Grain legume production and their potential for sustainable agriculture in Botswana between 2008 and 2015: a review

Abstract

Pulse crops are an integral component of arable agriculture in Botswana, particularly in subsistence farming. The benefits of these crops include provision of nutrition for both human beings and livestock, as well as environmental sustainability needs. Although they have a far reaching socio-economic impact, these benefits have not been adequately characterized for inclusion in endeavors of conservation agriculture in the country. Furthermore, data on pulses are often lumped together without identifying important pulse crops grown in Botswana. The objective of this paper was to review production of pulses and their potential as components in cropping systems and conservation agriculture in Botswana. The data used in this study were obtained from reports of Ministry of Agriculture and Food Security (MOA), Statistics Botswana, FAOSTAT and other literature sources. With the ongoing changes in climate and predicted increase in incidences of drought, pulses are among crops most relevant to sustainable agriculture. They are among the most versatile because of their variability in cropping duration from early to late maturity. Their consumption ranges from fresh forms to physiologically mature grain.  Pulses play an important role in climate change mitigation through their ability to fix nitrogen, thus reducing dependency on organic and synthetic fertilizers. They use less water from relatively shallow soil and allow for stratified soil water use for companion crops in intercropping or conserve soil water for subsequent crops in rotations. Thus pulses improve both water and nutrient use efficiencies when included in cropping systems. Their production also has a low footprint in both carbon and water. Currently, pulses are among the few highly priced crops in Botswana markets and together with the possibility of replacement of imported grain, investments in their production can generate income and improve livelihood of both farmers and consumers in Botswana. Crop production management technology involves judicious use of integrated nutrient, pest and disease management; appropriate integrated management packages that include pulses can be promoted to ensure sustainable crop production under the adverse impacts of climate change.