Conservation Agriculture Research Updates - April 2026

This paper starts out by saying that in Sub Saharan Africa (SSA) tillage and burning of residues is mostly used that causes soil erosion. Maize is also the major crop in smallholder diets. They used the APSIM model to simulate the productivity and protein yield of a variety of intercropping systems involving three crops (maize, cowpea and pigeonpea) under full CA practice relative to conventional tillage (CV) with the same intercropping system. The baseline scenario used daily climate data from 1997-2015 in Northern Mozambique. The results are given in the paper but the Authors conclude that "although under the CA system, there were ng declines in grain yields nevertheless, protein yields and overall productivity remained consistently higher under the CA system.

This paper looks at the impact of CA in an Ethiopian district on crop productivity using cross-sectional household data from 322 subjects in two agro-ecological zones. There were 168 CA and 154 non-CA farmers. The project's findings highlighted the need for policies that support and enable a more frequent and successfully established communication link between farmers with agricultural experts at the regional, zonal, and district levels, as well as agricultural extension personnel at the local level. There is a need to adopt crop and soil management systems on farmland,that results in improved soil quality consistently for improved crop productivity.

This paper looked at the combined influence of tillage and crop management (conventional (CT) and no-tillage (NT) with living mulch (LM)) and weeding regimes on nematodes, free living and parasitic in the Madagascar highlands 7 years after the establishment of the experiment. Results showed that the population of free living nematodes was almost 4 times more in NT+LM than CT. But plant parasitic nematodes were the same in abundance for both tillage treatments but differed in taxonomic  composition. They concluded that CA and no-weeding proved beneficial for promoting free-living nematode communities but also to decrease the overall plant parasitic pressure through plant diversification. As no weeding may nonetheless affect crop yield, a trade-off has therefore to be found to promote soil ecosystem services while maintaining crop production.

This paper from Malawi looks at ways to overcome the problem of climate change impacts that have affected food production. They looked at improved varieties on total productivity and nutrition under maize-legume CA systems over 13 years of on-farm experiments in Malawi. the 3 main treatments were 1. CT of sole maize planted on raised beds; 2. NT of sole maize on retained ridges + residue; and 3. CA maize intercropped with either cowpea, pigeon pea or groundnut on retained beds using NT. The results showed that total system nutrition was highest on the 3rd main treatment. The yields of maize were significantly higher in the 2nd and 3rd treatments irrespective of the variety grown. They conclude that "Conservation agriculture and NT systems have more influence on productivity of smallholder farms, despite the genotypes used (hybrids or OPVs)."

This paper from the World Agroforestry Center in Kenya, looks at the combination of CA with trees as a way to increase profits, yields and lower production costs. This study was started in 2012. There were two systems; conventional agriculture (CT) and CA. There were 10 subplots with 3 shrub species; Calliandra, Pigeon pea and Gliricidia, each planted at 3 spacings to allow maize-legume intercrops. Data included costs of production, local market costs for the maize and legume crops, and calculation of benefit-cost ratios (BCR).  Results showed significantly higher BCR under conservation agriculture in all seasons. They conclude that conservation agriculture both with and without trees is beneficial for the farmer, with higher net benefits compared to conventional tillage

This paper examines farmer adoption decisions for CA in two semi-arid areas of SW Ethiopia. They surveyed 392 households in two District farming systems. Two groups of farmers that practice that practice CA and CT were selected. A binary logistic regression model was used to answer the question of factors that determine smallholders' initial decision to adopt CA. Nine explanatory variables were included in the analysis. The results show that CT groups have higher schooling, farmland holding, and livestock relative to CA-practicing households. Farmers decision to adopt CA was high when extension services were available and they lacked of access to small-scale irrigation. The impact of extension service has indispensable benefits in extending the knowledge to younger smallholders.

This is another article looking at CA combined with agroforestry (CAWT) in smallholder farming in Kenya. CAWT is an agroforestry system that integrates legume trees and shrubs into cropping fields under minimum soil disturbance and tillage. The paper looks at key soil quality indicators (SQI) under CAWT. The research assesses the effects of CAWT components; tillage (CT or NT), leguminous trees/shrubs (Calliandra calothyrsus, Gliricidia sepium and Cajanus cajan), and their inter-row spacing (1.5 m, 3.0 m or 4.5 m) on SQI in the dry-land agroecosystems of eastern Kenya. They conclude that a shift towards CAWT showed evidence of improving soil quality, nutrient availability and increasing soil nutrient thresholds that can potentially support maize production.

This paper evaluated CA as practiced by farmers and compared farmer understanding of soil health in three East African countries. CA and non-CA fields were compared by sampling for 2-3 years. CA and non-CA fields were located close, on soils with the same texture, growing similar crops. Most of the CA fields were planted in basins. Farmers and technicians collected the data together. Farmers said that CA improved hoe-ability, crusting, smell and water infiltration. Fields under the CA treatment had a higher probability of rating better than non-CA fields. The paper discusses both benefits and drawbacks of using participatory, on-farm research. They conclude that farmer participation as citizen scientists will advance soil restoration in East Africa and increase the potential for farmer-to-farmer knowledge exchange of soil-improving practices.

This paper reports on the use of "Push Pull Technology" (PPT) in maize that they use to control insect pests (stemborer) and parasitic weeds (Striga) in low fertility soils using two farming practices -- CT and CA - in Malawi. Stemborer and Striga infestations were investigated and the suitability levels of two Desmodium species as cover crops. Farmers' perceptions of PPT were gathered through a focus group discussion. The performance of PPT varied significantly between treatments, sites, and years on grain yields and the number of cobs that could be assigned to soil attributes. Results reaffirmed the technology's agronomic benefits in productivity, pest management, plant vigour, and Striga control. The cost of labour was described as a challenge, and research to identify more suitable Desmodium species is needed. They emphasized the importance of Desmodium and Brachiaria as animal fodder to improve the adoption of the technology.

This long term study evaluated and reports on CA, but with bed and furrow planting on soil health using teff, wheat, barley and grass-pea in Ethiopia. They used permanent raised beds (PRB) and contour furrowing (CF) and  conventional tillage (CT). Soil from 0-10 cm depth was used for evaluating soil health and crop yield. Arbuscular mycorrhizal fungi spore abundance and root colonization was higher in PRB followed by CF compared to CT. Higher straw and grain yield were recorded for PRB, CF and CT, respectively. A PSEM model highlighted two pathways in which CA-based systems contributed to improved productivity: (a) via higher density of bacteria and improved hydraulic conductivity, and (b) via higher density of fungi and increase soil organic carbon content in the topsoil. They conclude that CA can improve yield through improving soil health.

This paper presents overview findings from trans-disciplinary research projects from Southern, East, and West Africa to evaluate the potential importance of integrated participatory soil health studies designed to inform context-specific recommendations and policies for resilient African food systems. The paper identifies how integrated research can help shared learning and knowledge exchange required for upscaling sustainable land management practices enabled through enhanced farmer participation.

This paper looks at two tillage treatments, NT and CT, on 4 crop covers; monocrop maize, monocrop soybean, rotated maize, and intercrop of maize and soybean on infiltration of water. Tillage and crop cover both affected infiltration with NT infiltration better than CT. The authors conclude that NT with greater cover improves infiltration and soil water storage.

This paper looks at the determining factors that influence the adoption of reduced tillage by smallholder farmers in Kenya. The data comes from 300 random selected households of maize dominated farming systems. 437 plot level analysis using Probit regression estimates the decision model.Access to extension information is the key determinant. Household labor availability, land allocated for maize crop, and plot-level characteristics such as soil type, plot size, and intercropping practice followed on the plot are also found to have influenced adoption.

This research from Uganda looks at nitrogen fixation with pigeon peas in a maize dominant cropping pattern to investigate the effect of biochar under CA on nitrogen fixation at three sites located in different agro-ecological zones. CA involved minimum tillage with planting basins established by hand hoeing. There were 4 treatments: (1) conventional tillage with crop rotation (CT), (2) minimum tillage with crop rotation (CA), (3) CA and plus biochar, applied in both first and second year (CA+BC+BC), and (4) CA and biochar, applied once in the first year (CA+BC). Grain yield was significantly increased by biochar application in CA systems compared to conventional practices, in all seasons and sites. They conclude that "Biological N2-fixation was positively influenced by biochar application under CA systems". 

This paper from Uganda looks at the adoption of sustainable agricultural intensification practices (SAIPs) recommended for smallholder farmers.320 maize farmers were interviewed in 2 Districts. Results showed that improved maize varieties, conservation tillage, legume intercrop, integrated soil fertility management (ISFM), and integrated pest management (IPM) were adopted by 58, 36, 44, 52, and 56% of the farmers. Institutional factors were significant predictors of adoption. Socioeconomic factors only positively influenced adoption intensity for SAIPs. Two policy recommendations were to strengthen agricultural extension and promote the use of village level credit services to enhance adoption.

This study examined types of adaptation strategies implemented by males/male-headed households and females/female-headed households and how these influence food security.They used a household food insecurity Access Prevalence (HFIAP) and a probit model to assess food security and adaptation strategies. They collected data from 521 household in Kenya and 1,049 adults. Many of these respondents mentioned reduced and less predictable rainfall resulting in longer droughts that affected productivity. The respondents used three adaptation strategies to  address the above problems: CA (69%), changes in planting dates (49%) and planting drought tolerant crops and varieties (47%). More male dominated households that female used all 3 strategies. Access to credit, non-farm income, types of crops grown, and weather perception variables were the important determinants of adaptation. They conclude that the three strategies worked to increase food security for male dominated households but not female dominated households who are more susceptible to climate change and suggest policies are needed to help female headed families.

This paper reviews the history of agricultural extension in Zimbabwe and presents recent research findings on Ag Extension Officers (AEO) training and gaps in the curriculum. The data suggests that a gap in skills exists because of insufficient AEO training in essential areas including farm management, market access, emerging technologies and being able to support the changing needs of farmers. The authors suggest that the greatest need is for agricultural extension services for new farmers and emerging agricultural technologies compared to well-established farmers and farming methods.

This paper looks at sustainable intensification systems that can help address hunger and malnutrition. It looks at dietary diversity in maize-based farming systems in Zambia and Zimbabwe. They surveyed 1124 households and explore pathways from intensification to dietary diversity. They found significant positive associations between the adoption of sustainable intensification practices (SIPs), such as minimum tillage, minimum tillage and crop rotation, and minimum tillage and intercrops and improved production and crop diversity and in turn, dietary diversity. But they conclude that these benefits depend on adoption of SIPS so there is a need to overcome the bottlenecks to adoption.

This study identified various Climate Smart agricultural (CSA) practices widely adopted in the Ethiopian study area for impacts on rural farm households food security and poverty. 278 households were randomly selected from two kebeles from each district and data collected using a structured and pretested survey questionnaire. Widely adopted CSA practices were conservation agriculture, soil fertility management, crop diversification, and small-scale irrigation. The results illustrated that adopter households on average showed a higher food consumption score, dietary diversity score, and less food insecurity experience than non-adopters. They conclude that more is needed to up-scale CSA practices.

This study looks at maize and beans intercropped under no-till with residue retention on composition  and population of soil fungal species in Kenya. Soils were collected from 64 farmers where half had used CA and the other half conventional tillage (CT) for 5 years. In CT land was dug by hand held hoe and residue removed. CA resulted in increased soil fungal populations as compared to CT. There was no significant difference between CA and CT on crop diseases. 

This report looks at the evaluation of a 5-year Canadian Foodgrains Bank implemented project in Sub-Saharan Africa entitled "Scaling-Up Conservation Agriculture in East Africa (SUCA). The three outcome areas of this project were the adoption of CA, an enabling institutional environment and promotion of enabling policies. This case study illustrated the overlap between utilization-focused evaluation ((UFE) and collaborative  approaches to evaluation (CAE). This program supported 50,000 male and female farmers practicing 2-3 CA principles using 11 implementing partners. The findings demonstrated the value of the program and inspired a framework called CA Plus that illustrates the multidisciplinary approach underlying the program's success.

This paper from a sub-humid area of Uganda looks at ways to conserve water and increase water use efficiency (WUE) in rainfed areas to overcome issues of unreliable rainfall and high evapotranspiration during critical growth stages. They evaluated different climate smart agriculture (CSA) practices, such as mulching and permanent planting basins (PPB), on maize growth, yield, water use efficiency and soil moisture storage. They showed that maize biomass significantly increased under the tested CSA practices in the study area. Permanent planting basins increased maize grain yield (11-66%) and water use efficiency (33-94%) compared to the conventional practice. Mulching also increased yield and WUE relative to the control and significantly increased soil moisture storage compared to PPB and the the control without mulch.

This is an interesting study on the utility of various two-wheel tractor seeders for wheat and maize in Ethiopia. Seeders tested came from Brazil, Bangladesh, China, India, and USA. Field operating capacity, fuel consumption, and crop yield were evaluated over two years in two locations. Fuel consumption was between 9.4 L ha-1 and 12.6 L ha-1 depending on seeding depth. A ten-fold reduction in operating time was possible relative to the non-mechanized conventional practice. Improved uniformity and timing of planting resulted in yield increments of 29% and 22% for wheat and maize, respectively. The Bangladeshi and Chinese equipment was best for wheat. For maize, the John Morrison and VMP seeders outperformed all other units. The paper recommends the possibility of manufacture of this equipment locally to reduce costs and increase adoption.

This paper aims to provide evidence that payments for ecosystem services encourage the adoption of conservation practices like CA. By providing financial incentives, this paper demonstrates that it is possible to  increase the extent and intensity of CA adoption. Also mechanisms that leverage social networks for the consolidation of fragmented land may be more effective at bringing more land under conservation objectives. They also demonstrate that some of the supposed weaknesses hindering the adoption of CA – lower yields in the short-run and higher expenditures on weed control – were not necessarily obstacles in their study area. They suggest that the provision of subsidies need not continue into perpetuity, but may only be needed to overcome short-term transition costs.

This review looks at whether CA is a Climate Smart practice and why adoption by smallholder farmers in Eastern and Southern Africa is low. They use an adoption framework to achieve this and look at the different components of CA. Their results suggest CA can contribute to productivity and resilience but varies by farm, household and region. They show that capital-intensive (mechanized) CA is more likely to be adopted in areas of economic dynamism where capital is cheap relative to labor. Labor-intensive CA practices are more likely to be adopted in regions of economic stagnation where capital is expensive, and labor is abundant and cheap. They conclude that CA is climate smart and if adopted widely, has the potential to help build resilience in smallholder farming systems.