Conservation Agriculture Research Updates - March 2026

The specific objective of this study was to develop soil quality indices with key soil physical, chemical and biological indicators under the conservation and conventional tillage practices in a rice–mustard systems in NW India. Eight treatment combinations including tillage and crop establishment, crop residue and cropping system intensification with inclusion of short duration summer mungbean were used. The highest SQI was obtained in the zero till direct seeded rice (ZTDSR) – zero till mustard (ZTM) –ZT summer mungbean (ZTSMB (+R). They conclude that the medium-term CA with triple or double zero tillage with crop residue retention maintains agricultural sustainability under the rice-mustard system and can be recommended to farmers for adoption.

Reduced nutrient mineralization rates under NT are usually compensated for by addition of mineral fertilizer, but this is not allowed in organic systems. This paper looked at an organic NT system based on cover cropping to overcome the above problem in NT in two long-term experiments. They also looked at compost addition versus mineral P and K fertilizer. Across both experiments, macronutrients (+52%), micronutrients (+11%), microbial biomass (+51%), microbial activity (+86%), and bacterivorous nematodes (+112%) increased in NT compared to CT systems. They conclude that soil fertility can be improved in organic NT systems, with cover cropping and dead mulch, over plow-based systems.

The objective of this study was to assess the changes in soil physicochemical and microbiological parameters between four different agricultural practices from a 7-year experiment using two seasons with contrasting soil water content. They compared conventional tillage with maize (CTM); no-till with maize (NTM); no-till with maize and soybean rotated (NTM/S); no-till with annual rotation of maize intercropped with Brachiaria rhuziziensis and soybean monoculture (NTMB/S) compared to a long-term fallow (>40 years secondary forest) in both winter (rainy) and summer (dry) seasons. In sum, they show that the benefits of conservation agriculture for soil quality in this region were most obvious in the summer and depended on the agricultural practices, with NTMB/S showing the greatest conservation of soil physicochemical quality.

Challenges that have arisen with the adoption of NT include soil compaction, weed management, and stratification of organic matter and nutrients. As an attempt to overcome these challenges, occasional tillage (OT) has been used as a soil management practice in NT systems. The objectives of this meta-analysis were: 1) to summarize the effects of OT on crop productivity, soil physical, chemical and biological properties, soil erosion and weed control; 2) to discuss the main aspects of NT management to optimize the use of OT; 3) to point out shortcomings in the diagnosis of soil compaction in NT systems, which may lead to erroneous decision-making processes regarding the use of OT. They conclude that proper NT implementation and management, with the correct application of NT principles, will overcome problems associated with NT. As soil compaction is the main justification for the use of OT, methods of diagnosis and monitoring of soil compaction should be improved to assist in decision-making.

This paper looks at ways to minimize the negative affects of continuous puddled rice transplanting by looking at alternative ways to establish rice and their effects on soil health, crop productivity, resource saving and global warming mitigation potential. Innovations in machinery especially for smallholder farms have supported the adoption of the new establishment techniques. They conclude that no single rice establishment technology is superior to others in all circumstances, rather a range of effective technologies that can be applied to different agro-climates, demography and farm typologies.

This 4-year study objectives were (a) monitoring the changes in soil physical, biological and chemical properties and crop productivity, (b) development of a soil quality index-(SQI), and to monitor SQI changes against system productivity as a management goal, and (c) studying the changes in soil organic carbon-SOC in relation to annual C input. The 3 tillage practices were ZT, Permanent Beds (PB) and CT with 4 nutrient management treatments under a continuous maize-wheat-mungbean system in NW India. They conclude that adoption of CA with SSNM and Ad-hoc nutrient management in intensive cereal based systems of NW-IGP is essential for improving nutrient cycling, soil quality, crop productivity and C-sequestration potential.

Continuous rice-wheat with tillage and conventional management has led to a decline in soil health, groundwater table and farmer profits in South Asia. This study used a participatory farmer research trial to evaluate CA for reversing this degradation. 6 treatments compared various cropping systems, tillage`, crop establishment and residue management. The paper looks at the effect on yield, water productivity and net returns. Soil chemical and biological properties were also recorded. CA-based treatments were better than conventional treatments for all these measurements.

This study looked at conventional (CT) and No-till (NT) in wheat/maize following puddled  or non-puddled TP rice or direct seeded rice. Also residue removal or retention. They looked at soil aggregation, carbon pools, nutrient availability and yield. After 6 years in top 20 cm soil, NT treatments had had more total organic carbon than CT treatments. NT treatments also had more stable soil aggregates. Retention of residues increased TOC,  and soil available nutrients, especially P, K and Zinc over residue removal. The conclude that NT with residue retention should be recommended for improving soil quality and production sustainability.

The paper reports the results of the duration of CA adoption on soil carbon dynamics and system sustainability on farm in 30 villages in Karnal District of India. Soil samples were taken from existing CA  and CT farms. Looked at soil physical, chemical and biological properties. The paper concludes that farmers in Karnal district should be encouraged to adopt CA practices as they can increase SOC and move the systems from “sustainable with high input” to “sustainable”.

This study uses Collembola numbers as a good indicator of improved soil properties following a change in land management. They looked at these springtail populations in systems with a history of CA and crop-livestock use in South Brazil. The samples were also evaluated for soil chemical, physical and microbiological properties. CA and CLI management varied in the association of different Collembola's -- epigeic in CA and hemiedaphic and edaphic ones in CLI but these differences were related to different soil conditions. They conclude that Collembola community structure and species diversity were modified by the soil management systems and suggest that the Collembola community may indicate changes across land management systems in conservation agriculture.

This study looked at best management practices involving tillage and residue management to obtain improved soil health for the important rice-wheat cropping system of South Asia. Their soil quality index was based on soil physical, chemical and biological properties. They looked at  conventional practices with transplanted rice followed by broadcast, tilled wheat versus zero-tilled, direct seeded rice followed by ZT wheat. The highest rice equivalent yield of 12.41 t ha-1 was observed at SQI values of 0.90 at 0-10 cm and 0.86 at 10-20 cm in the ZTDSR fb ZT wheat. They conclude that crop residue retention on the surface with zero tillage is beneficial for the sustainability and productivity of the RWCS in EIGP of India.

This study, reported the results obtained during a 2-year field experiment of a 7-year experiment started in 2010–2011, combining two tillage practices (Conventional Tillage (CT) and Zero Tillage (ZT)) with two crop sequences (Wheat monocropping (WW) and Wheat-Faba bean (WF)) in Italy. Soil Quality (SQ) was monitored through the selection of some chemical, physical, and biological indicators measured by both visual–Visual Soil Assessment (VSA)–and standard field or laboratory measurements. They conclude that under dry Mediterranean areas, ZT practices, especially when combined with the other conservation principles (i.e., crop rotation), ameliorate several SQ indicators already even after a 7-year period of adoption, allowing a positive trend for soil preservation.

This paper contends that to meet future food needs, soil organic carbon needs to be preserved. This review examines the literature published worldwide over the last 30 years to assess the impact of one widely applied agricultural management system, conservation agriculture (CA), on its ability to maintain SOC and the subsequent impacts on soil physical, chemical and biological properties, and yield. The paper concludes that farmers require access to a range of tools and resources to allow them to identify if the principles of CA are likely to be appropriate for their situation and well-designed, locally adapted systems to successfully overcome the agronomic, social and economic challenges that can be associated with its use.

This paper used a NT System Participatory Quality Index (PQI) that requires the participation of farmers to assess key soil quality attributes associated with the implementation of the PQI methodology during a large scale dissemination of a NTS campaign in Brazil. Farmers often fail to adopt all the principles of NTS; therefore, the system requires a quality measurement. A classification system to help farmers and agricultural professionals make good soil management decisions was proposed. The tool was trialed on 40 areas of farmland under different farm systems in a Paraná River Watershed. The NTS Participatory Quality Index (PQI) was used to successfully evaluate soil management quality.

This paper looks at tillage, crop residue and N-management in the high-slope mountains of Ecuador where high rainfall causes significant soil erosion. In the initial phase 3 out of the 4 crops NT had the highest yields. Later, with addition of N fertilizer, yields were higher in 4 out of 5 crops not fertilized. Leaving the crop residue on the surface increased the yield of one crop. Higher net returns were found with NT compared to tillage.