Conservation Agriculture Research Updates - April 2026

This review article looks at the importance of plant residues with no-till and rotation (CA management). The paper mentions that rotations have spread throughout the World, but only one or two of the three principles of CA are. used in practice with no-till and crop residue more efficient at using rainfall and a more resilient agricultural system compared to conventional tillage but also no-tillage without residues. Without residues, yields are reduced. The authors show that "In areas with low rainfall, the yields were highest obtained in farms that combined NT treatments and the use of crop residues, whereas in rainfed areas with conventional (CT) systems, when residues were removed from NT systems, wheat and maize yields were drastically reduced." Also in many small-scale farms, the residue yield is low and has many competing uses. Crop residues are generally burned in the fields or fed to livestock. They conclude that NT+ R is needed for CA to be successful and adding rotation can provide even better results. 

This review from Zimbabwe reviews the Pfumvudza/Intwasa initiative that has been promoting conservation agriculture (CA) practices among smallholder farmers in this country. In terms of policy this project provides guidelines for implementation, resource allocation, and support systems. The review examines the role of government policies and institutional frameworks in sustaining CA practices in Zimbabwe using a literature review analyzing peer-reviewed articles, policy documents, and government reports published between 2000 and 2024. Results both strengths and limitations. The authors mention that policies promote conservation agriculture, inclusive participation, and resource distribution, but challenges such as inadequate institutional coordination, limited extension services, and funding constraints limit the success of this program. The report recommends "policy harmonization, targeted investments in extension services, and the promotion of equitable resource distribution. Additionally, leveraging technology for monitoring, enhancing market access for smallholders, and fostering public-private partnerships will support the scalability and sustainability of this project"

This paper from Rwanda looks at the low yields of maize, a critical staple crop in this country. The study evaluates the agronomic and economic results of CA compared to conventional systems (CT) by interviewing 222 farms in dry areas of Eastern Rwanda. They found that CA farmers incurred higher total production costs, particularly for fertilizers, seeds, weeding, and irrigation, while CT farmers had significantly higher land preparation costs. But CA achieved 40% higher net profit, 20% higher maize yields, and higher P use efficiency compared to CT. They identified irrigation frequency, seed rate, and nitrogen and phosphorus fertilizer application as key determinants of maize yield using CA compared to CT. 

This paper from Bihar, Eastern India, looks at raised bed planting (RBP) for smallholder maize farmers. They evaluated this management system for 4 rabi (winter) seasons and compared with conventional flat planting (FP). They looked at yield, profitability, water use efficiency (WUE), and nutrient use efficiency (NUE). Maize yields were much higher under RBP than FP but also more profitable with higher net returns, better WUE and NUE. Farmers need to be motivated to adopt this system for Rabi maize. 

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.

The authors of this paper are looking at traditional grains like sorghum, pearl and finger millet to combat climate change and drought in sub-Saharan Africa (SSA) as alternatives to maize the staple food in this area. The main objective of this review paper is to identify suitable equipment for smallholders to mechanize growing these traditional grains. They reviewed six databases to find suitable equipment used globally. They found that the mechanisation of traditional grain production operations is lagging behind that of other cereals and so there is a need to work on development of suitable equipment  for smallholder farmers. They suggest use of two-wheel tractors and service providers as a way to move forward. Policy decisions and recommendations for improvement were made.

Despite CA being promoted and a possible solution for food insecurity resulting from climate shocks and soil degradation, adoption in Malawi is still low. This paper looked at social capital as a way of approving adoption. The interviewed 1512 smallholder farmers to find out how different social capital elements influenced farmer decisions to adopt CA. Factors that positively affected adoption were group membership, relations with leadership, land size, extension services, livestock ownership, and available credit. Full adoption of CA was limited compared to partial adoption. They conclude that better policy is needed to promote farmer organizations, community engagement, and training programs to enhance adoption.

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 from Malawi, looks at the effects of using the legumes pigeonpea (PP) and cowpea (CP) as intercrops with maize (M) in a deep bed farming (DBF) system compared to conventional tillage (CT) over two years on a farmers field. There were 7 main plots that included just M, CP and PP; M intercropped with CP and PP; CP intercropped with PP; and M plus N topdress. The subplots were DBF and CT. DBF is a form of CA that starts by doing deep tillage with a pick axe or hoe to break the plow pan so roots are deeper, better aeration, infiltration of water. Then CA management is done. The beds can be made along a contour. Results showed DBF and CT with legumes had higher yields than without. DBF was better than CT. Intercropping had higher land productivity than sole cropping indicating the introduction of a legume improves yields.

This study explores the experiences and perspectives of smallholder farmers from 6 locations in the Eastern Gangetic Plains where promotional activities since 2013 were part of a "Sustainable and Resilient farming system intensification". There were 3 locations in India, two in Bangladesh and one in Nepal. After coding of data from semi-structured interviews with 44 experimenting farmers and 38 interested non-users, ten common themes emerged that explain why farmers stagnate in their adoption process for CA. Seven of the ten themes were non-specific to CASI and would constraint promotion and uptake of any agri-system change. 4 factors are used in this study to address agricultural change for smallholder farmers; targeting, training, targeted incentives, and time. They conclude that there is a need for a stronger focus on enabling environments rather than technological performance evaluations generically, if promotional efforts are to be successful and emerging sustainable intensification technologies are to be adopted by smallholder farmers.

This paper explores the performance of cropping systems with different legume diversity on maize productivity in Zambia and determine the minimum land required to reach maize self sufficiency at the household level using the different systems. Six maize-based cropping systems, comprising maize monocropping, maize-legume rotations and intercrops under ‘conventional’ tillage and conservation agriculture, were evaluated across 40 farms in Zambia. The results are provided in this paper. They conclude that introducing legumes into their maize systems can increase yields of maize and intercropping legumes can be used in land restricted farms.

This paper looks at diversification of maize-based systems with legumes  to counteract climate change and soil fertility decline in Zambia. Maize-legume diversification strategies included single row intercropping, strip cropping and crop rotation under CT and CA in 4 Districts in Zambia. Data was collected from on-farm trials over 3 growing seasons. Results showed no significant effect of cropping systems on individual maize and legume grain yield across growing seasons, but substantial nutritional and economic benefits of intercropping systems due to simultaneously growing two crops especially in maize-legume intercropping strategies compared to sole maize and maize-legume rotation. Although there was increased labour requirements to manage the intercrops, these cropping systems had much higher net benefits and returns to labour and inputs than the other cropping systems tested.

This review looks at the challenges of meeting food demands in South Asia complicated by climate change. They contend that CA can help resolve challenges of soil health, climate change, water scarcity, pollution, profitability and human health. This review uses published literature to look at how CA affects SOC and therefore soil health, carbon sequestration and GHG emissions. The results from several studies show CA increased SOC and improved soil health mainly in the surface layer. CA also made a positive impact on nutrient availability. The present gaps in knowledge of soil health assessment and research to fill the gaps are also included in this chapter.

Manual methods of farming are common in Africa and also in Zimbabwe where this paper was written. It measures the fuel consumption needed to use a two-wheel tractor to relieve the drudgery of manual farming in this country. This is important for calculating the cost of mechanizing agriculture and GHG emissions. This study measured fuel consumption for 2-wheel tractors in direct seeding for sorghum and pearl millet crops in sandy soils at varying speeds of operation. The information in this paper can be used by farmers and other operators of 2WTs for planning the fuel quantity and budgetary requirements.

This paper looks at smallholder farmers issues with tractor mechanization using a survey of 208 farmers, 18 focus groups and 28 key informants in 3 Districts of Zambia. Issues looked included adoption, preferences for ownership, and financing. Tractor ownership revolves around improvement in productivity but also income generation from service provision to other farmers tied to better timing and narrowing planting windows. Differences in gender affect ownership with males preferring individual ownership and females prefer group ownership. Incentives for ownership were best for risk-contingent credit especially if bundled with repair insurance. Barriers to adoption included high maintenance costs' poor access to spare parts and financial issues. They conclude that "successful interventions must be flexible, gender-responsive and tailored to the local context." 

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 review article explores the role of farmer agency in enhancing the effect of extension models related to soil health. They want to empower farmers to innovate and adapt knowledge to identify more efficient systems. It reviews several factors that can improve farmer agency including education, economic opportunities, social networks and supportive policies. The paper proposes the need for policies and programs to improve farmer decision-making opportunities and farmer centered learning platforms, digital tools and to strengthen social networks with the hope that adoption and adaptation soil health solutions improves.

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 study looks at the impacts of no-till individually and with other CA practices on nitrous oxide (N20) emissions and yields using a review of 1270 observations from 86 peer-reviewed articles. Results sho that yields increased by 9.1% while reducing N20 emissions by 6.8% compared to conventional tillage (CT). The results also showed that reduction of N20 emissions and yields were even greater when using other CA practices like residue retention and rotations; reductions in N20 of 15% and increase in yields of more than 30%. The mitigation of N20 emissions was higher in dry versus humid climates. They conclude that "Smallholder farms in Central Asia, South Asia, and sub-Saharan Africa appear particularly suitable for the adoption of conservation agriculture, whereas, in humid climates, high nitrogen (N) input management and silt-clay loam soil should be applied with caution. 

This article from Ghana looks at the effect of CA adoption by smallholder maize farmers of their food security. 400 farmers were selected that had been introduced to CA. The findings of the study show that crop rotation, row planting, fertilizer application, improved seeds and cover cropping were the CA practices often implemented by the farmers. The main issue highlighted by these farmers was poor access to credit for applying CA but CA did improve their food security.

This study from Tanzania looks at farmer strategies for adaptation to climate change. They surveyed 330 smallholder farmers. It was found that farmers have a number of strategies but the following 4 were key ones: drought resistant varieties, early maturing ones, resistant livestock breeds and conservation agriculture, with farmers choosing more then just one. The paper also categorizes the samples into 4 groups taht you can find in the paper. The conclude that these factors need to be considered in any policy decisions to ensure better adoption and adaptation strategies.

Conventional farming in Sub-Saharan Africa (SSA)  is resulting in soil degradation. This paper reviews current practices, challenges, and constraints to the adoption of CA in SSA to reverse this degradation. They show that CA is only adopted on 1.25% of cultivated land in SSA despite 2 decades of promotion. The paper lists 6 possible reasons for this lack of adoption of CA. They also suggest that adoption by smallholder farmers is also obstructed by socio-economic factors due to smallholder farmers’ focus on short term yield increases and their lack of access to markets, loans, and education. They conclude that wider adoption by smallholder farmers in SSA requires CA approaches that are downscaled to fit the existing tillage tools and the specific agroecological and socio-economic farm settings.

This paper looks at farmer strategies for future climate variability and climate change in Tanzania. They used a cross-sectional research design in a survey of a random sample of 330 small-scale farmers. The results show that farmers use a number of strategies, but 4 key adaptation strategies - drought resistant varieties, earlier maturing varieties, resistant livestock breeds and conservation agriculture (CA) - emerged. Farmers also used more then one strategy with choice determined by multiple factors. The paper categorizes the factor into 4 groups that in summary include individual farmer/household; farm characteristics; institutional factors and; local knowledge. They suggest these factors should be available for policy development.

Sentinel sites that had promoted CA for a long time were used in this paper. The paper attempted to understand what led to the success of CA adoption. They surveyed 620 farmers in Malawi divided into two groups ; those who had contact with host farmers and a control group. Almost a third of the farmers in both groups adopted full CA over a 2-year period, but 57% of the farmers in the treatment area adopted full CA but on 7% in the control group. However, fewer farmers adopted CA for a longer period even in the treatment areas with some dis-adoption. The key adoption factors in the sentinel sites include the availability of training, dedicated longer-term extension support coupled with farmer experiential learning through demonstration plots managed by host farmers. This peer to peer learning over time is critical for sustained adoption.

There has been a rise in the number of market-oriented farmers, known as `emergent farmers,' who acquire and utilize tractors and associated implements for agricultural production to Zambian agriculture. This study examined the behavioral intentions of Zambian emergent farmers concerning Mechanized Conservation Agriculture (MCA) using the Decomposed Theory of Planned Behavior constructs: attitudes, perceived behavior control, subjective norms, and farmers' background factors by surveying 119 emergent farmers. Factors such as media influence, social influence, technical training, and extension services had positive but insignificant effects on farmers' intention to adopt MCA. Background factors, including overall farm size, farmer's age, area under CA, and years of CA use, showed a positive and significant correlation with farmers' intention to adopt MCA.