Conservation Agriculture Practices Research Articles

Community-embedded experiential learning and adoption of conservation farming practices in Eastern and Southern Africa

In low-income country agriculture, there is frequently limited information about the comparative effectiveness of alternative extension modalities for delivering information on new farming methods. This paper analyzes the impact of community-embedded farmer education programs on the adoption of conservation farming. A multinomial choice model is applied on survey data from Kenya, Malawi, Mozambique, and Tanzania to estimate the relative risk ratios (RRR), a measure of the probability of adopting the conservation agriculture practices studied, conditional on attending specific extension activities in the farmers' community. The results show that the likelihood of adoption was generally high as measured by RRRs between 10 and 14. Suggestive of the effectiveness of experiential learning methods, attending training sessions had consistently higher RRRs of adopting conservation farming practices. The positive role of community-based extension programs potentially means that the dissemination of conservation agriculture requires investments by governments and development organizations in community learning sites. Investments in programs that promote experiential, hands-on and farmer self-learning can be consequential in enabling the diffusion of better farming methods.

Determinants of conservation agriculture adoption among small-holder farmers in Gilgil sub-county, Kenya

Conservation Agriculture is a practice that enhances sustainable and intensified agricultural production. Conservation Agriculture involves; crop rotation, minimum tillage, mulching, zero tillage, maize-legume intercrop, and residue retention. Conservation Agriculture practices are crucial in providing solutions to food and nutrition insecurity, loss of biodiversity and declining soil quality in Kenya. This study documented the current status of Conservation Agriculture use in Gilgil Sub-County of Nakuru County, Kenya, reasons for adoption, and influence of socio-economic, institutional, and agro-ecological factors on adoption of Conservation Agriculture and patterns of use. The study was conducted in July 2020 in Gilgil Sub- County of Nakuru County, Kenya. The study targeted 71,268 farmers and an accessible population of 10,914 farm families respectively. Purposive and systematic sampling techniques were used to select 150 small-holder farmers based on Nassiuma formulae. Data were collected using a semi-structured questionnaire. Both descriptive (mean, frequencies, and percentages) and inferential (Multivariate probit and Tobit models and Factorial Analysis of Variance) statistics were used to analyse the data. The results revealed incomplete use of Conservation Agriculture practices: about 87% used less than five of the six recommended Conservation Agriculture practices while only 13% used five to six practices promoted in the area. This result indicates that farm-level benefits of using all Conservation Agriculture practices simultaneously were not fully realized. Second, the study established that farmers used Conservation Agriculture practices for agronomic, environmental conservation, and economic reasons. Furthermore, the differences in patterns of use of Conservation Agriculture practices were significantly determined by extension contacts, main occupation, education, access to credit, external institutional support, group membership, and land size.

Interrelation between harvester ant activity, soil fertility, and land management in the arid lands of the Negev Desert, Israel

Much of the open lands in arid areas are highly degraded reaching a state grazing or crop yields become low and non-profitable a state grazing or crop yields become low and non-profitable. Implementation of deep tilling and fertilization to enhance yields may cause destructive outcomes for the environment. An alternative approach may be conservation agriculture practices also involving the triangular interrelation among the harvester ant activity, soil fertility, and land management practices to maximize and increase the sustainable agricultural utilization of semi-arid farm land. In order to define this interrelation, a study was carried out at three sites in the northern Negev, Israel between 2014 and 2017. In each site, three different land management practices were carried out (cereal breeding, grazing, and conservation). The findings indicate that in the first three years, the harvester ants' foraging activity increased soil organic matter content by 0.25% per year, followed by an increase of 0.5 % year−1, caused by ants' nesting and foraging. In this state, partial grazing or rainfed crop breeding using a conservative tillage scheme can be carried out until sustainability. Cultivations such as fertilizing with organic matter and land management practices such as savanna trees or local perennials plantations may strengthen the interrelation among the harvester ant activity, soil fertility and biological productivity leading to an increased sustainable agriculture utilization.

Optimizing interaction between crop residues and inorganic N under zero tillage systems in sub-humid region of Kenya

Conservation agriculture practices involving zero tillage and residue retention are promising nutrient management strategies for soil health restoration. Despite their potential positive impact on soil fertility, improved crop yields and increased revenues for smallholder farmers; their effect on nitrogen inputs and crop growth is not clearly understood. This may limit their potential as a nutrient management strategy that may remedy soil degradation and boost crop yields for farmers. This study investigated how different tillage practices, crop residues and inorganic nitrogen (N) options affect maize production, soil fertility and economics of smallholder farming systems. The study was conducted in a short-term (2 years) on-station trial, under randomized complete block design with three replications in a maize monocrop system. Six treatments, involving three different rates of maize stover residue (0, 3 and 5 t ha−1) and inorganic N (0, 3 and 5 t ha−1) inputs, respectively, were assessed under conventional and zero tillage systems. Mineral N and organic C were assessed at four depths (0–10 cm, 10–30 cm, 30–60 cm and 60–90 cm) whereas soil aggregate distribution was assessed at 0–5 cm, 5–10 cm, 10–15 cm and 15–20 cm depths. Application of inorganic N as the only input increased (p ≤ 0.05) grain yield (with the yields doubling in the short rains (SR) of 2015 and increasing by 1.4 times in long rains (LR) of 2016) compared to unfertilized control treatment. Treatment, soil depth and the time of sampling significantly affected soil mineral N concentration (p ≤ 0.05). Soil organic C reduced significantly (p ≤ 0.05) with sampling depths, but no differences were observed across treatments. At 0–5 cm depth, the proportion of large macroaggregates in zero tillage increased (48%; p ≤ 0.05) after application of crop residues at 5 t ha−1 relative to 3 t ha−1. Zero tillage treatment with application of 5 t ha−1 of residue and 80 kg N ha−1 was the most dominant and most profitable compared to the other treatments. This treatment had a benefit cost ratio (BCR) of 2.9 (in the short rains season of 2015) and 3.0 (long rains of 2016 seasons). Its marginal rate of return (MRR) was 368% (in the 2015 short rains season) and 416% (in the 2016 long rains season). This makes it a good nutrient management strategy with potential of optimizing maize yields.

Soil carbon sequestration potential and the identification of hotspots in the eastern Corn Belt of the United States

AbstractSoil C sequestration is a significant CO2 mitigation strategy, but precise assessments of sequestration require spatially explicit modeling of potential changes in soil organic C (SOC) in response to soil, climate, land condition, and management interactions. We assessed the SOC sequestration potential of the eastern Corn Belt (ECB) in the United States (Indiana, Kentucky, Maryland, Michigan, Ohio, Pennsylvania, and West Virginia) in response to the adoption of conservation farming practices and land use change (pasture and forestation) using the SOCRATES model. Input data was provided through an intersection of the State Soil Geographic database, National Land Cover Database, and a PRISM (https://prism.oregonstate.edu) climate surface. At the end of the 20th century, the 15.3 Mha of cropped soils in the ECB contained 632 Tg C, an estimated reduction of 52% since the introduction of agriculture in the mid 1800s. Complete adoption of no‐tillage practices on prime cropland would potentially recover 147 Tg SOC over 20 yr, whereas a continuation of conventional tillage would produce a loss of 35 Tg SOC over that period. Sequestration hotspots (>500 Gg increase in SOC) under no‐tillage cover 2.3 Mha providing 28 Tg C over 20 yr. The conversion of marginal (nonprime) agricultural lands to forests would yield an additional 13 Tg C in SOC and 381 Tg C in aboveground biomass. The rehabilitation of minelands to forest would yield an additional 4 Tg C in SOC and 42 Tg C in biomass. Opportunities to sequester C in the ECB via tillage and reforestation are substantial and should be incorporated into regional and national climate change mitigation strategies.

Yield effects of conservation farming practices under fall armyworm stress: The case of Zambia

Conservation farming (CF) aims to achieve increased agricultural productivity while ensuring environmental sustainability through a system of agronomic practices, including minimum soil disturbance (MSD), crop residue retention (RR), and crop rotation (CR). Although inconclusive, there is some evidence that CF can improve crop yields in smallholder farming systems of sub-Saharan Africa (SSA). In this article, we examined whether the implementation of CF practices (either separately or in tandem) can offset the negative yield effects of fall armyworm (FAW), a new invasive pest that is causing devastating effects on maize in SSA. We used data from 1048 smallholder maize plots across the major maize-producing agro-ecological zones of Zambia. Results showed that 86% of the plots had at least one of the CF practices, but only 26% of the plots were under the full CF package. Factors that consistently influenced the use of the various CF packages included agro-climatic conditions, land tenure security, livestock raising and credit constraints. We found suggestive evidence that CR, when adopted in isolation or in combination with RR, can increase maize yield by up to 360 kg/ha (28%) under FAW stress. On the other hand, none of the MSD-related practices (including the full CF package) had a significant effect on maize yield. Overall, our analyses suggest that certain components of CF can mitigate short-term yield loss, but high-rainfall environments and the use of modern inputs (improved seeds and agrochemicals) are the most robust determinants of smallholder maize yields in the face of FAW invasion.

Factors affecting the placement of agricultural best management practices in the agricultural conservation planning framework (ACPF) toolbox in the mid-Atlantic region.

There has been a recent push to conduct spatially explicit landscape planning at finer hydrologic unit scales to mitigate diffuse pollution. The Agricultural Conservation and Planning Framework (ACPF) helps identify potential locations for agricultural conservation practices by using high-resolution soils and elevation data. This spatially explicit approach attempts to identify runoff and nutrient pathways, but output may be influenced by user-specified parameters and the properties of the digital elevation model (DEM) being used. Here we assess differences in the density and location of conservation practices sited by the ACPF toolbox across three DEM resolutions in three agricultural catchments, each in distinct physiographies (Ridge and Valley, Piedmont, Coastal Plain) of the United States mid-Atlantic region. Output frequency did not vary much for contour buffer strips or water and sediment control basins (WASCOBs) across DEM resolution, particularly compared with landscape type. The DEM resolution was crucial for the density of grassed waterways but of little consequence for contour buffer strips. Placement density of WASCOBs and contour buffer strips varied by region. Grassed waterways are sited based on either discrete values or statistical distributions of stream power index (SPI). A higher density of grassed waterways was placed in lower relief landscapes when a single standard deviation threshold was applied. Using discrete SPI values for the grassed waterway tool generated more consistent output across watersheds than output based on statistical distributions. These and other reported findings can help guide user decisions in future applications of the ACPF toolbox, particularly across different areas of study.

The food-energy-water-carbon nexus in a maize-maize-mustard cropping sequence of the Indian Himalayas: An impact of tillage-cum-live mulching

Amid the current environmental crises that exert enormous pressure on the arable lands, there is a need to adopt environment-friendly effective but highly productive conservation agriculture practices to feed the growing world population. Thus, a study was conducted to test the hypothesis that the inclusion of cowpea (Vigna unguiculata L. Walp) live mulch under no-till and reduced tillage in the summer maize (Zea mays L.) – rainy season maize-mustard (Brassica juncea (L.) czern) sequence would enhance agronomic productivity, energy use efficiency, and water productivity while reducing greenhouse gases emissions. Five tillage treatments viz., no-till, no-till-live mulch, reduce tillage, reduce tillage-live mulch, and conventional tillage were evaluated in three times replicated randomized complete block design. Land productivity for maize–maize–mustard system was the highest under reduced tillage-live mulch. No-till-live mulch had 36.4% lesser energy requirement, 2.4 times more energy productivity than that under conventional tillage. Reduced tillage-live mulch and no-till-live mulch had higher water productivity compared to all other treatments. The conventional tillage had the highest net CO2-eq emission while no-till-live mulch had the lowest. Inclusion of cowpea as live mulch enhanced C sequestration which has the potential to offset approximately half of the total CO2 emission, enhance energy use efficiency, land and water productivity. The findings of this study might be useful to develop a policy for sustainable high productivity through efficient resource use in the Eastern Himalayan Ecosystems that have the potential to become the corn belts of India.

Impact of long term conservation agriculture on soil quality under cereal based systems of North West India

Soil quality is of utmost essential for yield sustainability of intensive cereal based cropping system in North West Indo Gangetic plains of India. Hence, we evaluated long-term (10 years) effect of conservation agriculture (CA) practices on soil quality improvement under six different cropping scenarios (Sc), i.e. Sc1-represented by transplanted puddled rice (TPR) followed by conventional tilled broadcasted wheat (CT-wheat) with residue removal, Sc2-TPR rice followed by zero tillage (ZT) wheat and ZT-mung bean with partial residue retention, Sc3-direct seeded rice (DSR) followed by ZT-wheat and ZT-mung bean with full residue retention, Sc4-DSR is replaced by ZT-maize followed by ZT-wheat and ZT-mung bean, Sc5 and Sc6 were – Sc3 integrated with sub surface drip irrigation (SDI) and Sc4 + SDI, respectively. Soil samples were collected from 0 to 5, 5–15 and 15–30 cm soil depth from each scenario after harvesting of wheat in 2019. Results showed that, reduction in bulk density (BD), soil penetration resistance (SPR) and enhancement of water holding capacity and infiltration were associated with CA based scenarios (Sc3–Sc6). Scenario 3 recorded lowest BD of 1.39 and 1.58 g cm−3 at 0–5 and 5–15 cm soil depth, respectively. CA based Sc6 recorded highest infiltration rate (1.48 cm hr−1) and lowest was associated with Sc1 (0.5 cm hr−1). The enrichment of soil organic carbon (SOC) content, stock, available nitrogen and potassium was mainly confined to upper surface soil layer (0–5 cm). The SOC content and stock in CA based scenarios (average of Sc3 to Sc6) was 41–57 and 69–94% higher than Sc1 at 0–5 cm soil layer. Available nitrogen was increased by 23–50 and 64–98% and available potassium increased by 13–28 and 42–71% in 0–5 and 5–15 cm soil depth, respectively in CA based scenarios over Sc1. Similarly, microbial biomass carbon (MBC) and dehydrogenase (DHA) activity in top soil layer under CA based scenarios was increased by 177–195 and 67–107% over Sc1, respectively. The maximum SQI was registered with Sc6 (0.91) followed by Sc4 (0.89) and least was recorded in Sc1 (0.65) at 0–5 cm soil depth. Maize-wheat based cropping system recorded higher SQI over rice–wheat based cropping system. Sustainable yield index was strongly related with key soil quality indicators and also positively correlated with SQI. Thus our study suggests that CA based maize-wheat-mung bean cropping system should be recommended for better soil quality and yield sustainability in North West India.

Water budgeting in conservation agriculture-based sub-surface drip irrigation in tropical maize using HYDRUS-2D in South Asia

In water scarce regions of South Asia, diversification of rice with maize is being advocated towards sustainability of cereal-based cropping systems. Adoption of innovative agronomic management practices, i.e., conservation agriculture (CA) and sub-surface drip irrigation (SSDI) are considered as key strategies for much needed interventions to address the challenges of water scarcity under projected climate change. Benefits from CA and SSDI concerning water economy are well-established, however, information about their complementarity and water budgeting in cereal-based systems are lacking. A field study was conducted with process-based model (HYDRUS-2D) to understand water transport, root water uptake and components of soil water balance in maize grown in rotation with wheat after five years of continuous adoption of conservation agriculture. In this study, altogether eight treatments comprising of 6 CA+ treatments (CA coupled with SSDI); permanent beds using sub-surface drip (PB-SSD) with (WR) and without (WOR) crop residue at different N rates, 0, 120 and 150 kg N ha−1 were compared with CA (PB using furrow irrigation-FI with crop residue-120 kg N ha−1) and conventional tillage practices (CT) (CT using FI without crop residue-120 kg N ha−1). Results showed that the model could simulate the daily changes in profile soil water content with reasonable accuracy in all the treatments. Simulated soil water balance indicated higher cumulative root water uptake (CRWU), lower cumulative evaporation (CE) and higher soil water retention in CA+ (PB-SSD+ crop residue at 150 and 120 kg N ha−1) than CA and CT plots. Hydrus-2D model efficiency > 0, RMSE between 0.009–0.026 and R2 value between 0.80–0.92 at P < 0.01 indicates that the model is performing efficiently. The mean evaporation from CA+ treatments was 10 and 36% less than CA and CT treatments, respectively. On average, CRWU under CA+ treatments were 14–48% higher than FI treatments. The mean cumulative deep drainage in CA+ plots was 80–100 mm less than CA and CT plots. In CA+ based plots significantly higher biomass production and radiation use efficiency were observed with reduced water use than CA and CT. Therefore, the study justifies the water-saving nature of CA+, while maintaining higher productivity and meeting the transpiration demand of crops and halting unnecessary evaporation and deep drainage losses.

Cadmium accumulation in rice straws and derived biochars as affected by metal exposure, soil types and rice genotypes

Straw residues, as one of the conservation farming practices, are being strongly encouraged in China, including some cadmium-polluted areas. Nowadays, a portion of this plant residue is promoted to be removed for reducing excess metal(loid) in the soil and to be used for bioenergy production. Nevertheless, the possible influences of contaminated straw or the burial of its derived biochars on Cd accumulation in soil and data based on health risk assessment associated with different status and extent of soil contamination were relatively unknown. Thus it is important to provide a more systematical understanding of contaminated straw burial at specific contamination zones, which may provide useful guidance for straw utilization. In this study, we harvested two genotypes of rice straw from 6 contaminated levels among three soil types to comprehensively study the total Cd contents in straws and its derived biochars and correlate the sets of straw characteristics and Cd contents in three different contamination zones. The total Cd concentration in straws grew at a steady rate relatively with increasing soil Cd contamination levels, compared to those in biochars which performed more fluctuate due to the strong burning. According to correlational analyses, three-way ANOVA showed that the moisture, ash, volatile and fixed carbon were all significantly affected by straw CdTotal contents (p < 0.001). Such relationships were attributed to guide straw removal portions for gasification. Meanwhile, there was a significant correlation between straw Cd concentration and soil types (p < 0.001), confirming that it might be worth determining soil remediation by straw removal according to site-specific farmland conditions. This work will help to assess efforts toward predicting Cd concentration in the paddy soils related to kinds of contamination status and would also give useful guidance to make sustainable management strategies for crop straws in polluted regions. Novelty statement This work provided data on how much rice straw is needed to remove to ensure the minimal amount to control soil contamination and reduce costs according to site-specific conditions and soil Cd contamination status. It also explains the correlations between straw characteristics related to bioenergy use and soil conditions which would give guidance to balance using crop straw for increased bioenergy production and the need to also protect, preserve, and enhance soil resources.

Quantification of resilience metrics as affected by conservation agriculture at a watershed scale

It is suggested that conventional tillage operations exacerbate global environmental changes and affect the sustainability of our food production systems. Therefore, no-till has been introduced as one of the conservation agriculture practices to counteract these challenges. No-till has been adopted by a substantial number of farmers in major cropping regions; however, its resilience from large scale implementation has been overlooked. The majority of the studies have reported only a few aspects of the no-till practice (e.g., yield, soil properties, etc.), often with contradicting observations. To fill this gap, we present an approach that integrates long-term field experimental data and modeling to quantify resilience at a watershed scale. The study was conducted in the Kalamazoo River watershed located in Michigan, USA. Recharge, groundwater table, soil moisture, yield, and net return were used as resilience metrics. The DSSAT sequence crop model was developed for a corn-soybean-wheat rotation and calibrated using the yield and soil moisture data from a long-term (1993–2019) experiment for the conventional and the no-till treatment conducted within the study area. Soil moisture, recharge and yield were simulated, and the recharge was fed into a calibrated groundwater model to analyze changes in groundwater heads. The results illustrate clear evidence of higher recharge and net return under the no-till treatment, which were statistically significant for all crops at the watershed scale. Moreover, the no-till treatment consistently retained greater soil moisture than the conventional treatment, thereby helping to mitigate the impacts of droughts. The rise in groundwater table as affected by the adoption of no-till practices in this watershed has ranged between 0.1 and 0.5 m, depending on the underlying groundwater system, and has the potential to beneficially affect the aquifers and groundwater-dependent ecosystems. Therefore, the conservation agriculture could improve the overall resilience of the row crop system.

Conservation management decreases surface runoff and soil erosion

Conservation management practices – including agroforestry, cover cropping, no-till, reduced tillage, and residue return – have been applied for decades to control surface runoff and soil erosion, yet results have not been integrated and evaluated across cropping systems. In this study we collected data comparing agricultural production with and without conservation management strategies. We used a bootstrap resampling analysis to explore interactions between practice type, soil texture, surface runoff, and soil erosion. We then used a correlation analysis to relate changes in surface runoff and soil erosion to 13 other soil health and agronomic indicators, including soil organic carbon, soil aggregation, infiltration, porosity, subsurface leaching, and cash crop yield. Across all conservation management practices, surface runoff and erosion had respective mean decreases of 67% and 80% compared with controls. Use of cover cropping provided the largest decreases in erosion and surface runoff, thus emphasizing the importance of maintaining continuous vegetative cover on soils. Coarse- and medium-textured soils had greater decreases in both erosion and runoff than fine-textured soils. Changes in surface runoff and soil erosion under conservation management were highly correlated with soil organic carbon, aggregation, porosity, infiltration, leaching, and yield, showing that conservation practices help drive important interactions between these different facets of soil health. This study offers the first large-scale comparison of how different conservation agriculture practices reduce surface runoff and soil erosion, and at the same time provides new insight into how these interactions influence the improvement or loss of soil health.

Carbon and nitrogen accumulation in soils under conservation agriculture practices decreases with nitrogen application rates

In intensively managed agricultural systems, fertilizer management has great impact on the size and activity of microbial functional communities. However, the effects are not clear due to the variability of soil type, climate and cropping diversity. We have investigated microbial biomass and enzyme activities in soils under seven consecutive years of strip (ST) and conventional tillage (CT), high (HR) and low (LR) levels of residue addition, and three N fertilization rates in a wheat (Triticum aestivum)-mung bean (Vigna radiata)- rice (Oryza sativa) crop rotation. Nitrogen rates of each crop were in agree to the recommended dose (RD) or 60% RD or 140% RD. The interaction effects of tillage, residue retention and N rates showed higher potential for lower N rate (60RD) in ST with HR sequestering more carbon. Likewise, the highest total N content was found at 60RD in ST, with HR being higher than 140RD but similar to 100RD. Increased N application rates above recommended dose reduced the MBC content and dehydrogenase and β-glucosidase activities but it enhanced urease activity. Negative relationships between N application rates and MBC, dehydrogenase and β-glucosidase and positive relationship with urease activities suggest that higher N application suppresses C and N buildup in soils.

​Conservation Agriculture (CA)-Based Tillage Practices in Maize for Enhancing Crop Yield, Resource use Efficiency and Soil Health: A Review

The triple challenge of acute water crisis, stagnant crop yield and soil health deterioration in NW Indo Gangetic Plains (IGP) ramble a search for potential alternative crop establishment technique (CET). Hence, maize-based crop rotations under best-bet conservation agriculture (CA) practices can plays a critical role in sustainable crop production. The CA-based tillage and CET viz. zero tillage (ZT) and permanent raised beds (PB) hold potential to intensify crop yield per hectare, improving resource use efficiency besides bringing desirable changes in soil physico-chemical and biological properties. Therefore, it needs to be popularized in larger scale chiefly under maize-based rotation to makes farming more attractive, profitable and sustainable.

Extension services as key determining factor for adoption of minimum tillage practice in Kenya: A plot level analysis

There is a consensus that conservation agricultural practices increase crop productivity and save resources. However, even after a decade of active promotion of conservation agriculture in sub‐Saharan Africa, the adoption of such practices as minimum tillage is low. This article finds out the determining factors that influence the adoption decision of smallholder farmers of Kenya about minimum tillage practice. The study is based on survey data from a randomly collected sample of 300 households in the maize‐dominant farming system of eastern Kenya. A plot‐level analysis consisting of 437 plots is carried out using the Probit regression to estimate the adoption decision model. Access to extension information is found to be a key determinant of adoption decisions for minimum tillage. 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 farmers' decision to adopt minimum tillage practice. Extension services being a vital element in the efforts to promote minimum tillage practice, more effective implementation of promotion programs need to be undertaken by the Government in Kenya in particular and sub‐Saharan Africa in general.

​Conservation Agriculture Practices: Impact on Productivity, Energy Utilisation and Profitability of Legume-based Cropping System

Background: Conservation agriculture (CA), an agricultural production system with optimum inputs, high returns and sustainability while conserving environment is primarily required for command areas and rainfed uplands. CA helps to improve and conserve soil health through crop rotation, mulching, minimum field traffic and mechanical soil disturbance etc and conserve water to achieve economically and ecologically sustainable crop production. Methods: The field experiment was conducted for two years during 2019-21 to evaluate the influence of conservation agricultural practices on the system productivity, production efficiency and energy use under legume based cropping system in a command area. Treatments comprised of four cropping systems as Groundnut - foxtail millet (C1), Groundnut - barnyard millet (C2), Daincha - foxtail millet (C3) and Daincha - barn yard millet (C4) in main plots and foliar application of organics, 3% panchagavya, 1% PPFM and 0.1% humic acid formed subplots. Result: System productivity in terms of Groundnut equivalent yield (GEY) was significantly higher (8395 kg/ha) in the Groundnut - Barnyard millet cropping system with foliar application of PPFM 1% in CA system than that of conventional method. The production efficiency was maximum in Groundnut - barnyard millet system (34.41 kg/ha/day) and Groundnut - foxtail millet recorded the highest energy use efficiency (6.8%) which shows that maximum energy was effectively utilized under the system. Daincha - foxtail millet system had highest energy productivity of 0.91 kg M/J. Thus, the conservation tillage based Groundnut - barnyard millet system recorded more system productivity, highest resource use efficiency (both production and land use efficiency) and the highest energy use efficiency.

Quantifying the impact of no‐till on sediment yield in southern Brazil at the hillslope and catchment scales

AbstractNo‐till (NT) is a soil management system designed to protect soil resources from water erosion and provide numerous benefits compared to conventional tillage through the increase of organic matter inputs into the soil. However, NT in isolation is not sufficient to control erosion processes caused by an excessive production of surface runoff. This study evaluated soil losses on agricultural hillslopes under no‐till characterized by contrasted water, soil, and crop management conditions. To this end, water and soil losses were monitored between 2014 and 2018 at two scales, including four macroplots (0.6 ha; 27 events) and two paired zero‐order catchments (2.4 ha; 63 events). The resulting dataset covered a wide range of rainfall conditions that occurred in contrasted soil, crop, and runoff management conditions. Hyetographs, hydrographs, and sedigraphs were constructed, and these data were used to evaluate the impact of management on sediment yields, including that of terraces, scarification, and phytomass on sediment yield. The installation of terraces reduced sediment yield by 58.7%, mainly through surface runoff control. Crop management including an increased phytomass input efficiently controlled soil losses (63%), although it did not reduce runoff volume and peak flow. In contrast, scarification had no impact on runoff and soil losses. The current research demonstrated the need to combine the installation of terraces and leaving a high amount of phytomass on the soil to control surface runoff and erosion and reduce sediment yield. The current research therefore reinforces the relevance of the monitoring strategy conducted at the scale of macroplots and zero‐order catchments to evaluate the impact of contrasted water, soil, and crop management methods and select the most effective conservation agriculture practices.

Assessment of Dietary Bioactive Phenolic Compounds and Agricultural Sustainability of an African Leafy Vegetable Corchorus olitorius L.

Corchorus olitorius L. is an African leafy vegetable of high nutritional interest. To assess its agricultural suitability to sustainable cultivation conditions and its potential benefits for human nutrition, its phytochemical content in response to conservation agriculture practices [i.e., no-tillage (NT) and cover crop maintenance] and low water regime were evaluated and compared with response under conventional agriculture management. Hydric stress and NT did not affect the content of antioxidant metabolites, compared to conventional agricultural practices. In both conditions, leaves were found to be a great source of phenolic compounds. The effect of these phenolic fractions was assessed on two colon cell phenotypes to evaluate putative nutraceutical properties. Polyphenol-enriched extracts (PEEs) displayed selective cytotoxic activities against tumor Caco-2 cells but not on the healthy CCD841 line. PEEs were able to trigger oxidative stress and to inhibit the activity of glutathione-independent antioxidant enzymes on Caco-2 cells. C. olitorius showed to be a promising crop for improving both agricultural sustainability and health benefits due to the great amount of antioxidant compounds in leaves, whose occurrence is not altered by stressful farming conditions. Given its high adaptability, the cultivation of this crop is therefore recommendable also in the Mediterranean Basin.

Conservation agriculture-based Zea mays (maize)-Phaseolus vulgaris (common bean) cropping systems in South Central Ethiopia

Conservation agriculture (CA) is defined as sustainable agriculture production system comprising a set of farming practices. The experiment was conducted at three districts from 2011 to 2016 at five farmers’ field they considered as replicate. The experiment consisted of five treatments (continuous sole maize, maize bean rotation, maize-bean inter-cropping, bean rotation under CA and farmer practice). Maize yield and yield related traits and soil water data were collected from each site. Soil moisture content under CA practices was higher than the farmer practice. At East-Badawacho and Meskan grain yield was higher by 4 and 8% in CA compared with farmer practice, respectively. Maize bean rotation and sole maize under CA out yielded the farmer practice by 13 and 4%, respectively but inter-cropping had 5% lower grain yield. At Hawassa-Zuriya, CA maize bean rotation had higher yield than farmer practice in 2011 and 2013. Maize-bean inter-cropping, maize bean rotation and sole maize under CA had 10, 8 and 6% higher grain yield than farmer practice, respectively. Common bean grain yield from bean rotation under CA had 2799, 2908, and 3226 kg ha-1, from inter cropping bean grain yield of 817, 1065 and 927 kg ha-1 obtained at East-Badawacho, Hawassa-Zuriya and Meskan districts, respectively. Generally, CA cropping systems had drought stress reduction potential and greater yields compared with farmer practice. Key words: Farmer-practice, sole-maize, rotation, inter-cropping, rift-valley.