Search

A network of agronomists, researchers, and practitioners associated with cacao farming provided open access to their independent field trials across Latin America and the Caribbean (LAC). A centralized dataset was assembled using qualitative and quantitative data from 25 experimental field trials (hereafter referred to as “CacaoFIT”) spanning several LAC agroecosystems. This dataset was used to document the main traits and agroclimatic attributes of the cacao cultivation model being tested within the CacaoFIT network. By synthesizing data from an entire network of cacao trials, this study aimed to highlight specific design features and management practices that may contribute to better cacao farming sustainability. The CacaoFIT network comprises 200 ha of field trials testing over 150 cacao genotypes and set up under dierent shade canopy design, management, and research goals. Small-sized trials were common across Mesoamerica, whereas medium to large-size trials were distinct to South America. Cacao trials were 15 years old (on average) and ranged from 3 to 25 years of establishment. Most cacao trials were managed conventionally (i.e., 55%), while 20% were under organic practices, and the remaining 25% presented both conventional and organic management approaches. Most field trials (ca. 60%) planted an average of 10 international clones or national cultivars at high (1,230–1,500 plants ha−1 ) and medium density (833–1,111 plants ha−1 ). Mixed shade canopies were the dominant agroforestry model, while timber vs. leguminous shade canopies were also common. The diversity and depth of research domains examined across the CacaoFIT network varied widely. Agronomy and agroforestry topics dominated the research agenda across all trials, followed by environmental services domains. Cacao physiology and financial performance were researched to a lesser extent within the network. Five featured field trials from CacaoFIT oered technical guidelines to inform cacao farming within similar contexts. This collaborative work is a scaold to encourage public–private partnerships, capacity building, and data sharing amongst cacao researchers across the tropic [ABSTRACT FROM AUTHOR]

Increasing pressure on arable land related to climate change mitigation and adaptation within recent policy frameworks has generated widespread interest in the effect of sustainable agricultural management practices on soil organic carbon (SOC) storage. Current frameworks point to soil microorganisms and their functioning as the key drivers of SOC accrual. This study provides a comprehensive on-farm assessment of changes in SOC formation pathways (physico-chemical and microbial) and the underlying drivers comparing three soil use systems: conservation and conventional farming systems as well as permanently vegetated adjacent reference soils (i.e., field margins) without agricultural land-use.Overall, our results indicated substantial increases in extractable organic carbon (+22 %), microbial biomass carbon (+29 %) and necromass carbon stocks (+11 %) in soils of conservation farming systems as compared to conventional farming systems. Differences between all three soil use systems were strongly pronounced in the surface soil (0–5 cm) and declined in deeper soil layers. Structural equation modelling revealed a varying influence of SOC storage pathways among soil use systems, with microbial-mediated (‘in-vivo’) turnover and direct sorption being the most dominant pathways. Moreover, diversity of crop rotation and tillage intensity were identified as the most important factors influencing extractable organic carbon and carbon-liberating enzyme activity within conservation farming management. Our on-farm approach demonstrates that enhanced bioavailable carbon inputs and reduced soil disturbance are the key drivers for microbially-controlled SOC accrual in arable soils and that conservation farming systems with extended plant coverage and increased crop diversity can substantially advance the restoration of soil health.

Background: Integrated pest management (IPM) uses thresholds to minimize pesticide use, and field monitoring of damaging organisms is an important component to evaluate whether or not thresholds have been breached. However, monitoring requires time and knowledge which impacts costs and benefits. In this study, we evaluated the effects of using insect pest thresholds on time effort, frequency of insecticide treatment and economics in comparison with common farm practices (business as usual) in winter wheat (WW), winter barley (WB) and winter oilseed rape (OSR). This study was done over 2 years (2018 to 2020) on 24 conventionally managed farms in North Rhine‐Westphalia (Germany). Results: Farmers spent significantly more time (42 min ha−1/season) monitoring insect pests in OSR than in WW (16 min ha−1/season) and WB (19 min ha−1/season). The use of insecticides in OSR was significantly reduced by 42% in comparison to business as usual. In cereal crops, the use of insecticide treatment was reduced by 50% but this was not significantly different to business as usual. Yields were not significantly reduced when crops were managed in accordance with IPM, and negative differences were small and not significant. However, economically, the costs of monitoring can only be recovered when labor costs and commodity prices are low and insecticide cost is high. Conclusion: Insect pest thresholds can help link the policy and environmental goals of insecticide reduction and the agronomic goal of production security. In the future, the time and cost required for monitoring should be reduced through intelligent solutions and tools, increasing the economic viability of monitoring and IPM. © 2023 The Authors. Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

A network of agronomists, researchers, and practitioners associated with cacao farming provided open access to their independent field trials across Latin America and the Caribbean (LAC). A centralized dataset was assembled using qualitative and quantitative data from 25 experimental field trials (hereafter referred to as “CacaoFIT”) spanning several LAC agroecosystems. This dataset was used to document the main traits and agroclimatic attributes of the cacao cultivation model being tested within the CacaoFIT network. By synthesizing data from an entire network of cacao trials, this study aimed to highlight specific design features and management practices that may contribute to better cacao farming sustainability. The CacaoFIT network comprises 200 ha of field trials testing over 150 cacao genotypes and set up under different shade canopy design, management, and research goals. Small-sized trials were common across Mesoamerica, whereas medium to large-size trials were distinct to South America. Cacao trials were 15 years old (on average) and ranged from 3 to 25 years of establishment. Most cacao trials were managed conventionally (i.e., 55%), while 20% were under organic practices, and the remaining 25% presented both conventional and organic management approaches. Most field trials (ca. 60%) planted an average of 10 international clones or national cultivars at high (1,230–1,500 plants ha−1) and medium density (833–1,111 plants ha−1). Mixed shade canopies were the dominant agroforestry model, while timber vs. leguminous shade canopies were also common. The diversity and depth of research domains examined across the CacaoFIT network varied widely. Agronomy and agroforestry topics dominated the research agenda across all trials, followed by environmental services domains. Cacao physiology and financial performance were researched to a lesser extent within the network. Five featured field trials from CacaoFIT offered technical guidelines to inform cacao farming within similar contexts. This collaborative work is a scaffold to encourage public–private partnerships, capacity building, and data sharing amongst cacao researchers across the tropics.

Simple Summary: On-farm research that investigates commercially relevant climate-smart conservation practices is critical in order to develop practical sustainability strategies in agricultural production systems. The purpose of this study was to investigate on-farm methane (CH4) mitigation potential and animal health outcomes using a commercially available tannin as a feed additive in dairy heifers reared under an organic production system. Enteric CH4 was measured using one GreenFeed and animal health was evaluated via select antioxidant enzyme and oxidate stress biomarker concentrations. No effect was observed for daily enteric CH4 production, average daily gain (ADG), dry matter intake (DMI), or oxidative stress biomarker concentration. Tannin supplementation did have an effect on the concentration of the antioxidant-enzymes-reduced glutathione (GSH) and superoxide dismutase (SOD). Future research may consider the investigation of animal health benefits due to tannin supplementation, such as linking the effect of tannins to the improved antioxidant status of heifers, which may be of particular interest in organic dairy production systems. The observations from this study highlighted the challenges for future on-farm sustainability research and the scalability of potential CH4 mitigation strategies. The objective of this experiment was to demonstrate the effectiveness of a commercially available tannin product (Silvafeed® ByPro, 70% tannic acid) as an enteric methane (CH4) mitigation and preventative animal health strategy in Holstein heifers (BW = 219 ± 17 kg; 9 mo), reared under organic production system requirements. Twenty heifers were randomly assigned to one of four commercial tannin supplementation treatments as follows: 0% (0 g/hd/d; CON), 0.075% (~5 g/hd/d; LOW), 0.15% (~10 g/hd/d; MED), and 0.30% (~21 g/hd/d; HIG) of dry matter intake (DMI). Heifers received their treatment in individual animal feeding stanchions and were fed a basal total mixed ration (TMR) through four SmartFeed Pro intake measurement bunk systems (C-Lock Inc., Rapid City, SD, USA) for 45 d. An automatic head chamber system (AHCS; i.e., GreenFeed, C-Lock Inc., Rapid City, SD, USA) was used to continuously evaluate enteric CH4 production. No effect was observed among the treatments for CH4 emissions (p ≥ 0.55), animal performance (p ≥ 0.38), or oxidative stress biomarker concentration (p ≥ 0.55). Superoxide dismutase (SOD) and reduced glutathione (GSH) concentrations exhibited a linear response to increasing tannin dose (p = 0.003), indicating a potential tannin effect on the antioxidant status of dairy heifers. This observation may encourage future tannin research relating to animal health, which may be of particular interest to organic dairy systems. The results of this study suggest that tannin supplementation at 0%, 0.075%, 0.15%, and 0.30% of DMI, did not alter CH4 emissions, animal performance, or oxidative stress biomarker concentration in organic Holstein heifers when assessed under an on-farm research approach. Further, the results of this study affirm the challenges associated with on-farm research and the development of climate-smart strategies that are capable of mitigating climate impacts in less controlled environments under standard working conditions. [ABSTRACT FROM AUTHOR]

The digitisation of agriculture is underway—with advocates highlighting its potential to improve resource efficiency and reduce environmental impacts of agriculture, and critics suggesting that emerging technology will exacerbate inequalities in the food system. Drawing on five years of collaboration within an interdisciplinary sustainable agriculture project, I critically consider the limitations of on-farm research as a strategy for rendering 'real-world' farm practice into data for digital tools to guide farmer decision-making. In engagements with data science, anthropologists must use our seat at the table to practice what Helen Verran (2001) called 'generative critique' in support of responsible research and innovation. Our training in engaged yet critical participant observation, and our experience building long-term relationships within communities, makes anthropologists particularly well-suited for this role. [ABSTRACT FROM AUTHOR]

Abstract There are growing concerns over the failure of attempts to confirm findings from past studies in various disciplines, and this problem is now known as the “reproducibility crisis” or “replication crisis”. In the agricultural sciences, this problem has remained unappreciated, underreported and there are deficiencies in efforts to tackle it. According to a recent analysis, it is difficult to reproduce on-farm experiments due to the lack of research transparency. Non-reproducible research does not only waste resources, but it can also slow down scientific progress and undermine public trust. In this commentary, my aim is to draw attention to the evolving concepts and terminology used in characterizing reproducibility and the common reasons for non-reproducibility of past research. I argue that analytic transparency is not only key for reproducibility of research but it can facilitate systematic reviews, meta-analyses and evidence mapping to guide formulation of evidence-based policies and practices.

Soil acidification is a major problem in the inland Pacific Northwest. A potential solution is the application of lime to neutralize acidity and raise pH. As lime is an expensive input, precision variable rate application is necessary. However, high-resolution mapping of pH and buffer pH for lime prescription requires costly sampling and analysis. To reduce the amount of sampling needed, remote sensing, which correlates with soil pH and buffer pH, can be used to determine optimal sampling locations and allow optimal interpolation. We used soil and crop data from the Washington State University R.J. Cook Agronomy Farm to develop an optimal sampling plan for a farmer's property, followed that sampling design, and used the measured pH and buffer pH to fit a Bayesian hierarchical model using remote sensing variables specific to that farmer's land. Following this, a new model was developed for the research farm with similar covariates. Ultimately, on the farmer's field, we observed a root mean square error (RMSE) of 0.2487 for soil pH at a depth of 0–10 cm and 0.1221 for modified Mehlich buffer at 0–10 cm of depth. For the research farm, where buffer pH was not measured, we saw an RMSE of 0.3272 for soil pH at 0–10 cm of depth and 0.3381 for soil pH at 10–20 cm of depth. The ability make predictions of soil acidity with uncertainty using this technique allows for prescription lime application while optimizing soil sampling and testing. Further, this paper serves as a case study of on-farm research. [ABSTRACT FROM AUTHOR]

Background: Goat production has grown worldwide as a way to improve the quality of rural life and reduce the environmental footprint; nevertheless, there is a need to increase productivity through improved feeding strategies. The market demands healthier products with organoleptic characteristics similar to the traditional ones; thus, it is necessary to evaluate the effect of new forages for goats and its acceptance by consumers. Chemical and organoleptic composition of goat milk vary according to the diet which, in turn, affects the characteristics of cheese. Cheese texture, taste and smell are the most important sensory attributes for consumers. Objective: To evaluate the effect of substituting corn straw with sunflower hay associated with chickpea for dairy goats on yield, chemical composition and sensory acceptability of cheese, as well profitability. Methods: Twenty-eight Saanen dairy goats were randomly assigned to two treatments in a 30-day experiment on a small farm. The daily ration per goat in the MZST treatment (control treatment) consisted of alfalfa hay (200 g/goat/day) and concentrate (400 g/goat/day) plus 600 g/goat/day (50% of the ration) of corn straw. The SFCP treatment substituted corn straw with sunflower-chickpea hay; it had the same alfalfa and concentrate content, but with no corn straw and was added with 600 g/goat/day of sunflower-chickpea hay. The yield, composition and sensory evaluation of fresh cheese made with milk from each treatment were recorded, and the feeding costs and returns evaluated. Variables for the chemical composition of cheese were analyzed following a completely randomized design. Results: Significant differences were observed in cheese yield and all chemical composition variables. According to sensory evaluation, SFCP cheese had significantly higher scores for texture and odor but lower for taste and overall acceptability compared to MZST. In terms of profitability, SFCP increased feed costs by 5% but resulted in higher margins over feed costs of 12 and 24% for milk and cheese, respectively, compared to MZST. Conclusion: In spite of favorable performance and economic returns of MZST treatment (control treatment), the organoleptic characteristics of the cheese reduced its general acceptance. [ABSTRACT FROM AUTHOR]

In the context of sustainable practices and European strategy to reduce the chemical inputs in agricultural conventional systems, on field crops there are approached agroecological practices that targets the performance growing through effective measures that adjust the biodiversity of agroecosystems. The study presents the results of a field experience developed in a farmer participative approach on two years (2021, 2022). In his farm - from Buești, Ialomița, Romania - were established 30 multifactorial testing varieties composed from treatment with a special product for maize crop (BioZeaFert: BF) from Bacillus subtilis ICCF 84: 25%; Bacillus subtilis 284: 25%; Trichoderma harzianum ICCF 179: 50%. The treatments have been applied on seeds (Untreated, BF 10%, BF 20%, BF 30%, CuSO4 10%) and on vegetation period (Untreated, BF 75 g/ha, BF 112.5 g/ha, BF 225 g/ha, CuSO4 300g/ha) for 3 maize hybrids (Iezer, Felix, F 423). Also has been integrated in his crop technology cover crops and the using of organic agriculture inputs. The application of the product and agroecological measures had positive effects regarding the protection against pest Tanymecus dilaticollis. The damage degree was 16-19% in the untreated maize, while for the treated maize it was between 6-11%, the lowest values were observed for BF 30% on Iezer hybrid. The biostimulator had positive effects on plant growth and therefore on yield. The treatments or the type of hybrids did not influenced the weeding degree. [ABSTRACT FROM AUTHOR]

• On-farm evaluation of physico-chemical and microbial pathways of SOC accrual. • Comparison of 21 conventional and conservation farming systems at various soil types. • Conservation farming systems moderate microbially-mediated ('in-vivo') SOC dynamics. • Management practices influence biochemical parameters intrinsic to accrual pathways. Increasing pressure on arable land related to climate change mitigation and adaptation within recent policy frameworks has generated widespread interest in the effect of sustainable agricultural management practices on soil organic carbon (SOC) storage. Current frameworks point to soil microorganisms and their functioning as the key drivers of SOC accrual. This study provides a comprehensive on-farm assessment of changes in SOC formation pathways (physico-chemical and microbial) and the underlying drivers comparing three soil use systems: conservation and conventional farming systems as well as permanently vegetated adjacent reference soils (i.e., field margins) without agricultural land-use. Overall, our results indicated substantial increases in extractable organic carbon (+22 %), microbial biomass carbon (+29 %) and necromass carbon stocks (+11 %) in soils of conservation farming systems as compared to conventional farming systems. Differences between all three soil use systems were strongly pronounced in the surface soil (0–5 cm) and declined in deeper soil layers. Structural equation modelling revealed a varying influence of SOC storage pathways among soil use systems, with microbial-mediated ('in-vivo') turnover and direct sorption being the most dominant pathways. Moreover, diversity of crop rotation and tillage intensity were identified as the most important factors influencing extractable organic carbon and carbon-liberating enzyme activity within conservation farming management. Our on-farm approach demonstrates that enhanced bioavailable carbon inputs and reduced soil disturbance are the key drivers for microbially-controlled SOC accrual in arable soils and that conservation farming systems with extended plant coverage and increased crop diversity can substantially advance the restoration of soil health. [ABSTRACT FROM AUTHOR]

The objective of this experiment was to demonstrate the effectiveness of a commercially available tannin product (Silvafeed® ByPro, 70% tannic acid) as an enteric methane (CH4) mitigation and preventative animal health strategy in Holstein heifers (BW = 219 ± 17 kg; 9 mo), reared under organic production system requirements. Twenty heifers were randomly assigned to one of four commercial tannin supplementation treatments as follows: 0% (0 g/hd/d; CON), 0.075% (~5 g/hd/d; LOW), 0.15% (~10 g/hd/d; MED), and 0.30% (~21 g/hd/d; HIG) of dry matter intake (DMI). Heifers received their treatment in individual animal feeding stanchions and were fed a basal total mixed ration (TMR) through four SmartFeed Pro intake measurement bunk systems (C-Lock Inc., Rapid City, SD, USA) for 45 d. An automatic head chamber system (AHCS; i.e., GreenFeed, C-Lock Inc., Rapid City, SD, USA) was used to continuously evaluate enteric CH4 production. No effect was observed among the treatments for CH4 emissions (p ≥ 0.55), animal performance (p ≥ 0.38), or oxidative stress biomarker concentration (p ≥ 0.55). Superoxide dismutase (SOD) and reduced glutathione (GSH) concentrations exhibited a linear response to increasing tannin dose (p = 0.003), indicating a potential tannin effect on the antioxidant status of dairy heifers. This observation may encourage future tannin research relating to animal health, which may be of particular interest to organic dairy systems. The results of this study suggest that tannin supplementation at 0%, 0.075%, 0.15%, and 0.30% of DMI, did not alter CH4 emissions, animal performance, or oxidative stress biomarker concentration in organic Holstein heifers when assessed under an on-farm research approach. Further, the results of this study affirm the challenges associated with on-farm research and the development of climate-smart strategies that are capable of mitigating climate impacts in less controlled environments under standard working conditions.

Background: Goat production has grown worldwide as a way to improve the quality of rural life and reduce the environmental footprint; nevertheless, there is a need to increase productivity through improved feeding strategies. The market demands healthier products with organoleptic characteristics similar to the traditional ones; thus, it is necessary to evaluate the effect of new forages for goats and its acceptance by consumers. Chemical and organoleptic composition of goat milk vary according to the diet which, in turn, affects the characteristics of cheese. Cheese texture, taste and smell are the most important sensory attributes for consumers. Objective: To evaluate the effect of substituting corn straw with sunflower hay associated with chickpea for dairy goats on yield, chemical composition and sensory acceptability of cheese, as well profitability. Methods: Twenty-eight Saanen dairy goats were randomly assigned to two treatments in a 30-day experiment on a small farm. The daily ration per goat in the MZST treatment (control treatment) consisted of alfalfa hay (200 g/goat/day) and concentrate (400 g/goat/day) plus 600 g/goat/day (50% of the ration) of corn straw. The SFCP treatment substituted corn straw with sunflower-chickpea hay; it had the same alfalfa and concentrate content, but with no corn straw and was added with 600 g/goat/day of sunflower-chickpea hay. The yield, composition and sensory evaluation of fresh cheese made with milk from each treatment were recorded, and the feeding costs and returns evaluated. Variables for the chemical composition of cheese were analyzed following a completely randomized design. Results: Significant differences were observed in cheese yield and all chemical composition variables. According to sensory evaluation, SFCP cheese had significantly higher scores for texture and odor but lower for taste and overall acceptability compared to MZST. In terms of profitability, SFCP increased feed costs by 5% but resulted in higher margins over feed costs of 12 and 24% for milk and cheese, respectively, compared to MZST. Conclusion: In spite of favorable performance and economic returns of MZST treatment (control treatment), the organoleptic characteristics of the cheese reduced its general acceptance.

The convergence among the rise of digital technologies, the attention paid to the localized issues of transitions in practices toward agroecology, and the emergence of new open innovation models are renewing and reviving the scientific community's interest in on-farm experimentation (OFE). This form of experimentation is claimed to be enhanced by digital tools as well as being an enabler of production of credible, salient, and legitimate science insofar as it embraces a farmer-centric perspective. However, the forms of research in which some experimental activities on farms are anchored vary greatly, notably with regard to the actual forms that interventions on farms take, the legitimacy of the actors involved and their roles, or the observations and instruments applied for interpretation. We propose a systematic review of the literature and an analytical framework in order to better understand this diversity of practices behind on-farm experimentation. Our analysis segregated six major publication clusters based on themes appearing in titles and abstracts. These themes guided a more in-depth analysis of representative articles, from which we identified seven types of OFE practices that are described and discussed here with regard to the knowledge targeted, roles of the various actors, and on-farm experimental space. Our typology provides an original basis for supporting reflexivity and building alignment between the above-mentioned dimensions and the ways in which new tools can support the experimental process. [ABSTRACT FROM AUTHOR]

Integrated crop-livestock system (ICLS) is a useful practice to enhance soil organic carbon (SOC) compared to continuous cropping systems (CC). However, robust data from different regions around the world remain to be collected. So, our objectives were to (i) compare SOC and its physical fractions in ICLS and CC, and (ii) evaluate the use of δ13C to identify the source of C of SOC in these systems in the Pampas region of Argentina. For that, we compared two farms, an ICLS and a CC having the same soil type and landscape position. The ICLS farm produces alfalfa grazed alternatively with soybean and corn, and the CC farm produces the latter two crops in a continuous sequence. Soil samples (0–5, 5–20, 20–40, and 40–60 cm) were collected and analyzed for SOC, its physical fractions, and their isotopic signature (δ13C). Soils under ICLS showed an increment of 50% of SOC stock compared to CC in the first 60 cm. This increase was related to 100–2000 µm fractions of SOC. The shift in δ13C signature is more in ICLS than in CC, suggesting that rotation with C3 legumes contributed to C sequestration and, therefore, climate-smart agriculture. The combination of on-farm research and isotopic technique can help to study deeply the effect of real farm practices on soil carbon derived from pasture. [ABSTRACT FROM AUTHOR]

Adaptivity of eating and rumination behavior are assumed to play a particular role for cows in low-input systems, because they are more frequently challenged by altering forage quality. The present study examined relations between forage quality, chewing behavior and efficiency estimates in dairy cows from Swiss zero-concentrate organic farming systems. A total of 102 Swiss Fleckvieh cows on two organic dairy farms were observed during one full production year. Each farm was visited eight times. At each visit, up to 45 cows were equipped with RumiWatch® (Itin and Hoch GmbH, Liestal, Switzerland) sensor head collars, from which eating and rumination time and the frequency of activity changes were obtained for 48 h. Milk from one complete day was analyzed individually. All offered roughages (pasture herbage, grass silages and hay) were sampled at each visit and analyzed for crude fiber, crude protein and net energy, and a feed quality score was calculated. Metabolic production efficiency was estimated based on entire lactation data, and feed efficiency was estimated based on the individual farm visits. Lactation stage and forage quality significantly affected the chewing sensor variables. Eating time increased and rumination time decreased with the improved nutritive quality of feed. Coefficients of variance of the factor animal in the sensor variables showed a contribution of the individual cow to chewing behavior. Significant correlations between chewing sensor variables and efficiency estimates were not found. In conclusion, chewing behavior under on-farm conditions in low-input dairy farms alters during lactation and during changing forage quality, with significant animal effects, indicating potential for new phenotypes, albeit with no indications for efficiency. [ABSTRACT FROM AUTHOR]

Soil acidification is a major problem in the inland Pacific Northwest. A potential solution is the application of lime to neutralize acidity and raise pH. As lime is an expensive input, precision variable rate application is necessary. However, high-resolution mapping of pH and buffer pH for lime prescription requires costly sampling and analysis. To reduce the amount of sampling needed, remote sensing, which correlates with soil pH and buffer pH, can be used to determine optimal sampling locations and allow optimal interpolation. We used soil and crop data from the Washington State University R.J. Cook Agronomy Farm to develop an optimal sampling plan for a farmer’s property, followed that sampling design, and used the measured pH and buffer pH to fit a Bayesian hierarchical model using remote sensing variables specific to that farmer’s land. Following this, a new model was developed for the research farm with similar covariates. Ultimately, on the farmer’s field, we observed a root mean square error (RMSE) of 0.2487 for soil pH at a depth of 0–10 cm and 0.1221 for modified Mehlich buffer at 0–10 cm of depth. For the research farm, where buffer pH was not measured, we saw an RMSE of 0.3272 for soil pH at 0–10 cm of depth and 0.3381 for soil pH at 10–20 cm of depth. The ability make predictions of soil acidity with uncertainty using this technique allows for prescription lime application while optimizing soil sampling and testing. Further, this paper serves as a case study of on-farm research.

Conservation agriculture (CA) relies on low soil disturbance, mulching, and crop rotation, and these characteristics present CA as a good candidate to control soil degradation and preserve soil fertility. Therefore, agricultural scientists promote it as an efficient technique to sustain agricultural production. Conventional tillage (CT) dominates many semi-arid regions of Morocco, like Chaouia. However, crop/livestock management worsens degradation of soil organic matter and thus soil fertility. Since the eighties’, controlled experimental trials tried to promote No-Till (NT) system in these regions. But it is still experiencing a low level of adoption. This on-farm research study aimed to evaluate NT effect on some Vertisols' physicochemical properties of this region. Analysis of variance only found a significant NT effect on soil organic matter (SOM), but factorial analysis provided evidence of a behavior of its effect on several physicochemical properties such as active limestone (CaCO3), total nitrogen (TN), nitrate (NO3-), calcium (Ca2+), potassium (K+) and cation exchange capacity (CEC). Furthermore, pH, Electrical Conductivity (EC) and sodium (Na+) did not show any significant difference between the two tillage treatments. This study also found that continuous cereal cropping with no mulching management mostly explains this low improvement in soil quality. This last approach, reduce CA to NT process. To promote CA in these regions, more efforts are still needed for a satisfactory up-scaling and a sustainable soil fertility conservation.

The aim of this study was to investigate the impact of reduced stocking density in combination with provision of additional enrichment material on pig welfare on-farm. On three growing-finishing farms in Austria, in total 974, 413, and 70 pigs were kept at 1 m2/pig and straw or hay in a rack as additional enrichment material (improved pens, IP; n = 6–38 pens per farm) or in pens complying with the minimum legal requirements of 0.7 m2/pig (control pens, CP; n = 6–37 pens per farm). Behavior as well as skin, tail and ear lesions and pig soiling were assessed at the beginning and in the middle of the fattening period, while performance data were recorded at the end of the fattening period. Data analysis was performed for each farm separately using generalized linear and linear mixed models or Mann-Whitney U-Test. Pigs in IP less frequently manipulated pen mates' ears (Farm 1: Ptreatment*assessment = 0.002; Farm 2: P = 0.002) and body (Farm 1: P = 0.021; Farm 2: P = 0.015) than in CP. Prevalence of skin, tail and ear lesions and soiled pigs did not differ between treatments. In only one farm, average daily weight gain was higher in IP than in CP (Farm 1: P = 0.003). Our findings indicate that increased space allowance and provision of substrate can improve aspects of animal welfare within existing pig fattening systems, without requiring irreversible constructional modifications to the system.

Integrated crop-livestock system (ICLS) is a useful practice to enhance soil organic carbon (SOC) compared to continuous cropping systems (CC). However, robust data from different regions around the world remain to be collected. So, our objectives were to (i) compare SOC and its physical fractions in ICLS and CC, and (ii) evaluate the use of δ13C to identify the source of C of SOC in these systems in the Pampas region of Argentina. For that, we compared two farms, an ICLS and a CC having the same soil type and landscape position. The ICLS farm produces alfalfa grazed alternatively with soybean and corn, and the CC farm produces the latter two crops in a continuous sequence. Soil samples (0–5, 5–20, 20–40, and 40–60 cm) were collected and analyzed for SOC, its physical fractions, and their isotopic signature (δ13C). Soils under ICLS showed an increment of 50% of SOC stock compared to CC in the first 60 cm. This increase was related to 100–2000 µm fractions of SOC. The shift in δ13C signature is more in ICLS than in CC, suggesting that rotation with C3 legumes contributed to C sequestration and, therefore, climate-smart agriculture. The combination of on-farm research and isotopic technique can help to study deeply the effect of real farm practices on soil carbon derived from pasture.

Rice technologies that are designed to reduce risks due to climate variations, improve productivity, or overcome labor scarcity are important in tropical Asia. The objective of this study was to evaluate mechanized options for dry direct-seeding of rice in terms of the productivity and production costs in rainfed lowlands. In a series of on-farm research trials over 3 years in Ubon Ratchathani province, Thailand, we compared seeding by seed drills mounted on two-wheel tractors with manual broadcast seeding. Demonstration trials of seed drills and site-specific nutrient management in 2017 with 11 of 26 participating farmers produced 2.50 t ha−1 of grain yield, but unexpected heavy storms forced the other 15 farmers to switch from dry to wet direct-seeding or manual transplanting. The seed drills produced 32% higher grain yield than manual broadcast seeding (3.3 vs. 2.5 t ha−1) in 2014, and 14–24% higher yield (3.3–3.6 vs. 2.9 t ha−1) in 2015. Mechanized seeding enabled seeding rate reduction by 50% in 2014 and by 52–61% in 2015, resulting in lower production costs than with manual seeding. Our results suggest that mechanized dry direct-seeding of rice with improved nutrient management can enhance farmer livelihoods in rainfed environments in northeastern Thailand. This approach can significantly reduce production costs compared with manual transplanting, while maintaining or increasing productivity compared with conventional manual broadcast seeding. Abbreviations: THB: Thai Baht

Adaptivity of eating and rumination behavior are assumed to play a particular role for cows in low-input systems, because they are more frequently challenged by altering forage quality. The present study examined relations between forage quality, chewing behavior and efficiency estimates in dairy cows from Swiss zero-concentrate organic farming systems. A total of 102 Swiss Fleckvieh cows on two organic dairy farms were observed during one full production year. Each farm was visited eight times. At each visit, up to 45 cows were equipped with RumiWatch® (Itin and Hoch GmbH, Liestal, Switzerland) sensor head collars, from which eating and rumination time and the frequency of activity changes were obtained for 48 h. Milk from one complete day was analyzed individually. All offered roughages (pasture herbage, grass silages and hay) were sampled at each visit and analyzed for crude fiber, crude protein and net energy, and a feed quality score was calculated. Metabolic production efficiency was estimated based on entire lactation data, and feed efficiency was estimated based on the individual farm visits. Lactation stage and forage quality significantly affected the chewing sensor variables. Eating time increased and rumination time decreased with the improved nutritive quality of feed. Coefficients of variance of the factor animal in the sensor variables showed a contribution of the individual cow to chewing behavior. Significant correlations between chewing sensor variables and efficiency estimates were not found. In conclusion, chewing behavior under on-farm conditions in low-input dairy farms alters during lactation and during changing forage quality, with significant animal effects, indicating potential for new phenotypes, albeit with no indications for efficiency.

Planning and preparation can increase chances of successful outcomes from demonstration plots. This 5-page publication focuses on guiding the successful establishment of demonstration trials and is targeted to county, regional, and state specialized Extension faculty who aim to develop on-farm research and demonstration sites as part of their programs. Written by Marcelo Wallau, Esteban Rios, and Ann Blount, and published by the UF/IFAS Agronomy Department, January 2021.

The chief subject of this brief overview is a vetch species, once distinguished as Vicia calcarata Desf. and currently regarded as V. monantha Retz. subsp. triflora (Ten.) B. L. Burtt & P. Lewis, but we prefer to distinguish this taxon at species level as Vicia calcarata. It is a volunteer plant occurring regularly on ruderal sites in the local floras of the coastal and maritime areas of the Mediterranean Basin, and sporadically happens to be cultivated in fields. It has a more robust growth habit than V. monantha subsp. monantha, with usually three flowers per peduncle and larger seeds, rather constant morphological traits. In situ and on-farm observations on V. calcarata are scarce, relating mostly to the southern mainland of Italy and its islands, Spain, North Africa and Syria, where it is found in forests, grasslands, wheat fields, ruderal soils and along roadsides. On a global scale, there are 91 accessions of V. calcarata in six ex situ genebank collections in Alcalá de Henares, Bari, Beirut, Gatersleben, Sadovo and St. Petersburg. In a series of ex situ field trials in Novi Sad, twelve accessions of V. calcarata produced average yields of 6.3 t ha−1 of forage dry matter and 1100 kg ha−1 of seed. There are promising perspectives for developing cultivars of V. calcarata, since the available divergence offers a solid basis for crop improvement. After a long fall, a novel rise of V. calcarata is yet to come. [ABSTRACT FROM AUTHOR]

Successful organic farming requires crop varieties that are resilient to environmental variability. Assessing variety performance across the range of conditions represented on working farms is vital to developing such varieties; however, data collected from on-farm, participatory trials can be difficult to both collect and interpret. To assess the utility of data arising from participatory trialing efforts, we examined the performance of butternut squash (Cucurbita moschata L.), broccoli (Brassica oleracea L.) and carrot (Daucus carota L.) varieties grown in diverse organic production environments in participatory trials in Oregon, Washington, Wisconsin and New York using adaptability analysis (regression of variety means on environmental index). Patterns of adaptation varied across varieties, with some demonstrating broad adaptation and others showing specific adaptation to low- or high-yielding environments. Selection of varieties with broad vs specific adaptation should be guided by farmers' risk tolerance and on-farm environmental variation. Adaptability analysis was appropriate for continuous variables (e.g., yield traits), but less so for ordinal variables and quality traits such as flavor and appearance, which can be vitally important in organic vegetable crop variety selection. The relative advantages of adaptability analysis and additive main effects and multiplicative interactions are also discussed in relation to on-farm trial networks. This work demonstrated the unique challenges presented by extensive participatory vegetable trialing efforts, which, as compared to grain crops, require novel approaches to facilitating farmer participation as well as data collection and analysis. Efficient, precise and reliable methods for evaluating quality related traits in these crops would allow researchers to assess stability and adaptation across a wider range of traits, providing advantages for effective plant breeding and trialing activities within the organic sector. [ABSTRACT FROM AUTHOR]

Canola is one of the most important cash crops in Canada, but yields can be reduced by several insect pests including Lygus spp. (Hemiptera: Miridae). Canola cultivars have been improved substantially since economic thresholds were developed for Lygus in the 1990's. Thus, the objective of this study was to integrate a large data set collected over 23 years (1999–2021) from plots and commercial fields to update economic thresholds. Regression analysis of the data from the studied years from across distinct ecoregions yielded an overall Economic Injury Level (=action threshold) around 9–23 Lygus per 10 sweeps using the current (high) canola prices. However, insecticide trials at farmer's commercial fields, showed that yield was protected from Lygus feeding by spraying a foliar insecticide at the early pod stage only when catches exceeded 30 Lygus per 10 sweeps. Further analysis of Precision Yield Data (PYD) from combine yield monitors from southern Alberta, revealed that at low abundances, under 17 Lygus per 10 sweeps, Lygus may potentially stimulate canola yield and do not require a control action, unless there are more than 30 Lygus per 10 sweeps. Developing a long term data repository for PYD across multiple sites and spatial scales in the Prairies of Canada would allow future generations of researchers to improve decision making tools such as pest action thresholds, to develop a more resilient and sustainable agriculture. [Display omitted] • From 1999 to 2021 we collected data on canola yield and Lygus bug abundance in southern Alberta from 97 farm or plot sites to validate economic injury levels (EIL). • Linear or non-linear regression models suggested an EIL similar to the historical threshold around 15 Lygus per 10 sweeps. • A detailed analysis of Lygus abundance categories from Precision Yield Data showed that Lygus reduce yield only when they surpass 30 per 10 sweeps and plants can compensate or overcompensate for Lygus feeding below this abundance. • Economic Injury Levels based on overall regression analysis (linear or not) may ignore herbivore-plant interactions that occur at distinct regions of arthropod densities. • Ideally, EIL's should be validated on farms and with large historical data sets. [ABSTRACT FROM AUTHOR]

Rice technologies that are designed to reduce risks due to climate variations, improve productivity, or overcome labor scarcity are important in tropical Asia. The objective of this study was to evaluate mechanized options for dry direct-seeding of rice in terms of the productivity and production costs in rainfed lowlands. In a series of on-farm research trials over 3 years in Ubon Ratchathani province, Thailand, we compared seeding by seed drills mounted on two-wheel tractors with manual broadcast seeding. Demonstration trials of seed drills and site-specific nutrient management in 2017 with 11 of 26 participating farmers produced 2.50 t ha−1 of grain yield, but unexpected heavy storms forced the other 15 farmers to switch from dry to wet direct-seeding or manual transplanting. The seed drills produced 32% higher grain yield than manual broadcast seeding (3.3 vs. 2.5 t ha−1) in 2014, and 14-24% higher yield (3.3-3.6 vs. 2.9 t ha−1) in 2015. Mechanized seeding enabled seeding rate reduction by 50% in 2014 and by 52-61% in 2015, resulting in lower production costs than with manual seeding. Our results suggest that mechanized dry direct-seeding of rice with improved nutrient management can enhance farmer livelihoods in rainfed environments in northeastern Thailand. This approach can significantly reduce production costs compared with manual transplanting, while maintaining or increasing productivity compared with conventional manual broadcast seeding. Abbreviations: THB: Thai Baht [ABSTRACT FROM AUTHOR]

Site-specific nutrient management (SSNM) can be an alternative to a recommendation for uniform fertilizer use across a rice (Oryza sativa L.) production system within a country or region of a country. We developed a web-based decision support tool named Nutrient Manager for Rice (NMR), which used principles of SSNM to calculate fertilizer N, P, and K rates for individual fields based on a target yield set for each field. It also used expected growth duration of the rice variety, crop establishment method, and age of transplanted seedlings to calculate days after rice establishment for each of three applications of fertilizer N. NMR enabled P rates to match estimated removal of P with harvested grain and crop residue for the target yield set for each field. We compared field-specific fertilizer recommendations from NMR with uniform application of fertilizer provided by an existing blanket fertilizer recommendation for irrigated inbred rice (BFR) and farmer's fertilizer practices (FFP) in on-farm trials conducted in 74 irrigated rice fields across three growing seasons in the Cauvery Delta, Tamil Nadu, India. Grain yield was 0.6-0.7 Mg ha−1 higher (P ≤ 0.05) with NMR than FFP in two of the three seasons, even though total fertilizer cost was comparable or less with NMR. Yield was comparable for NMR and BFR, but NMR reduced fertilizer N and P rates and total fertilizer cost compared to BFR. Use of NMR rather than BFR also had less risk of financial loss for a farmer. The likelihood of financial loss with a switch from FFP to BFR averaged 31%. It reduced to 18% with a switch from FFP to NMR. NMR facilitated the calculation of field-specific fertilizer N, P, and K management practices, which increased fertilizer use efficiency without loss in rice yield compared to a recommended uniform fertilizer management across fields. [ABSTRACT FROM AUTHOR]

Performance of hybrid red tilapia (Mutant, Oreochromis niloticus × Oreochromis mossambicus) and GIFT tilapia strain (Oreochromis niloticus) in C/N-CP prawn (Macrobrachium rosenbergii) farming system was evaluated at the farmers' pond at Bailor union under Trishal upazilla of Mymensingh district, Bangladesh. The on-farm trial had two treatments: TR and TG (named according to the tilapia strains) with three replications. Six rectangular ponds of varying sizes (400–880 m2) were used for this experiment. Hybrid red and GIFT tilapia stains were stocked with prawn at the stocking densities of 1 tilapia fingerlings (either red or GIFT strain) and 3 prawn juveniles m-2 in both treatments. Bamboo side shoot were posted vertically as periphyton substrate. This resulted in an additional substrate surface area of 1067 m2 for periphyton development equaling 147% of the pond surface area. Considering the body weight of freshwater prawn only, feeding rates were 10% of body weight at the beginning of the study (up to 30 days), and feeding application was gradually reduced to 3% in the last month assuming 80% survival. The abundance of total benthos and periphyton as well as total periphytic biomass were significantly higher (P

An effective adaptive strategy for reducing climate change risks and increasing agro-system resiliency is broadening cropping system diversity, heightening the flexibility of cultivation and tillage methods. Climate change impacts on standard cultivation practices such as mineralisation and nitrate leaching due to mild and rainy winters, as well as frequent drought or water saturation, not only limiting fieldwork days, but also restricting ploughing. This calls for alternative methods to counteract these propensities. From 2010 to 2013, a farming system experiment was conducted on a distinctly heterogeneous organic farm in Brandenburg, Germany. With the intention of devising a more varied and flexible winter wheat cultivation method, standard organic farming practices (winter wheat cultivation after two years of alfalfa-clover-grass and ploughing in mid-October) were compared to four alternative test methods, which were then evaluated for their robustness and suitability as adaptive strategies. Two of the alternative methods, early sowing and catch crop, entailed moving up the date for alfalfa-clover-grass tilling to July. Instead of a plough, a ring-cutter was used to shallowly (8 cm) cut through and mix the topsoil. In the early sowing test method, winter wheat was sown at the end of August, after repeated ring-cutter processing. With the catch crop method, winter wheat seeding followed a summer catch crop and October tillage. The two oat methods (oat/plough; oat/ring-cutter) entailed sowing winter wheat in September, following oat cultivation. Overall, the cultivation methods demonstrated the following robustness gradation: standard practice = catch crop ≥ early sowing > oat/plough > oat/ring-cutter. When compared to standard procedures, the catch crop and early sowing test methods showed no remarkable difference in grain yields. Measured against early sowing, the catch crop test method was significantly more robust when it came to winterkill, quality loss, and weed infestation (40% lower weed-cover). High Nmin- values (up to 116 kg N ha-1) in autumn could have caused the chamomile and thistle infestation in both oat/ploughoat/ring-cutter test methods, which led to crop failure in the hollows. Compared to standard practices, the oat ring-cutter test method brought in over 50% less grain yield. This was attributed to ring-cutter processing, which reduced N mineralisation and caused high weed infestation. However, the ring-cutter effectively regulated alfalfa-clover-grass fields in both exceedingly wet and very dry weather; a temporal flexibility which increases the number of fieldwork days. The catch crop and early sowing test methods contributed most to boosting future agronomic diversity.

Maize production in western Kenya is often limited by deficiencies of nitrogen and phosphorus. We assessed the effectiveness of Tithonia diversifolia green manure (tithonia), farmyard manure (FYM) and urea as sources of nitrogen (N) for maize when inorganic phosphorus (P) fertiliser was either broadcast (BR) or spot-placed in the planting hole (SP) for two consecutive seasons; October to December of 1998 and April to August of 1999 at two sites; Nyabeda and Khwisero in western Kenya. A randomised complete block design with four replications was used. Maize yields were higher at Nyabeda and responded to P application better than at Khwisero. At the same N rate, tithonia and FYM were as effective as urea in increasing maize yields at both sites. There were no significant differences in maize yields when phosphate fertiliser was either BR or SP regardless of the N source used in the first season. However, in the second season, the residual yields for the BR treatments were consistently higher than those of the SP. Our results suggest that tithonia and FYM can substitute for urea as N sources and that fertiliser P should be broadcast and incorporated together with the organic materials at the time of planting to save on labour costs.

The objective of this experiment was to demonstrate the effectiveness of a commercially available tannin product (Silvafeed ® ByPro, 70% tannic acid) as an enteric methane (CH 4 ) mitigation and preventative animal health strategy in Holstein heifers (BW = 219 ± 17 kg; 9 mo), reared under organic production system requirements. Twenty heifers were randomly assigned to one of four commercial tannin supplementation treatments as follows: 0% (0 g/hd/d; CON), 0.075% (~5 g/hd/d; LOW), 0.15% (~10 g/hd/d; MED), and 0.30% (~21 g/hd/d; HIG) of dry matter intake (DMI). Heifers received their treatment in individual animal feeding stanchions and were fed a basal total mixed ration (TMR) through four SmartFeed Pro intake measurement bunk systems (C-Lock Inc., Rapid City, SD, USA) for 45 d. An automatic head chamber system (AHCS; i.e., GreenFeed, C-Lock Inc., Rapid City, SD, USA) was used to continuously evaluate enteric CH 4 production. No effect was observed among the treatments for CH 4 emissions ( p ≥ 0.55), animal performance ( p ≥ 0.38), or oxidative stress biomarker concentration ( p ≥ 0.55). Superoxide dismutase (SOD) and reduced glutathione (GSH) concentrations exhibited a linear response to increasing tannin dose ( p = 0.003), indicating a potential tannin effect on the antioxidant status of dairy heifers. This observation may encourage future tannin research relating to animal health, which may be of particular interest to organic dairy systems. The results of this study suggest that tannin supplementation at 0%, 0.075%, 0.15%, and 0.30% of DMI, did not alter CH 4 emissions, animal performance, or oxidative stress biomarker concentration in organic Holstein heifers when assessed under an on-farm research approach. Further, the results of this study affirm the challenges associated with on-farm research and the development of climate-smart strategies that are capable of mitigating climate impacts in less controlled environments under standard working conditions.

Highlights • Actionable knowledge on a little-known crop was produced using participatory design. • A multi-actor workshop and on-farm trials were combined to enhance innovative design. • Farmers introduced camelina as summer second crop in their cropping systems. • Assessment and monitoring indicators for camelina were identified. • Knowledge gaps hampering the development of camelina in fields were identified. Abstract New cropping systems are needed to meet the increasing demand for sustainable feedstock for food, feed, fibre, and fuel. However, the lack of agronomic knowledge has been shown to hinder the introduction of new crops in current cropping systems. In design sciences, the C–K theory, which was developed to model design logics, shows that a design process could be a relevant tool to produce knowledge. In this study, an original participatory design approach combining a multi-actor workshop and on-farm trials was developed to produce actionable knowledge and identify knowledge gaps. The work was based on a case study: the introduction, in the cropping systems of northern France, of a little-known oilseed crop, camelina [ Camelina sativa (L.) Crantz], to supply a local oilseed biorefinery. During the workshop, farmers, researchers, and industrialists collectively designed eight crop sequences that included camelina as a second crop, and two crop management options, as a relay crop and a double crop. These design activities allowed for the identification of: (i) assessment indicators derived from participants' expectations; and (ii) knowledge gaps about camelina crop functioning, management, and preceding crop effects. After the workshop, four farmers implemented on-farm trials. They autonomously designed and managed thirteen crop management options, and appraised them according to their own indicators. These on-farm trials were monitored through interviews, field tours, and measurements. Eleven criteria used by the farmers to appraise their trials were identified. Four crop management options were considered as conclusive, three as not conclusive, and six as promising. The monitoring of these original on-farm trials allowed for: (i) the identification of farmers' monitoring indicators; (ii) the formulation of decision rules for camelina management; (iii) a better understanding of camelina crop functioning; and (iv) the identification of farmers' questions, revealing knowledge gaps to be fulfilled to enhance camelina areas. In this study, we demonstrated that participatory design could be used to: (i) support, at a low cost, the production of actionable knowledge on a little-known crop; and (ii) pursue the identification of relevant topics lines for research-action programs. We also showed that the combination of a multi-actor workshop and new kinds of on-farm trials is relevant to reach these objectives. In conclusion, this approach could be an interesting way to support the design of diversified cropping systems, including little-known crops such as camelina, and to help in the setting of research priorities for these crops. [ABSTRACT FROM AUTHOR]

Nutrient management can increase crop yield and income, but its effects on yield components are rarely dissected in on-farm research. In this study, we compared aboveground biomass and yield components of rainfed lowland rice under site-specific nutrient management and farmer management from 69 demonstration sites prone to mild to moderate intermittent drought across 9 Philippine provinces over 3 years (the 2011–2013 wet seasons). The sink size (spikelets m −2 ) was most closely associated with grain yield in all years. Panicle size (spikelets per panicle) increased by 10.4% and 13.0% in 2011 and 2012, respectively, under site-specific nutrient management, with N application around the early reproductive stage of <25 kg N ha −1 in farmer nutrient management versus 30–33 kg N ha −1 in site-specific management. Higher N application during seedling establishment in farmer nutrient management (55 kg N ha −1 ) than in site-specific management (22 kg N ha −1 ) did not increase panicles m −2 in any year. Our results demonstrate the yield advantage of site-specific nutrient management in rainfed lowland rice in relatively fertile and less drought-prone environments: enhancing sink size should be the major target of nutrient management; it is unnecessary to apply high amounts of N during seedling establishment to secure a sufficient panicle number; and N application is most important during the early reproductive stage to increase panicle size. [ABSTRACT FROM AUTHOR]

Cover crop mixtures with complementary plant functional traits including biological nitrogen fixation (BNF) may supply nitrogen (N) to farm fields while simultaneously providing other ecosystem functions such as N retention and weed suppression (i.e., multifunctionality). Understanding variation in these relationships across farms can help advance trait-based research in agroecology and ecological approaches to nutrient management., This on-farm experiment explored the contributions of two- and three-species cover crop mixtures, which combined legumes, brassicas and cool season grasses, to ecosystem functions across a gradient of soil fertility levels driven by farm management history., I evaluated the predictions that functional trait diversity of the cover crops would explain variation in multifunctionality, and that legume biomass and BNF within mixtures would be inversely correlated with indicators of soil N availability from organic matter across the farm gradient., Ecosystem functions varied widely across farms. As expected, functional diversity was a significant predictor of multifunctionality, although the relationship was weak. Cover crop mixtures had significantly greater multifunctionality than a cereal rye monoculture, though not at the highest observed levels of each function, indicating trade-offs among functions. Linear regression models showed that legume biomass and BNF were negatively correlated with soil properties indicative of N availability from soil organic matter, whereas non-legume and weed biomass were positively correlated with other measures of soil fertility., Synthesis and applications. Cover crop mixtures can increase functional diversity within crop rotations. Designing mixtures with complementary plant traits may be particularly effective for increasing multifunctionality and agroecosystem sustainability. On-farm research to understand variation in biological nitrogen fixation, which is both a plant trait and a key ecosystem function, across heterogeneous soil conditions, can inform management of soil fertility based on ecological principles. [ABSTRACT FROM AUTHOR]

Organic agriculture continues to expand in the USA and in the European Union (EU), particularly in Italy, which had 48,650 organic farms in 2014 compared with 19,474 in the USA. Additionally, EU support for organic research is nearly double than that of the USA. Along with increased support for organic research, the EU organic community has achieved recognition at the European Commission policy level for a dedicated innovation platform, advocating the practice of farmer-first models for participatory research. The US land-grant universities have a long history of on-farm research, primarily through the Extension Service, but the need exists for more inclusive, second-loop, co-research with organic farmers. A survey was conducted of organic farmers and researchers in Italy and in the USA to ascertain the extent of participatory organic research activities and experiences, and explore the vision each group had for the future of co-innovation between organic farmers and researchers. Results indicated that, despite the higher level of organic research support in the EU, the percentage of researchers involved in on-farm/participatory organic research was equivalent in Italy and the USA, presumably due to the more recent emphasis in Italian/EU agricultural research agendas on the importance of farmer knowledge and participation in organic research. Overall, 60% of surveyed organic researchers in both countries cited involvement in on-farm/participatory organic research, with ‘farming systems’ and ‘nutrient/pest management’ the main research focus in the USA, compared with ‘farming systems’ and ‘equipment’ in Italy. Both countries’ researchers expressed their vision of participatory research as helping to improve communication between researchers and farmers, to enable work on relevant research, and to allow farmers to adapt technologies to their own conditions. Organic farmers in Italy completed survey questionnaires as part of a field day activity, leading to more Italian farmers responding to the survey, compared with USA counterparts who were queried via e-mail. Organic farmers in Italy identified ‘knowledge-sharing’ as a critical value of participatory research, and were conducting on-farm research with less compensation than US farmers. The ‘lack of time’ was cited as the most important constraint limiting participatory research by Italian and US farmers, although the ‘lack of common language’ also was rated as potentially impairing full participation. Lessons shared between EU and US organic researchers as a result of this project included methods to institute policies aimed at increasing support for organic research and co-innovations with organic farming communities, and connecting experienced on-farm researchers in the US with Italian colleagues to enhance collaborative activities with organic farmers. [ABSTRACT FROM PUBLISHER]

Most non-genetically modified (GM) soybean ( Glycine max Merr.) cultivars are bred and performance-tested under conventional conditions and have rarely been tested in organic production. Twelve non-GM soybean cultivars were evaluated in weed-free and weedy conditions on 5 organic farms and 1 transitional farm in southern Manitoba in 2014 and 2015. The mean cultivar yield ranged from 1384 to 1807 kg ha −1 . Weed biomass at soybean maturity ranged from 1289 to 2553 kg ha −1 and was significantly affected by cultivar. Significant site–cultivar interactions were observed for soybean biomass, height, and yield. Site accounted for 72.4% of yield variability; cultivar accounted for only 1%. Our hypothesis that cultivars with greater early season height are more competitive with weeds was not supported. Yield loss due to weeds ranged between 20 and 44%; lower yield loss was associated with timely weed management. Partial least squares regression was used to assess the main factors controlling grain yield. Higher soil nitrate (N) status negatively impacted final grain yield in this study, suggesting that soil nutrient status impacted the soybean cultivars’ competitive ability against weeds. Results suggest that weed management and soil N status are of equal importance to cultivar choice for successful organic soybean production in Manitoba. [ABSTRACT FROM AUTHOR]

Simple tools for diagnosing crop nutritional status are in great demand by agricultural extension staff, particularly in low‐fertility environments. We developed the first practical method for in situ diagnosis of phosphorus (P) nutrition in field‐grown cereal crops by using a handheld colorimeter. The concentration of P in extracts from fresh leaves of lowland rice grown under various P availabilities was closely correlated with that of oven‐dried leaves measured with the standard molybdenum‐blue method in the laboratory, over a range of values from 0.319 to 1.420 mg P g −1 DW (r = 0.885**, n = 14). It takes only 3–5 min to estimate the P concentration of plant samples using the new technique. Although not as accurate as the laboratory method, the new method can easily detect P deficiency of rice in the field (and possibly other cereal crops) without requiring costly, off‐site equipment. Thus, extension staff and agronomists can easily adopt this technique. [ABSTRACT FROM AUTHOR]

In his interesting Viewpoint article in Water Alternatives, Bruce Lankford suggests that an African Green Revolution cannot come about without irrigation. But he does not convincingly explain why irrigated areas expand only very slowly. This viewpoint article argues that grain yields have remained stagnant in Africa because of high temporal rainfall variability, significant spatial soil nutrient heterogeneity, and weak and volatile markets. This combination calls for location-specific interventions that are aimed at enhancing farmers’ capacity to buffer water variations and address nutrient deficits. This finding is consistent with what Lankford dismisses as an "atomised" approach, but which would preferably be called a farmer-centred approach. Thus a massive investment in African agriculture is indeed required, primarily focused on the creation of knowledge that does justice to the local variation in water and nutrient availability. It should aim to empower farmers to experiment and be innovative, and remake agricultural extension and agricultural engineering exciting with cutting-edge disciplines. Irrigation may then emerge as the right thing to do.

In the present field study, the effects of applying biogas slurry for 25 years on soil microbiological and soil chemical properties were investigated in comparison with the application of raw cattle slurry. An on-farm research approach was used with pairwise comparison of neighboring fields, taking samples at a high spatial resolution from two biodynamic farms down to 10 cm. Texture, soil organic C (SOC), total N and P, microbial biomass C, N, and P as well as P fractions were determined by different extraction procedures. Application of biogas slurry had no significant effects on SOC, total N, or microbial biomass C, N, and P. Clay and pH effects outweighed site-specific differences for most properties. Biogas slurry increased the fractions of plant-available inorganic phosphate (+66 % more Olson-P) and of Ca-associated phosphates (+40 % 1 M HCl-P) at the expense of hardly soluble Fe and Al phosphates (-25 % 6 M HCl-P). This is in line with the observation that biogas slurry contains significantly more HO-P and 1 M HCl-P than raw slurry. The long-term application of biogas slurry had no negative impacts on any of the soil properties analyzed. [ABSTRACT FROM AUTHOR]

Adapting agricultural systems to the effects of climate change requires farm-specific innovations and adaptive measures. Such innovative measures were developed for organic farming systems in the federal state of Brandenburg, Germany by a regional innovation network using an action research approach. The goal of the presented approach was to address climate change-related farm-specific problems, develop specific adaptation measures and learn new approaches such as proactive risk management and strategic adaptive behaviour. In a cyclical process of analysis, planning, action and reflection, the network of researchers and organic farmers repeatedly used SWOT (strengths, weaknesses, opportunities and threats) analyses to structure the transdisciplinary innovation and adaption process. First, the organic farmers identified as main weaknesses the water and nitrogen supply likely to be worsened by climate change; then, farm-specific adaption measures were identified and tested by conducting on-farm experiments at six organic farms. By evaluating and thus adjusting and retesting the measures in consecutive trials, new farming methods were developed to increase diversification and decrease risk in organic farming practices. Along with the iterative process, the network was expanding and the collective learning process led to changes in attitudes and behaviour. A clear example is the stakeholders' initially positive view of reduced tillage, which they later questioned and changed. The participating organic farmers proved to be active partners; their openness to innovation and their approach to problem solving make them well suited to action research. In adapting regions to climate change, these kinds of stakeholders will play a decisive role. [ABSTRACT FROM AUTHOR]

Winter wheat ( Triticum aestivum L.) represents almost 50% of total cereal production in the European Union, accounting for approximately 25% of total mineral nitrogen (N) fertilizer applied to all crops. Currently, several active optical sensor (AOS) based systems for optimizing variable N fertilization are commercially available for a variety of crops, including wheat. To ensure successful adoption of these systems, definitive measurable benefits must be demonstrated. Nitrogen management strategies developed based on small-scale plot research are not always meaningful for large-scale farm conditions. In 2010–2012 (5 site-years) on-farm study was implemented in northern Poland utilizing a strip-trial design. The objective was to evaluate the performance of AOS in combination with a built-in algorithm for variable N rate fertilization. In this study, the reference uniform N rates (farmer’s practice) were comparable to optimum variable N rate recommendations. Side-by-side comparisons of uniform and variable N application revealed inconsistent benefits in terms of grain yield, grain protein content (GPC), N use and N use efficiency (NUE). Anticipated yield increases and/or reduced N rates are typical drivers for AOS adoption. Significant yield increases are not easily attained on farms with winter wheat yields already close to maximum yield potential. Thus, sensor-based variable N rate recommendations for fields previously fertilized with relatively low uniform N rates would often entail more appropriate allocation (redistribution) of the same amount of total N. This would minimize N surplus in areas of lower productivity and to improve the sustainability of N management overall. [ABSTRACT FROM AUTHOR]

Miscanthus × giganteus is often regarded as one of the most promising crops to produce bioenergy because it is renowned for its high biomass yields, combined with low input requirements. However, its productivity has been mainly studied in experimental conditions. Our study aimed at characterizing and explaining young M. giganteus yield variability on a farmers' field network located in the supply area of a cooperative society in east central France. It included the first three growth years of the crop. We defined and calculated a set of indicators of limiting factors that could be involved in yield variations and used the mixed-model method to identify those explaining most of the yield variation. Commercial yields averaged 8.1 and 12.8 t DM ha−1 for the second and third growth year, respectively. However, these mean results concealed a high variability, ranging from 3 to 19 t DM ha−1. Commercial yields, measured on whole fields, were on average 20% lower than plot yields, measured on a small area (two plots of 25 m2). Yields were found to be much more related to shoot density than to shoot mass, and particularly to the shoot density established at the end of the planting year. We highlighted that planting success was decisive and was built during the whole plantation year. Fields with the lowest yields also had the highest weed cover, which was influenced by the distance between the field and the farmhouse, the preceding crop and the soil type. Our findings show that growing young M. giganteus on farmers' fields involves limiting factors different from those commonly reported in the literature for experimental conditions and they could be useful to assess the economic and environmental impacts of growing M. giganteus on farmers' fields. They could also stimulate the discussion about growing bioenergy crops on marginal lands. [ABSTRACT FROM AUTHOR]