA generally increased water infiltration, reduced soil erosion and run-off, thereby increasing available soil moisture and deeper drainage. Physical, chemical and biological soil parameters were also improved under CA in the medium to long term. CA increased crop productivity and also reduced on-farm labor, especially when direct seeding techniques and herbicides were used. As with other cropping systems, CA has constraints at both the field and farm level. Challenges to adoption in Southern Africa include the retention of sufficient crop residues, crop rotations, weed control, pest and diseases, farmer perception and economic limitations, including poorly developed markets. It was concluded that CA is not a ‘one-size-fits-all’ solution and often needs significant adaptation and flexibility when implementing it across farming systems. However, CA may potentially reduce future soil fertility decline, the effects of seasonal dry-spells and may have a large impact on food security and farmers’ livelihoods if the challenges can be overcome.

Type
Review Article
Copyright
Copyright © Cambridge University Press 2014 

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References

1 Rufino, M.C., Tittonell, P., van Wijk, M.T., Castellanos-Navarrete, A., Delve, R.J. and de Ridder, N. et al. 2007. Manure as a key resource within smallholder farming systems: Analysing farm-scale nutrient cycling efficiencies with the NUANCES framework. Livestock Science 112(3):273287.CrossRefGoogle Scholar
2 Tittonell, P., Scopel, E., Andrieu, N., Posthumus, H., Mapfumo, P., Corbeels, M., Van Halsema, G.E., Lahmar, R., Lugandu, S., Rakotoarisoa, J., Mtambanengwe, F., Pound, B., Chikowo, R., Naudin, K., Triomphe, B., and Mkomwa, S. 2012. Agroecology-based aggradation-1 conservation agriculture (ABACO): Targeting innovations to combat soil degradation and food insecurity in semi-arid. Africa Field Crop Research 132:168174.CrossRefGoogle Scholar
3 Pretty, J., Toulmin, C., and Williams, S. 2011. Sustainable intensification in African agriculture. International Journal of Agricultural Sustainability 9(1):524.CrossRefGoogle Scholar
4 Nyamapfene, K. 1991. Soils of Zimbabwe. Nehanda Publishers (Pvt) Ltd, Harare, Zimbabwe. p. 7579.Google Scholar
5 Nyamangara, J., Mugwira, L.M., and Mpofu, S.E. 2000. Soil fertility status in communal areas of Zimbabwe in relation to sustainable crop production. Journal of Sustainable Agriculture 16:1529.CrossRefGoogle Scholar
6 Edmeades, G., Chapman, S., and Lafitte, H. 1999. Selection improves drought tolerance in tropical maize populations: I. Gains in biomass, grain yield, and harvest index. Crop Science 39(5):13061315.CrossRefGoogle Scholar
7 Morris, M.L. 2007. Fertilizer use in African Agriculture: Lessons Learned and Good Practice Guidelines. World Bank Publications, Washington, DC.CrossRefGoogle Scholar
8 Kassie, G.T., Erenstein, O., Mwangi, W., LaRovere, R., Setimela, P., and Langyintuo, A. 2012. Characterization of Maize Production in Southern Africa: Synthesis of CIMMYT/DTMA Household Level Farming System Surveys in Angola, Malawi, Mozambique, Zambia and Zimbabwe. CIMMYT, El Batan, Mexico.Google Scholar
9 Sánchez, P.A. 2010. Tripling crop yields in tropical Africa. Nature Geoscience 3(5):299300.CrossRefGoogle Scholar
10 Okoth, P.F., Murua, E., Sanginga, N., Chianu, J., Mungatu, J.M., Kimani, P.K., and Ng'ang'a, J.K. 2011. Some Facts About Fertilizer Use in Africa: The Case of Smallholder and Large-Scale Farmers in Kenya. In Bationo, A., Waswa, B., Okeyo, J.M., Maina, F. and Kihara, J.M. (eds). Innovations as Key to the Green Revolution in Africa. Springer, Netherlands. p. 869878.CrossRefGoogle Scholar
11 Sanchez, P. 2002. Soil fertility and hunger in Africa. Science 295:20192020.CrossRefGoogle ScholarPubMed
12 World Bank. 2007. International Development Association on a Country Assistance Strategy of the World Bank for the Republic of Malawi. Washington, DC.Google Scholar
13 Thierfelder, C. and Wall, P.C. 2010. Rotations in conservation agriculture systems of Zambia: Effects on soil quality and water relations. Experimental Agriculture 46(3):309325.CrossRefGoogle Scholar
14 Waddington, S.R. 2003. Grain legumes and green manures for soil fertility in Southern Africa: Taking stock of progress. Proceedings of a conference held 8–11 October 2002 at the Leopard Rock Hotel, Vumba, Zimbabwe. Harare, Zimbabwe: SoilFertNet and CIMMYT-Zimbabwe. p. 1246.Google Scholar
15 World Bank. 2012. Fertilizer toolkit: Promoting efficient and sustainable fertilizer use. Why are fertilizer prices higher in Africa? Available at http://www.worldbank.org/html/extdr/fertilizeruse/bpractices/HighPrices.htm (accessed February 5, 2014).Google Scholar
16 Alvord, E.D. 1936. Sand veld farming and its possibilities. Rhodesia Agricultural Journal 15:11061110.Google Scholar
17 Andersson, J.A. and Giller, K.E. 2012. On heretics and God's blanket salesmen: Contested claims for conservation agriculture and the politics of its promotion in African smallholder farming. In Sumberg, J. and Thompson, J. (eds). Contested Agronomy: Agricultural Research in a Changing World. Earthscan, London. p. 122.Google Scholar
18 Lal, R. 2007. Constraints to adopting no-till farming in developing countries. Soil and Tillage Research 94:13.CrossRefGoogle Scholar
19 Montgomery, D.R. 2007. Dirt: The Erosion of Civilization. University of California Press, Berkley, California.CrossRefGoogle Scholar
20 Munyati, M. 1997. Conservation tillage for sustainable crop production systems: Results and experiences from on-station and on-farm research (1988–1996). Zimbabwe Science News 31(2):2733.Google Scholar
21 Elwell, H.A. and Stocking, M. 1988. Loss of soil nutrients by sheet erosion is a major hidden farming cost. Zimbabwe Science News 22:78.Google Scholar
22 Thierfelder, C., Amezquita, E., and Stahr, K. 2005. Effects of intensifying organic manuring and tillage practices on penetration resistance and infiltration rate. Soil and Tillage Research 82:211226.CrossRefGoogle Scholar
23 Thierfelder, C. and Wall, P.C. 2009. Effects of conservation agriculture techniques on infiltration and soil water content in Zambia and Zimbabwe. Soil and Tillage Research 105(2):217227.CrossRefGoogle Scholar
24 Rockström, J., Kaumbutho, P., Mwalley, J., Nzabi, A.W., Temesgen, M., Mawenya, L., Barron, J., Mutua, J., and Damgaard-Larsen, S. 2009. Conservation farming strategies in East and Southern Africa: Yields and rain water productivity from on-farm action research. Soil and Tillage Research 103(1):2332.CrossRefGoogle Scholar
25 Douglas, M. and Initiative, S.F. 1999. Malawi: An investigation into the presence of a cultivation hoe pan under smallholder farming conditions. Food and Agriculture Organization of the United States.Google Scholar
26 Materechera, S.A. and Mloza-Banda, H.R. 1997. Soil penetration resistance, root growth and yield of maize as influenced by tillage system on ridges in Malawi. Soil and Tillage Research 41:1324.CrossRefGoogle Scholar
27 Chivenge, P.P., Murwira, H.K., Giller, K.E., Mapfumo, P., and Six, J. 2007. Long-term impact of reduced tillage and residue management on soil carbon stabilization: Implications for conservation agriculture on contrasting soils. Soil and Tillage Research 94(2):328337.CrossRefGoogle Scholar
28 Ngwira, A.R., Thierfelder, C., and Lambert, D.M. 2012. Conservation agriculture systems for Malawian smallholder farmers: Long-term effects on crop productivity profitability, and soil quality. Renewable Agriculture and Food Systems 1(1): 114.Google Scholar
29 Govaerts, B., Verhulst, N., Castellanos-Navarrete, A., Sayre, K.D., Dixon, J., and Dendooven, L. 2009. Conservation agriculture and soil carbon sequestration: Between myth and farmer reality. Critical Reviews in Plant Sciences 28(3):97122.CrossRefGoogle Scholar
30 Thierfelder, C. and Wall, P.C. 2012. Effects of conservation agriculture on soil quality and productivity in contrasting agro-ecological environments of Zimbabwe. Soil Use and Management 28(2):209220.CrossRefGoogle Scholar
31 McDowell, L. and McGregor, K. 1980. Nitrogen and phosphorus losses in runoff from no-till soybeans. Transactions of the ASAE 23(3):643648.CrossRefGoogle Scholar
32 Gilbert, N. 2012. Dirt poor: The key to tackling hunger in Africa is enriching its soil. The big debate is about how to do it. Nature 483:525527.CrossRefGoogle Scholar
33 Sumberg, J. and Thompson, J. 2012. Contested Agronomy: Agricultural Research in a Changing World. Earthscan, London.CrossRefGoogle Scholar
34 Garrity, D., Akinnifesi, F., Ajayi, O., Sileshi, G.W., Mowo, J.G., Kalinganire, A., Larwanou, M., and Bayala, J. 2010. Evergreen Agriculture: A robust approach to sustainable food security in Africa. Food Security 2(3):197214.CrossRefGoogle Scholar
35 Verhulst, N., Govaerts, B., Verachtert, E., Castellanos-Navarrete, A., Mezzalama, M., Wall, P., Deckers, J., and Sayre, K.D. 2010. Conservation agriculture, improving soil quality for sustainable production systems. In Lal, R. and Stewart, B.A. (eds). Advances in Soil Science: Food Security and Soil Quality. CRC Press, Boca Raton, FL. p. 137208.CrossRefGoogle Scholar
36 Wall, P.C. 2007. Tailoring Conservation Agriculture to the needs of small farmers in developing countries: An analysis of issues. Journal of Crop Improvement 19(1/2):137155.CrossRefGoogle Scholar
37 Valbuena, D., Erenstein, O., Homann-Kee, Tui S., Abdoulaye, T., Claessens, L., Duncan, A.J., Gérard, B., Rufino, M.C., Teufel, N., van Rooyen, A., and van Wijk, M.T. 2012. Conservation Agriculture in mixed crop–livestock systems: Scoping crop residue trade-offs in Sub-Saharan Africa and South Asia. Field Crops Research 132:175184.CrossRefGoogle Scholar
38 Kassam, A., Friedrich, T., Shaxson, F., and Pretty, J. 2009. The spread of conservation agriculture: justification, sustainability and uptake. International Journal of Agricultural Sustainability 7(4):292320.CrossRefGoogle Scholar
39 Evenson, R.E. and Gollin, D. 2003. Crop Variety Improvement and its Effect on Productivity: The Impact of International Agricultural Research. CABI, Wallingford, UK.Google Scholar
40 Evenson, R.E. and Gollin, D. 2003. Assessing the impact of the Green Revolution, 1960 to 2000. Science 300(5620):758762.CrossRefGoogle ScholarPubMed
41 Hobbs, P.R. 2007. Conservation agriculture: what is it and why is it important for future sustainable food production? Journal of Agricultural Science 145:127137.CrossRefGoogle Scholar
42 Erenstein, O., Sayre, K., Wall, P., Hellin, J., and Dixon, J. 2012. Conservation agriculture in maize- and wheat-based systems in the (sub)tropics: Lessons from adaptation initiatives in South Asia, Mexico, and Southern Africa. Journal of Sustainable Agriculture 36(2):180206.CrossRefGoogle Scholar
43 Bolliger, A., Magid, J., Amado, T.J.C., Scora, Neto F., Dos, Santos Ribeiro M.D.F., Calegari, A., Ralisch, R., and De Neergaard, A. 2006. Taking stock of the Brazilian ‘zero-till revolution’: a review of landmark research an farmers’ practice. Advances in Agronomy 91:47110.CrossRefGoogle Scholar
44 Derpsch, R. 2002. Making conservation tillage conventional, building a future on 25 years of research: research and extension perspective. In van Santen, E. (ed.). Proceedings of 25th Annual Southern Conservation Tillage Conference for Sustainable Agriculture, Auburn, AL, USA, 24–26 June, 2002. p. 25–9.Google Scholar
45 Derpsch, R., Florentin, M.A., and Moriya, K. 2000. Importancia de la Siembra Directa Para Alcanzar La Sustenabilidad Agrócola. Publicación del Proyecto Conservación de Suelo MAG-GTZ, San Lorenzo, Paraguay. p. 140.Google Scholar
46 Lal, R., Reicosky, D.C., and Hanson, J.D. 2007. Evolution of the plow over 10,000 years and the rationale for no-till farming. Soil and Tillage Research 93(1):112.CrossRefGoogle Scholar
47 Reicosky, D.C. and Allmaras, R.R. 2003. Advances in tillage research in North American cropping systems. Journal of Crop Production 8(1–2):75125.CrossRefGoogle Scholar
48 Friedrich, T., Derpsch, R. and Kassam, A. 2012. Overview of the global spread of conservation agriculture. Field Actions Science Reports, Special Issue. 6. Available at http://factsreports.revues.org/1941 (accessed February 5, 2014).Google Scholar
49 Benites, J., Chuma, E., Fowler, R., Kienzle, J., Molapong, K., Manu, J., Nyagumbo, I., Steiner, K., and Van Veenhuizen, R. (eds). 1998. Conservation tillage for sustainable agriculture. International Workshop Harare, Proceedings Part I (Workshop Report), Rome: FAO with GTZ, ZFU, FARMESA and ARC.Google Scholar
50 Bolliger, A. 2007. Is zero-till an appropriate agricultural alternative for disadvantaged smallholders of South Africa? A study of surrogate systems and strategies, smallholder sensitivities and soil glycoproteins. PhD Thesis, University of Copenhagen.Google Scholar
51 Giller, K.E., Witter, E., Corbeels, M., and Tittonell, P. 2009. Conservation agriculture and smallholder farming in Africa: The heretic's view. Field Crops Research 114:2334.CrossRefGoogle Scholar
53 Giller, K.E. 2012. No silver bullets for African soil problems. Nature 485:41.CrossRefGoogle ScholarPubMed
54 Buffet, H.W. 2012. Reaping the benefits of no-tillage farming. Nature 484:455.CrossRefGoogle Scholar
55 Kassam, A. and Brammer, H. 2013. Reply to Sumberg et al. The Geographical Journal 179(2):186–7.CrossRefGoogle Scholar
56 Tittonell, P., Muriuki, A., Shepherd, K.D., Mugendi, D., Kaizzi, K.C., Okeyo, J., Verchot, L., Coe, R., and Vanlauwe, B. 2010. The diversity of rural livelihoods and their influence on soil fertility in agricultural systems of East Africa – A typology of smallholder farms. Agricultural Systems 103(2):8397.CrossRefGoogle Scholar
57 Tittonell, P., Vanlauwe, B., de Ridder, N., and Giller, K.E. 2007. Heterogeneity of crop productivity and resource use efficiency within smallholder Kenyan farms: Soil fertility gradients or management intensity gradients? Agricultural Systems 94(2):376390.CrossRefGoogle Scholar
58 Vogel, H. 1994. Conservation Tillage in Zimbabwe: Evaluation of Several Techniques for the Development of Sustainable Crop Production Systems in Smallholder Farming [African Studies Series A11]. University of Berne, Switzerland.Google Scholar
59 Nyagumbo, I. 2002. The effects of three tillage systems on seasonal water budgets and drainage of two Zimbabwean soils under maize. Dphil Thesis, University of Zimbabwe, Harare, Zimbabwe.Google Scholar
60 Vogel, H., Nyagumbo, I., and Olsen, K. 1994. Effects of tied ridging and mulch ripping on water conservation in maize production on sandveld soils. Der Tropenlandwirt Journal of Agriculture in the Tropics and Subtropics 3–4:3344.Google Scholar
61 Nyagumbo, I. 2008. A review of experiences and developments towards Conservation Agriculture and related systems in Zimbabwe. In Goddard, T., Zoebisch, M.A., Gan, Y.T., Ellis, W., Watson, A. and Sombatpanit, S., (eds). No-Till Farming Systems. World Association of Soil and Water Conservation, Bangkok, Thailand, Special publication No. 3. p. 345372.Google Scholar
62 Oldrieve, B. 1993. Conservation Farming for Communal, Small Scale, Resettlement and Co-Operative Farmers of Zimbabwe: A Farm Management Handbook. Prestige Business Services (Pvt) Ltd, Harare, Zimbabwe.Google Scholar
63 Mupangwa, W., Walker, S., and Twomlow, S. 2011. Start, end and dry spells of the growing season in semi-arid southern Zimbabwe. Journal of Arid Environments 75(11):10971104.CrossRefGoogle Scholar
64 Usman, M.T. and Reason, C. 2004. Dry spell frequencies and their variability over Southern Africa. Climate Research 26(3):199211.CrossRefGoogle Scholar
65 Mupangwa, W., Twomlow, S., and Walker, S. 2013. Cumulative effects of reduced tillage and mulching on soil properties under semi-arid conditions. Journal of Arid Environments 91:4552.CrossRefGoogle Scholar
66 Mupangwa, W. and Jewitt, G. 2011. Simulating the impact of no-till systems on field water fluxes and maize productivity under semi-arid conditions. Physics and Chemistry of the Earth, Parts A/B/C 36(14):10041011.CrossRefGoogle Scholar
67 Nyamadzawo, G., Nyamangara, J., Nyamugafata, P., and Muzulu, A. 2009. Soil microbial biomass and mineralization of aggregate protected carbon in fallow-maize systems under conventional and no-tillage in Central Zimbabwe. Soil and Tillage Research 102(1):151157.CrossRefGoogle Scholar
68 Mupangwa, W., Twomlow, S., and Walker, S. 2012. Reduced tillage, mulching and rotational effects on maize (Zea mays L.), cowpea (Vigna unguiculata (Walp) L.) and sorghum (Sorghum bicolor L. (Moench)) yields under semi-arid conditions. Field Crops Research 132:139148.CrossRefGoogle Scholar
69 Baldock, J.A. and Nelson, P.N. 2000. Soil Organic Matter. Handbook of Soil Science. CRC Press, Boca Raton, FL. p. 2584.Google Scholar
70 Valentin, C. 1991. Surface crusting in two alluvial soils of northern Niger. Geoderma 48:201222.CrossRefGoogle Scholar
71 McGarry, D. 2003. Tillage and soil compaction. In Garcia-Torres, L., Benites, J., Martinez-Vilela, A. and Holgado-Cabrera, A. (eds). Conservation Agriculture. Kluwer Academic Publishers, Dordrecht. p. 307316.CrossRefGoogle Scholar
72 Oicha, T., Cornelis, W.M., Verplancke, H., Nyssen, J., Govaerts, B., Behailu, M., Haile, M., and Deckers, J. 2010. Short-term effects of conservation agriculture on Vertisols under tef (Eragrostis tef (Zucc.) Trotter) in the northern Ethiopian highlands. Soil and Tillage Research 106(2):294302.CrossRefGoogle Scholar
73 Thierfelder, C., Cheesman, S., and Rusinamhodzi, L. 2012. A comparative analysis of conservation agriculture systems: Benefits and challenges of rotations and intercropping in Zimbabwe. Field Crops Research 137:237250.CrossRefGoogle Scholar
74 Nhamo, N. 2007. The contribution of different fauna communities to improved soil health: a case of Zimbabwean soils under conservation agriculture. PhD Thesis, Rheinischen Friedrich-Wilhelms-Universitat, Bonn, Germany. p. 128.Google Scholar
75 Mutema, M., Mafongoya, P.L., Nyagumbo, I., and Chakukura, L. 2013. Effects of crop residues and reduced tillage on macrofauna abundance. Journal of Organic Systems 8(1):516.Google Scholar
76 Kladviko, E.J., Mackay, A.D., and Bradford, J.M. 1986. Earthworms as a factor in the reduction of soil crusting. Soil Science Society of America Journal 50:191196.CrossRefGoogle Scholar
77 Ehlers, W. 1975. Observations on earthworm channels and infiltration on tilled and untilled Loess soils. Soil Science 119:7377.CrossRefGoogle Scholar
78 Ngwira, A., Sleutel, S., and De Neve, S. 2012. Soil carbon dynamics as influenced by tillage and crop residue management in loamy sand and sandy loam soils under smallholder farmers’ conditions in Malawi. Nutrient Cycling in Agroecosystems 92(3):315328.CrossRefGoogle Scholar
79 Mazvimavi, K., Twomlow, S., Belder, P., and Hove, L. 2008. An assessment of the sustainable uptake of conservation farming in Zimbabwe. Global Theme on Agroecosystems Report no. 39. International Crops Research Institute for the Semi-Arid Tropics, Bulawayo, Zimbabwe.Google Scholar
80 Nyamangara, J., Masvaya, E.N., Tirivavi, R., and Nyengerai, K. 2013. Effect of hand-hoe based conservation agriculture on soil fertility and maize yield in selected smallholder areas in Zimbabwe. Soil and Tillage Research 126:1925.CrossRefGoogle Scholar
81 Rusinamhodzi, L., Corbeels, M., Nyamangara, J., and Giller, K.E. 2012. Maize–grain legume intercropping is an attractive option for ecological intensification that reduces climatic risk for smallholder farmers in central Mozambique. Field Crops Research 136:1222.CrossRefGoogle Scholar
82 Jordan, V.W.L. and Hutcheon, J.A. 2003. Influence of cultivation practices on arable crop diseases. In Titi, A.E. (ed). Soil Tillage in Agroecosystems. CRC Press, Boca Raton, FL.Google Scholar
83 Kanampiu, F.K., Kabambe, V., Massawe, C., Jasi, L., Friesen, D., Ransom, J.K., and Gressel, J. 2003. Multi-site, multi-season field tests demonstrate that herbicide seed-coating herbicide-resistance maize controls Striga spp. and increases yields in several African countries. Crop Protection 22(5):697706.CrossRefGoogle Scholar
84 Mloza-Banda, H.R. and Kabambe, V.H. 1997. Integrated management of striga control in Malawi. African Crop Science Journal 5(2):263273.Google Scholar
85 Vanlauwe, B., Kanampiu, F., Odhiambo, G.D., De Groote, H., Wadhams, L.J., and Khan, Z.R. 2008. Integrated management of Striga hermonthica, stemborers, and declining soil fertility in western Kenya. Field Crops Research 107(2):102115.CrossRefGoogle Scholar
86 Thierfelder, C., Chisui, J.L., Gama, M., Cheesman, S., Jere, Z.D., Bunderson, W.T., Ngwira, A.R., and Eash, N.S. 2013. Maize-based conservation agriculture systems in Malawi: Long-term trends in productivity. Field Crop Research 142:4757.CrossRefGoogle Scholar
87 Sturz, A.V., Carter, M.R., and Johnston, H.W. 1997. A review of plant disease, pathogen interactions and microbial antagonism under conservation tillage in temperate humid agriculture. Soil and Tillage Research 41(3–4):169189.CrossRefGoogle Scholar
88 Cairns, J.E., Sonder, K., Zaidi, P.H., Verhulst, N., Mahuku, G., Babu, R., Nair, S.K., Das, B., Govaerts, B., Vinayan, M.T., Rashid, Z., Noor, J.J., Devi, P., San, Vicente F., and Prasanna, B.M. 2012. Maize production in a changing climate: Impacts, adaptation, and mitigation strategies. In Sparks, D. (ed). Advances in Agronomy. Academic Press, Burlington. p. 158.Google Scholar
89 Meisel, B., Korsman, J., Kloppers, F., and Berger, D. 2009. Cercospora zeina is the causal agent of grey leaf spot disease of maize in Southern Africa. European Journal of Plant Pathology 124(4):577583.CrossRefGoogle Scholar
90 Ward, J.M.J., Laing, M.D., and Cairns, A.L.P. 1997. Management practices to reduce gray leaf spot of maize. Crop Science 37(4):12571262.CrossRefGoogle Scholar
91 Payne, G. 1987. Aspergillus flavus infection of maize: silks and kernels. US Universities-CIMMYT Maize Aflatoxin Workshop, El Batan, Mexico (Mexico), April 7–11, 1987. CIMMYT, Mexico, DF (Mexico). p. 119129.Google Scholar
92 Savary, S., Nelson, A., Sparks, A.H., Willocquet, L., Duveiller, E., Mahuku, G., Forbes, G., Garrett, K.A., Hodson, D., Padgham, J., Pande, S., Sharma, M., Yuen, J., and Djurle, A. 2011. International agricultural research tackling the effects of global and climate changes on plant diseases in the developing world. Plant Disease 95:12.CrossRefGoogle ScholarPubMed
93 Lipps, P.E. and Deep, I.W. 1991. Influence of tillage and crop rotation on yield, stalk rot, and recovery of Fusarium and Trichoderma spp. from corn. Plant Disease 75(8):5.CrossRefGoogle Scholar
94 Thierfelder, C., Cheesman, S., and Rusinamhodzi, L. 2012. Benefits and challenges of crop rotations in maize-based conservation agriculture (CA) cropping systems of Southern Africa. International Journal of Agricultural Sustainability 11(2):108124.CrossRefGoogle Scholar
95 Thierfelder, C., Mombeyarara, T., Mango, N., and Rusinamhodzi, L. 2013. Integration of conservation agriculture in smallholder farming systems of Southern Africa: identification of key entry points. International Journal of Agricultural Sustainability 11(4):317330.CrossRefGoogle Scholar
96 Rusinamhodzi, L., Corbeels, M., van Wijk, M., Rufino, M., Nyamangara, J., and Giller, K. 2011. A meta-analysis of long-term effects of conservation agriculture on maize grain yield under rain-fed conditions. Agronomy for Sustainable Development 31(4):657673.CrossRefGoogle Scholar
97 Thierfelder, C., Mwila, M., and Rusinamhodzi, L. 2013. Conservation agriculture in eastern and southern provinces of Zambia: Long-term effects on soil quality and maize productivity. Soil and Tillage Research 126:246258.CrossRefGoogle Scholar
98 Cocks, P. 2001. Ecology of herbaceous perennial legumes: a review of characteristics that may provide management options for the control of salinity and waterlogging in dryland cropping systems. Crop and Pasture Science 52(2):137151.CrossRefGoogle Scholar
99 Mazvimavi, K. 2011. Socio-Economic Analysis of Conservation Agriculture in Southern Africa. Food and Agricultural Organization of the United Nations (FAO), Regional Emergency Office for Southern Africa (REOSA), Johannesburg, South Africa. Network paper 02, January 2011.Google Scholar
100 Mazvimavi, K., Twomlow, S., Murendo, C., and Musitini, T. 2007. Science in agricultural relief and development programs: The case of conservation farming in Zimbabwe. AAAE Conference Proceedings. p. 321325.Google Scholar
101 Mazvimavi, K. and Twomlow, S. 2009. Socioeconomic and institutional factors influencing adoption of conservation agriculture by vulnerable households in Zimbabwe. Agricultural Systems 101:2029.CrossRefGoogle Scholar
102 Ngwira, A.R., Aune, J.B., and Mkwinda, S. 2012. On-farm evaluation of yield and economic benefit of short term maize legume intercropping systems under conservation agriculture in Malawi. Field Crops Research 132:149157.CrossRefGoogle Scholar
103 Johansen, C., Haque, M.E., Bell, R.W., Thierfelder, C., and Esdaile, R.J. 2012. Conservation agriculture for small holder rainfed farming: Opportunities and constraints of new mechanized seeding systems. Field Crops Research 132:1832.CrossRefGoogle Scholar
104 Twomlow, S., Hove, L., Mupangwa, W., Masikati, P., and Mashingaidze, N. 2008. Precision conservation agriculture for vulnerable farmers in low-potential zones. In Humphrey, E. and Bayot, R.S. (eds). Increasing the productivity and sustainability of rainfed cropping systems for poor smallholder farmers Proceedings of the CGIAR Challenge Program on Water and Food International Workshop on Rainfed Cropping Systems, Tamale, Ghana, September 22–25, 2008. p. 37.Google Scholar
105 Umar, B.B., Aune, J.B., Johnsen, F.H., and Lungu, I.O. 2012. Are smallholder Zambian farmers economists? A dual-analysis of farmers’ expenditure in conservation and conventional agriculture systems. Journal of Sustainable Agriculture 36(8):908929.CrossRefGoogle Scholar
106 Haggblade, S. and Tembo, G. 2003. Conservation farming in Zambia. EPTD Discussion Paper No. 108. IFPRI, Washington DC. p. 1112.Google Scholar
107 Siziba, S. 2007. Assessing the adoption of conservation agriculture in Zimbabwe's smallholder sector. PhD thesis, University of Hohenheim, Hohenheim.Google Scholar
108 Ito, M., Matsumoto, T., and Quinones, M.A. 2007. Conservation tillage practices in sub-Saharan Africa: The experience of Sassakawa Global 2000. Crop Protection 26:417423.CrossRefGoogle Scholar
109 Muoni, T., Rusinamhodzi, L., and Thierfelder, C. 2013. Weed control in conservation agriculture systems of Zimbabwe: identifying economical best strategies. Crop Protection 53:2328.CrossRefGoogle Scholar
110 Pampel, F. and van Es, J. 1977. Environmental quality and issues of adoption research. Rural Sociology 42(1):5771.Google Scholar
111 Stonehouse, D.P. 1995. Profitability of soil and water conservation in Canada: A review. Journal of Soil and Water Conservation 50(2):215219.Google Scholar
112 Ngwira, A.R., Thierfelder, C., Eash, N., and Lambert, D.M. 2013. Risk and maize-based cropping systems for smallholder Malawi farmers using conservation agriculture technologies. Experimental Agriculture FirstView 121.Google Scholar
113 Mashingaidze, N., Madakadze, C., Twomlow, S., Nyamangara, J., and Hove, L. 2012. Crop yield and weed growth under conservation agriculture in semi-arid Zimbabwe. Soil and Tillage Research 124:102110.CrossRefGoogle Scholar
114 Ngwira, R.A., Thierfelder, C., Eash, N.S., and Lambert, D.M. 2013. Risk and maize-based cropping systems for smallholder Malawi farmers using conservation agriculture technologies. Experimental Agriculture 49(4):483503.CrossRefGoogle Scholar
115 Mazvimavi, K., Ndlovu, P.V., Nyathi, P., and Minde, I.J. 2010. Conservation Agriculture Practices and Adoption by Smallholder Farmers in Zimbabwe. Cape Town, South Africa, September 19–23, 2010: Poster presented at the Joint 3rd African Association of Agricultural Economists (AAAE) and 48th Agricultural Economists Association of South Africa (AEASA) Conference.Google Scholar
116 Mazvimavi, K., Ndlovu, P.V., Nyagumbo, I., and Dimes, J.P. 2009. Trends in adoption of conservation farming practices among smallholder farmers in Zimbabwe. Report No. 38. International Crops Research Institute for the Semi-Arid Tropics, Bulawayo, Zimbabwe.Google Scholar
117 Romney, D.L., Thorne, P., Lukuyu, B., and Thornton, P.K. 2003. Maize as food and feed in intensive smallholder systems: management options for improved integration in mixed farming systems of east and southern Africa. Field Crops Research 84(1–2):159168.CrossRefGoogle Scholar
118 Seo, S.N. 2010. Is an integrated farm more resilient against climate change? A micro-econometric analysis of portfolio diversification in African agriculture. Food Policy 35(1):3240.CrossRefGoogle Scholar
119 Shumba, E.M., Wallgren, V.L., Carlson, A., Kuona, M., and Moyo, N. 2012. Community Climate Change Vulnerability Assessment in Miombo Woodlands Harare. World Wide Fund for Nature, Eco-Region Programme, Zimbabwe.Google Scholar
120 Van Duivenbooden, N., Pala, M., Studer, C., Bielders, C.L., and Beukes, D.J. 2000. Cropping systems and crop complementarity in dryland agriculture to increase soil water use efficiency: A review. Netherlands Journal of Agricultural Science 48:213236.Google Scholar
121 Njarui, D.M.G. and Mureithi, J.G. 2010. Evaluation of lablab and velvet bean fallows in a maize production system for improved livestock feed supply in semiarid tropical Kenya. Animal Production Science 50(3):193202.CrossRefGoogle Scholar
122 Rusinamhodzi, L., Corbeels, M., Zingore, S., Nyamangara, J., and Giller, K.E. 2013. Pushing the envelope? Maize production intensification and the role of cattle manure in recovery of degraded soils in smallholder farming areas of Zimbabwe. Field Crops Research 147:4053.CrossRefGoogle Scholar
123 Nyagumbo, I. 2011. Exploring crop yield benefits of integrated water and nutrient management technologies in the Desert Margins of Africa: Experiences from semi-arid Zimbabwe. Vol. 1. Journal of Agricultural Science and Technology 3:401414.Google Scholar
124 Rufino, M.C., Rowe, E.C., Delve, R.J., and Giller, K.E. 2006. Nitrogen cycling efficiencies through resource-poor African crop-livestock systems. Agriculture, Ecosystems and Environment 112(4):261282.CrossRefGoogle Scholar
125 Sumberg, J. 2002. The logic of fodder legumes in Africa. Food Policy 27(3):285300.CrossRefGoogle Scholar
126 Rufino, M.C., Dury, J., Tittonell, P., van Wijk, M.T., Herrero, M., Zingore, S., Mapfumo, P., and Giller, K.E. 2011. Competing use of organic resources, village-level interactions between farm types and climate variability in a communal area of NE Zimbabwe. Agricultural Systems 104(2):175190.CrossRefGoogle Scholar
127 Delve, R.J., Cadisch, G., Tanner, J.C., Thorpe, W., Thorne, P.J., and Giller, K.E. 2001. Implications of livestock feeding management on soil fertility in the smallholder farming systems of sub-Saharan Africa. Agriculture, Ecosystems and Environment 84(3):227243.CrossRefGoogle Scholar
128 Snapp, S.S., Blackie, M.J., Gilbert, R.A., Bezner-Kerr, R., and Kanyama-Phiri, Y. 2010. Biodiversity can support a greener revolution in Africa. Proceedings of the National Academy of Sciences of the United States of America 107(48):2084020845.CrossRefGoogle ScholarPubMed
129 Snapp, S.S., Rohrbach, D.D., Simtowe, F., and Freema, H.A. 2002. Sustainable soil management options for Malawi: Can smallholder grow more legumes? Agriculture, Ecosystems and Environment 91:159174.CrossRefGoogle Scholar
130 Sakala, W.D. 1994. Crop management interventions in traditional maize pigeonpea intercropping systems in Malawi. MSc thesis, University of Malawi.Google Scholar
131 Shumba, E., Dhilwayo, H., and Mukoko, O. 1990. The potential of maize-cowpea intercropping in low rainfall areas of Zimbabwe. Zimbabwe Journal of Agricultural Research 28:3338.Google Scholar
132 Waddington, S.R., Mekuria, M., Siziba, S., and Karigwindi, J. 2007. Long-term yield sustainability and financial returns from grain legume-maize intercrops on a sandy soil in subhumid north central Zimbabwe. Experimental Agriculture 43(4):489503.CrossRefGoogle Scholar
133 Rusinamhodzi, L., Murwira, H.K., and Nyamangara, J. 2006. Cotton-cowpea intercropping and its N2 fixation capacity improves yield of a subsequent maize crop under Zimbabwean rain-fed conditions. Plant and Soil 287(1–2):327336.CrossRefGoogle Scholar
134 Giller, K.E. 2001. Nitrogen Fixation in Tropical Cropping Systems. CABI Publishing, New York.CrossRefGoogle Scholar
135 Graham, P.H. and Vance, C.P. 2003. Legumes: Importance and constraints to greater use. Plant Physiology 131(3):872877.CrossRefGoogle ScholarPubMed
136 Chauhan, B.S., Gill, G.S., and Preston, C. 2006. Tillage system effects on weed ecology, herbicide activity and persistence: A review. Animal Production Science 46(12):15571570.CrossRefGoogle Scholar
137 Vogel, H. 1994. Weeds in single-crop conservation farming in Zimbabwe. Soil and Tillage Research 31:169185.CrossRefGoogle Scholar
138 Vogel, H. 1995. The need for integrated weed management systems in smallholder conservation farming in Zimbabwe. Der Tropenlandwirt 96:3556.Google Scholar
139 Rahman, A., James, T.K., and Grbavac, N. 2001. Potential of weed seedbanks for managing weeds: a review of recent New Zealand research. Weed Biology and Management 1(2):8995.CrossRefGoogle Scholar
140 Mwale, C. 2009. Effect of tillage practices on weed populations and seed banks in maize based production systems in Malawi. Masters thesis, ISARA-Lyon, University of Lyon.Google Scholar
141 Gowing, J.W. and Palmer, M. 2008. Sustainable agricultural development in sub-Saharan Africa: the case for a paradigm shift in land husbandry. Soil Use and Management 24(1):9299.CrossRefGoogle Scholar
142 Flower, K.C., Cordingley, N., Ward, P.R., and Weeks, C. 2012. Nitrogen, weed management and economics with cover crops in conservation agriculture in a Mediterranean climate. Field Crops Research 132:6375.CrossRefGoogle Scholar
143 Caamal-Maldonado, J.A., Jiménez-Osornio, J.J., Torres-Barragán, A., and Anaya, A.L. 2001. The use of allelopathic legume cover and mulch species for weed control in cropping systems. Agronomy Journal 93(1):2736.CrossRefGoogle Scholar
144 Kassie, G.T., Erenstein, O., Mwangi, W., MacRobert, J., Setimela, P., and Shiferaw, B. 2013. Political and economic features of the maize seed industry in Southern Africa. Agrekon: Agricultural Economics Research, Policy and Practice in Southern Africa 52(2):104127.CrossRefGoogle Scholar
145 Ndah, H.T., Schuler, J., Uthes, S., Zander, P., Triomphe, B., Apina, T., and Corbeels, M. (eds.) 2011. A Qualitative Expert Assessment Tool for Conservation Agriculture (QAToCA): assessing the adoption of conservation agriculture in Africa. Conference on International Research on Food Security, Natural Resource Management and Rural Development, University of Bonn, Bonn, Germany.Google Scholar
146 Ndah, H.T., Schuler, J., Uthes, S., Zander, P., Traore, K., Gama, M., Nyagumbo, I., Triomphe, B., and Corbeels, M. 2013. Adoption potential of adapted Conservation Agriculture practices in Sub-Saharan Africa: results from five case studies. Enviromental Management (Epub ahead of print).Google ScholarPubMed
147 Sims, B.G., Thierfelder, C., Kienzle, J., Friedrich, T., and Kassam, A. 2012. Development of the conservation agriculture equipment industry in sub-Saharan Africa. Applied Engineering in Agriculture 28:813823 CrossRefGoogle Scholar