For further information contact: Peter Okoth

TSBF-CIAT's new strategy will emphasize developing and extending technologies that support sustainable intensification of cropping systems, especially in the dry and moist savanna and hillside agro-ecological zones (AEZs) in Africa and Latin America. In these AEZs, poverty, population growth and a rising demand for food increases pressure on marginal lands and/or remnant forest zones. This is accompanied by a shift towards shorter fallow periods and even continuous cropping. The strategic choice of pursuing sustainable intensification in these AEZs is based on three additional factors. First, large areas in Africa and Central America have already made the transition from crop-fallow to continuous cropping systems, a trend that is likely to accelerate. Second, under low soil fertility conditions, improved germplasm alone is not likely to achieve the required rates of improvements in food production, income, and natural resource conservation. Third, use of inputs to maintain soil fertility and improved germplasm have not been widely adopted, while disease outbreaks and increased pest pressure, especially from weeds and parasites like Striga, are often associated with intensification.

The most promising solution to achieving food security and protecting against natural resource degradation lies in sustainable intensification of agriculture on existing cropland. An issue is why existing technologies known to increase yields substantially have not been widely adopted by farmers in these regions, where cropping intensity is increasing and new crops are expanding in production area. The paradigmatic shift described in our strategy and work plan, designed to dig deeper into the constraints to realizing ISFM, will be operationalized through a combination of biophysical interventions and improved understanding of the socio-cultural and economic context.

Using participatory and conventional research methods, new and better adapted technology-based interventions (resilient germplasm and integrated fertilizer management schemes) will be tailored to the target AEZs.

In this strategy, the entry point for the management of the natural resource base for agriculture will be at the soils level. At the heart of this agenda are traditional elements of increasing nutrient and water use-efficiency and building long-term fertility through increasing soil nutrients and organic matter. These interventions will be integrated with management of water, pests and other elements of above- and below-ground biodiversity. However, we also believe that improved crop, forage and fallow germplasm constitutes a key entry point. Adapting improved germplasm to soil problems can lead to resilient and sustainable cropping systems, thereby serving as a starting point for the transformation of smallholder farmers from subsistence to market-oriented agriculture. Integration of livestock in these cropping systems also features prominently in the strategy, to increase and diversify income sources and to promote recycling of nutrients. These technology-based interventions will be meshed with biophysical simulation models and will build on the existing capacity of farmers, using a range of participatory techniques to take account of socio-cultural and economic dynamics both at the farm level and in the broader economic and policy domain.

Fertilizer Research for Practical Land Management Strategies

TSBF-CIAT is consistently asked about its policy on promotion and use of mineral fertilizers. From our perspective, mineral fertilizers are absolutely necessary but not sufficient for the productive and sustainable management of tropical soils. Long-term trials show that nutrient-use efficiency declines over time where mineral fertilizers are applied without organic inputs. An optimal soil management strategy within a given farming system depends on combining appropriate types of fertilizer with appropriate means of managing organic resources, as well as on reducing the costs of both information and fertilizer. TSBF-CIAT has already made numerous contributions to advancing such a strategy, but will continue to research this topic with emphasis on translating existing scientific knowledge into practical land-management strategies.

Our contribution is intended to quantify the use efficiency of mineral fertilizer and to design and evaluate the effects of different management options and technologies on improved nutrient-use efficiency and recycling. Special emphasis will be put on within-farm variability. We hypothesize that, given the appropriate biophysical and socio-cultural and economic context, within-farm soil fertility gradients will be economically large enough to allow a farmer to take these into account when planning the allocation of the available organic and mineral nutrient sources. We expect to deliver a framework that allows farmers to fine-tune the management of their organic and mineral resources following within-farm soil fertility gradients.

Resilient Germplasm as an Entry Point for ISFM Technology Adoption

Improved crop, forage and fallow germplasm will be used to overcome abiotic and biotic constraints and to create resilient cropping systems. TSBF-CIAT and its partners will continue to evaluate and integrate improved, adapted, resilient and marketable germplasm to tackle soil fertility constraints to crop production with particular emphasis on maize, dual-purpose legumes, and banana-based systems.

Breeding and biotechnology can help small farmers to sustainably increase productivity by:

• Considering abiotic constraints such as acidity, low P, N and drought.
  
• Selecting crop species, accessions and varieties through on-farm evaluation over a range of soils to identify potential soil-related constraints to production; and
  
• Reducing production risks, via improved drought tolerance, soil acidity tolerance, pest and disease resistance and increased efficiency of N2-fixation.
  

TSBF-CIAT and its NARES partners intend to focus on the interaction between new crop germplasm and more efficient natural resource management (NRM) in intensifying food and forage crop systems. Such a combination would consist of the best variety for a given environment grown in an improved soil using appropriate crop management technologies. Interactions between adapted germplasm and key inputs such as organic residues, mineral fertilizers and water can lead to improved use efficiency of the nutrients and water at a system level. Assessing the combination of the nutrient inputs in organic or mineral form or both in terms of resource quality, nutrient input, C, N and P dynamics and water use efficiency help to identify technology options for increasing farm productivity and system resilience. TSBF-CIAT will work with germplasm development and integrated pest and disease management specialists to evaluate the impact of improved germplasm and ISFM practices on system resilience by monitoring yield stability, profitability, soil quality (physical, chemical and biological) and ecosystem services.

Improved germplasm of crops and forages and improved livestock breeds represent a useful entry point through which to introduce better soil management practices.

Both the technology and the desired outcomes would be appropriate to the farmers to whom they must be effectively delivered. This paradigm is indeed a bridge between a commodity focus and an ecoregional approach. In addition, steps will be taken to multiply seed of these promising lines for large-scale NGO-led farmer trials. A vital aspect of these strategies is the incorporation of farmers' indigenous knowledge at an early stage of systems' development to enhance the adoption of ensuing technologies.