Maize legume relay intercrops in Malawi - Microbial Ecology in Sustainable Agroecosystems - page 226

chapter 9
Maize legume relay intercrops in Malawi
Meeting short- and long-term
sustainability goals
Carol Shennan
University of California, Santa Cruz
Dorothy Sirrine
University of California, Santa Cruz
and Utopia Foundation, Traverse City
Contents
9.1 Introduction ........................................................................................................................ 230
9.2 Improving soil fertility in sub-Saharan Africa.............................................................. 231
9.3 Legume-based systems ..................................................................................................... 232
9.4 A conceptual framework for assessing relative sustainability of production
systems ................................................................................................................................ 235
9.4.1 The importance of the time dimension .............................................................. 236
9.4.2 Socioeconomic variability, vulnerability, and distributional impacts ........... 237
9.5 Case study: legume maize relay cropping in Southern Malawi................................. 238
9.5.1 Study location and farmer selection ................................................................... 238
9.5.2 Legume species ...................................................................................................... 239
9.5.3 Experimental design and management.............................................................. 239
9.5.4 Maize yields............................................................................................................ 241
9.5.5 Soil analysis ............................................................................................................ 241
9.5.6 Maize foliar analysis ............................................................................................. 241
9.5.7 Legume biomass and tissue analysis.................................................................. 242
9.5.8 Economic analysis.................................................................................................. 242
9.5.9 Socioeconomic data collection and analysis ...................................................... 243
9.6 Case study results and discussion .................................................................................. 243
9.7 Legume yields and N input ............................................................................................. 246
9.7.1 Soil fertility ............................................................................................................. 249
9.7.2 Distributional economic analysis ........................................................................ 251
9.7.3 Legume system adoption and preference .......................................................... 252
9.8 Assessing sustainability ................................................................................................... 254
9.9 Conclusion .......................................................................................................................... 258
References..................................................................................................................................... 259
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