Conservation Agriculture Research Updates - March 2026

This paper from Brazil looks at the role of cover crops to improve soil fertility, plant nutrition and soybean yield in the Cerrado area in a dryland area. There were 8 cover crops, and fallow preceding soybeans grown in the off-season. This area had cultivated soybeans under no-till for 10 years. They measured the biomass of the cover crops, but also soil chemical and biological properties, soybean foliar nutrients, yield and quality. Data can be found in the paper and abstract. They concluded that "Cover crops improved soil fertility while increasing soybean productivity, thus being an effective strategy for the achievement of sustainable soybean production."

This review assesses the effect of CA management on soil biological, chemical and physical properties. Results show that CA improves soil structure, enhances soil organic carbon sequestration, promotes microbial activity, increases water-use efficiency, and reduces erosion and nutrient losses. The paper also reports on environmental, economic, and social benefits of CA that include biodiversity conservation, reduced greenhouse gas emissions, improved yields, and increased food system resilience. They also look at the the socioeconomic conditions, institutional frameworks, and policy interventions that shape CA adoption and impact and the CA research gaps and future of CA directions.

This review from Romania highlights the importance of soil health for sustainable agriculture and identifies practices that result in improved soil health that includes, physical, chemical and biological properties. The explored rotation, cover crops, no-till, CA, and use of organic amendments to achieve SH properties that includes better soil structure, increased organic matter and biological diversity. Increasing soil organic carbon (SOC) is vital. Their results show that CA is a better option to restore soil health than conventional systems although they mention that this topic is still controversial among scientists and farmers. 

This long-term field experiment with Winter wheat looked at 3 tillage systems: conventional (CT), reduced (RT), and No-till (NT) since 1995. They collected data on SOC, microbial biomass, and enzymatic activity in four-year crop rotation periods from 2005-2024. There were 3 rotations: winter oil seed rape, winter wheat, pea, and winter wheat.Data was collected from 3 crop depths: 0-10, 10-20, and 20-30 cm. Residues were incorporated in CT, partially in RT and left as surface mulch in NT. Results showed that NT had the highest C-sequestration followed by RT and CT. The weather conditions during the year (abundance of precipitation) influenced crop yields significantly more than the tillage practices with wheat yields and N in grain the highest in CT followed by RT and lowest in NT. NT treatments increased the organic carbon and microbial activity in soils.

This study looked at the components of CA individually and in combinations with a control on soil carbon and nitrogen dynamics for a direct rice seeded-green gram system. Reduced tillage alone and in combination with rotation resulted in 10% and 6% lower CO2-C release than the plots with residue retained. The paper has results on the role of rotation and crop residue on various enzymes. They conclude that rotation and residue retention are effective for better C and N cycling in this system. Tillage on the other hand needs a longer time to show beneficial results than the 4 years of this study. The increase in soil enzyme activities improved microbial activity, which can further enhance nutrient availability for plants. and help improve soil health.

This paper utilized bibliometric analyses to map the conceptual and intellectual structure of soil health research from 1996-2021. They reviewed 984 peer reviewed papers that they divided into 3 major research clusters. The analysis revealed critical gaps, including limited integration of pedological modeling to quantify ecosystem services and insufficient long-term studies on conservation agriculture. They recommend that interdisciplinary collaboration among agronomists, microbiologists, policymakers, and climate scientists to align soil health metrics with global targets providing a roadmap to integrate soil health into climate-smart land-use policies.

This study was done in the US upper Midwest over 3 years. There were 15 field pairs with one using conventional (CM) and the other soil health management (SH) (reduced tillage, cover crops and crop diversity). They assessed these plots by looking at soil organic matter pools, microbial indicators and a physical indicator. Wet aggregate stability improved in the SH plots compared to the CM ones. Results showed that most soil properties were significantly responsive to two management combinations, 1) tillage x cover crops, and 2) tillage x cover crops x crop diversity. Microbial indicators along with potentially mineralizable nitrogen (PMN) exhibited the strongest increases in the SH plots.

This paper studies the effects of no-till (NT) and residue over the long- and short-term (24 and 3 years) in a semi-arid area of Mexico in a maize-oat-triticale system established in 1995. There were 6 treatments: plow+harrow (PH), harrow (H), multi-plow (MP), No-till (NT), NT with 33% residue, and NT with 66% residue. Soil quality was increased with NT + R by increasing SOM but also total carbon and enhanced microbial abundance. Tillage treatments, however led to lower SOM and lower yields. Differences were also visible soon after the experiment was initiated.

This paper looked at longterm soil ecosystem status of farmers adopting CA under two different management and environmental conditions in Southern Africa using conventional systems and grazed grasslands as checks. Various soil chemical, physical and biological properties were measured. At one of the sites pasture and conservation agriculture systems presented elevated organic matter content and microbial activity due to continuous organic cover and minimal physical disturbance and essentially healthier soils. In the second site differences between conservation agriculture systems were strongly associated with soil texture differences, influencing organic matter and respiration rates. This means that tailored systems to complement on-farm options and local conditions are needed.

This paper from Mexico looked at the the impact of conservation tillage (CT) versus intensive tillage (IT) on bacterial communities from experimental platforms that had practiced these three different tillage options for 25 years. The three tillage options were IT, CT and reduced tillage (RT) with residue with and without for each tillage practice. CT or conservation tillage showed higher species diversity and beta diversity while IT showed higher richness. IT results were grouped in the same phylum range whereas CT had a different range. CT also improved the soil physicochemical properties. Although not mentioned in the abstract, zero tillage and reduced tillage systems  led to the development of copiotrophic ecological niches, predominantly attributed to heightened organic matter levels stemming from the decomposition of agricultural residues and wastewater irrigation.

This narrative review synthesizes the insights of the soil health practices adoption literature, with a focus on common farming practices that can improve soil health and enhance crop yields, reviewing the results of various approaches and pointing out the challenges and opportunities for implementing sustainable agriculture on a larger scale.Results show that Conservation no-till is better for soil health than conventional tillage. However, agricultural yields increase more with intercropping, crop rotation, and cover crops than monocropping. The paper identifies the most suitable practices for improving soil health

This paper looks at the effects of CA versus conventional management (CM) on 17 soil properties, microbial during 8 years of climate warming in China. Results showed an increase in soil health with CA management in terms of increased SOC, and soil microbial biomass carbon and fungal diversity. This led to increased wheat yields over the 8 years but only in CA. They conclude that CA management increases soil health leading to higher yields despite the climate warming trend. CM did not show this improvement.

This 15 year long-term experiment from Haryana State in India using a rice-wheat system was designed to measure the impact of 15 years of tillage and residue management on the soil quality index (SQI) and yields. There were treatments: 1. CT without residue (-R); CT with +R incorporated; Reduced tillage (RT) with -R; RT +R incorporated; NT -R; and NT +R left on surface. Soil measurements included various physical, chemical, and biological properties. Results showed that NT+R had the lowest bulk density and soil penetration resistance at the surface soil leading to better water infiltration. Also improved SOC, and microbial activities. Wheat yields were higher for NT + R, but lower for rice yields. This was related to using direct seeded rice and probably having more weeds than in the transplanted conventional rice. 

This paper from Italy looks at using tillage radish (TR) in place of fallow to see if it improves soil health. The studied the effects of this cover crop on soil health indicators related to C, N and P cycling in two different climatic conditions using CA practices. Biomass and P uptake by the TR were higher in one site than the other that also had higher levels of SOC in the top layer of soil. TR increased SOC, labile organic C, soil P test, and microbial biomass C, N, and P, but amounts varied by location. They conclude that "TR's positive effects on some soil health indicators related to relevant ecosystem services, particularly C storage, microbial biomass, P mobilization and recycling, and N balance, with site-specific variations depending on pedoclimatic conditions."

This study examined CA practices in a maize-wheat system in India using a 2-year field study with 15 treatment combinations. Their results showed that No-tillage (NT) with residue retention (+R) and phosphorus dose (34.4 kg P ha⁻¹) produced the highest (8.17 t ha⁻¹) maize equivalent yield, system productivity, and net economic return. NT + R also significantly enhanced soil organic carbon, water-stable aggregates, microbial biomass, and enzymatic activities. In contrast, phosphorus application with microbial inoculants under NT without residue (-R) yielded the highest energy use efficiency. They conclude that "integrating CA-practices and optimal phosphorus management enhances system productivity, profitability, and soil sustainability."

This paper from Europe used a Meta-analysis to to evaluate the impact of management practices related to carbon and nutrient, vegetation, pest and disease and soil management, as well as grazing management on soil biota and soil biology. They screened 698 articles and came up with 90 that were eligible with a total of 790 pairwise combinations and 74,526 observations. Their study showed what agricultural practices improve or reduce soil biology that is useful for selection of sustainable farming systems. They found that reduced tillage, organic fertilization, cover cropping and intercropping resulted in positive improvements in soil health factors. They also developed a “Utility-Robustness” scoring system for soil actors, using a systematic framework to inform biological indicator selection tailored to specific management contexts.

This is an interesting review of how Brazilian farmers moved from a tillage intensive farming system to one that used no-till, permanent soil cover, and rotations or conservation agriculture. In Brazil over 52 years, no-tillage systems (NTS) evolved allowing Brazil to move from a major importer of agricultural products to one of the largest producers and exporters globally. This paper reviews how this came about. It was spontaneous without any specific incentive program or policy. It was also because of the farming sector in Brazil who was responsible for this mobilization and sought alternatives that led to less impacting soil management allowing a more sustainable intensification of agriculture. The farmer sector included farmer organizations and companies responsible for supply of inputs and equipment suitable for seeding in no-till soil with permanent residue soil cover. Academia and research acted in the background at the strat but have now become more active. 

This paper reports on the long-term effects of different tillage practices and crop residue management on soil biological and physical health using winter wheat and a fodder radish cover crop. The experiment started in 2003 and samples taken in 2021. There were three tillage treatments: direct sowing (NT), harrowing to 10 cm H), and moldboard plowing to 20 cm (MP). Residue was either removed or left in the plots. The biological soil measures were two fatty-acid biomarkers arbuscular mycorrhizal fungi (AMF)and glomalin-related soil protein (EE). Soil physical indices were water stable aggregates (WSA) and five soil pore characters and SOC. CA practices increased AMF biomass and harrowing and NT resulted in stratified SOC. Residue increased SOC levels. They conclude that their study identified the significant role of AMF in maintaining soil health.

This study from Brazil looked at the effect on conservation tillage in a subtropical area of China in order to evaluate its suitability for maize in such areas. There were 3 tillage treatments; no-tillage (NT), earthworm bio-tillage (EBT), and traditional rotary tillage (RT). Also 3 residue treatments; none (O), straw (S), and composted cow manure (M). Maize yield and soil samples (0–10 cm) were collected after four growing seasons to determine the maize production, soil properties and microbial communities. Both no-tillage and earthworm bio-tillage increased soil pH, organic carbon, nitrogen and phosphorus contents, especially with cow manure additions, and increased the general bacteria and gram-positive bacteria under none input. No-tillage significantly increased microbial biomass carbon, especially with none and straw inputs.

This paper from Canada looks at application rates of Glyphosate (GBH) to terminate cover crops and how this influences soil microbial communities. They used 3 GBH application rates in maize, soybean and wheat fields grown with direct seeding (NT) with and without cover crops. Results showed that DS+CC did not significantly impact microbial richness compared to DS, but did alter specific abundance among prokaryotes and eukaryotes but that the three crops significantly influenced the composition of eukaryotic communities in 2018 and 2019, but not prokaryotic communities. They conclude that the study calls for sustainable agricultural practices that preserve microbial diversity, which is essential for maintaining ecosystem services and soil health.

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 provides an overview of the science and farmers’ expectations of conservation tillage (CST) in six European countries, including Croatia, Serbia, Hungary, Slovakia, Czech Republic, and Poland where traditional intensive tillage results in soil erosion, loss of SOM, and soil degradation. This review looks at the adoption on CST in these countries and looks at the current progress and future prospects. CST provides adequate soil cover, minimizes erosion, and encourages biological activity and organic matter accumulation that results in improved soil productivity and resilience against additional degradation and climate variation. Results showed a high level of diversity in readiness and willingness to accept, as well as different levels of knowledge about the adoption of CST, but adoption is increasing and this represents a key way to slow soil degradation and adapt to climate change.

This article aims to better understand the interaction of no-till and residue management affect the soil microbiome. Soil was collected from a long term field trial that had CT and nt and plus and minus residue. Stubble management markedly altered both the taxonomic and functional composition of the prokaryotic community, the addition of stubble caused a significant increase in Proteobacteria, but a decrease in Chloroflexi compared with no stubble. Stubble retention increased the availability of carbon resources in the soil, resulting in a higher proportion of genes functional for metabolic activity and plant–pathogen interactions. However, tillage practice did not influence the structure or diversity of the soil prokaryote community.

This paper from Iran looks at the effect of 5 years of CA managment on the quality and diversity of soil macrofauna in rainfed in semi-arid areas of Iran. Treatments included conventional moldboard tillage (CT), reduced tillage with a Delta  model and roller (RT1), Chisel plow and roller (RT2) and no-tillage. There were 3 subplots with no residue, 1/3 residue and 2/3 residue. Wheat rotated with chickpea was the cropping pattern. The results showed that no-tillage led to a significant increase in macrofauna biodiversity in both wheat and chickpea soils. Also keeping 1/3 residue led to an increase in macrofauna diversity.

This paper addresses the issue of managing the large amount of biomass straw after combining rice in India. The easiest and most common farmer way is to burn the straw so land preparation is easier, but this comes with negative environmental problems especially air pollution from the smoke. CA can be a good option since the surface straw can help improve soil health, but low temperatures and nitrogen levels slows decomposition rates, immobilizes nitrogen and hinders land preparation, although CA uses no-tillage. This paper applies fungal inoculants to enhance bacterial degraders. The paper also looks at the genomic insights for choosing appropriate decomposers. The paper talks about incorporation of straw, whereas in CA, the idea is to maintain the straw as a surface mulch and minimize soil disturbance through tillage. Just enough to sow the seed into the mulch with equipment designed to plant efficiently into the residue.