Raising crop response: bidirectional learning to catalyze sustainable intensification at multiple scales
Summary: The project is fully engaged with Africa RISING, CIAT and AGRA efforts in Tanzania and ready to address five "unknowns" that impede broad scaling-up of Sustainable Intensification (SI).
- It is currently unclear what constitutes 'best practices' for organic-matter technologies (OMT) such as push-pull, pigeonpea rotations, doubled up legumes and manure over the range of microenvironments, within which smallholder farmers operate. Our work will overcome these knowledge gaps.
- The project will measure on-farm nitrogen fixation of OMTs and test threshold levels of soil-organic carbon (SOC) and other aspects of soil quality, below which crops respond poorly to inorganic fertilizer. OMTs have been shown to improve nitrogen fixation, phosphorus availability, SOC and related processes, however performance on-farm is rarely documented and the number of years required to rehabilitate highly degraded soils enabling crops to respond favorably to fertilizer is not understood, nor are the range of factors that influence this.
- Knowledge is needed concerning effectiveness of novel approaches to outreach. Bidirectional learning supports an iterative process by which information providers (agrodealers, extension services and NGOs) and farmers fine-tune recommendations on OMTs, seeds and fertilizers. The team will test if this bidirectional learning, linked to mini-packs of inputs, is an effective means to support limited-resource farmers, and particularly women, to adapt and adopt these technologies.
- It will be estimated what little is known about the effects of OMT/SI take-up on nutritional outcomes of women and children.
- The project will quantify system-wide barriers to OMT/SI and engage with the Tanzanian government to guide the design of policies and programs for supporting and scaling-up SI in maize- and bean-based systems of Tanzania.
Data sets completed from a two-year, 620 household survey conducted with CIMMYT (TAMASA) across maize-based farming systems of the Northern and Southern Highlands in Tanzania, where precipitation (remote sensing down-scaled modeled weather data), soils, grain yield, household and farm practices have been linked, at multiple levels (farm and field plot). Preliminary findings are consistent with rainfall and soil carbon as important determinants of maize response to fertilizer.
Soil properties were analyzed through lab and spectral analysis, including soil texture, soil carbon, active carbon, and cations. Further, a subset of 54 households were chosen to represent a range of soil management practices and farmer SI strategies, a detailed characterization undertaken with the LandPKS app, soil analyses and a supplemental survey. Initial data has been analyzed and a manuscript is under revision, close to ready for submission.
Soil properties from three recently initiated long-term experiments near Sokoine University of Agriculture (SUA), in collaboration with N2Africa, are being analyzed for a suite of soil C and N pools.
210 VBAAs (FIPS farmer-based extension advisors) endline survey was just completed Feb, 2019. This was a highly successful means of testing of yield-enhancing technologies was carried out using mother and baby trial approaches, including seed treatment and modern varieties of beans. The three-way combination of seed treatment + modern variety + fertilizer was most reliable at enhancing yield.
- An initial and comprehensive SI assessment framework was carried out. Based on a country-wide survey data a range of intensification and SI practices by location, we have completed comparisons in five domains of performance, and considered (where data was sufficient) gender of the farmer. The SI assessment was reported at the annual SIIL meeting in Senegal.