Performance Of Cropping Systems Research Articles

Wheat improves nitrogen use efficiency of maize and soybean-based cropping systems

Integrated nitrogen (N) management strategies could make significant contributions to improving the efficiency of N use in the northern Corn Belt, particularly for maize, which has high N requirements. Using legume cover crops has been shown to increase both the soil's capacity to supply N and nitrogen use efficiency (NUE), through the reduction in the amount of N fertilizer that must be applied to the following crops. However, the impact of non-legume crops such as winter wheat (Triticum aestivum L.) on the diminishing return function between crop yield and N supply and its influence on N fertilizer use remains unclear. We hypothesized that maintaining wheat in short maize and soybean- based rotations is instrumental to improve cropping system performance and increase N fertilizer use efficiency while decreasing N requirements for maize. Seven maize and soybean rotations with different frequency of winter wheat with or without underseeded red clover (Trifolium pratense L.) were grown in two tillage systems (conventional and zone-tillage) and four long-term N regimes in Ridgetown, ON, Canada (2009–2013). Wheat in the rotation increased maize and soybean yields, negated crop yield lags due to zone-tillage, and decreased maximum economic rates of fertilizer N (MERN). The benefits of wheat in the rotation on maize yield were negated by high N rates; however, similar yields were obtained with lower N levels in rotationally grown maize, resulting in a 17% (conventional till) to 21% (zone-till) increase in partial factor productivity for N fertilizer at MERN (PFPMERN). While N benefits to crops following wheat alone may be attributed to a higher indigenous plant available soil N, underseeding red clover further increased the agronomic efficiency (AE) of N fertilizer (AEMERN) up to 32%. Maize yields were also less limited by N supply and less responsive to N fertilization when grown in rotation with wheat, especially in the zone-till system. These results highlight the value of wheat as a system component of dominant maize/soybean short rotations of Ontario and its potential to increase both maize and soybean productivity using less N input.

Which cropping systems to reconcile weed-related biodiversity and crop production in arable crops? An approach with simulation-based indicators

Weed management must both control weed harmfulness for crop production and promote weed contribution to biodiversity as an essential component of biodiversity in agricultural landscapes. The objective of the present paper was to evaluate a large range of existing cropping systems to determine management rules for reconciling weed-related biodiversity and weed harmfulness, comparing 26 contrasting cropping systems identified via farm surveys in two contrasting French regions, Burgundy and Poitou-Charentes. These systems were simulated, using the weed dynamics model FlorSys which predicts weed flora dynamics over the years, depending on cropping system and pedoclimate. The simulated flora was translated into five weed harmfulness indicators (crop yield loss, harvest contamination, harvesting difficulty, field infestation, additional crop disease due to weeds) and five weed-related biodiversity indicators (weed species richness and equitability, weed-based trophic offer for birds, insects and pollinators). Cropping system performance was assessed with a Principal Component Analysis (PCA) on the 10 weed-impact indicators, followed by a hierarchical clustering analysis. Five contrasting profiles in terms of weed harmfulness and contribution to biodiversity were identified, combining different levels of weed harmfulness and biodiversity. To identify management strategies (i.e., combinations of cultural practices) for reaching these different performance profiles, tree-based regression and classification models (CART) were constructed to explain performance profiles as a function of cropping system descriptors and pedoclimatic variables. Ten management strategies were identified for reaching the five performance profiles. The most interesting performance profile, which minimized all harmfulness indicators (except harvest contamination and harvesting difficulty) and maximized all biodiversity indicators (except species richness), was reached by a single strategy type, consisting of low or no-till systems. Systems with cover crops and little or no mechanical weeding also reconciled most production and biodiversity goals. Multiple management pathways for reaching a given goal present the advantage of letting farmers choose the strategy most compatible with the objectives and constraints of their farm. The present results were obtained with annual weed species only, and taking into account the management of perennial weeds will probably modify the strategies. The same method was also applied to identify strategies for reconciling crop production, biodiversity and reduced herbicide use, though none of the investigated cropping systems was able to reconcile all three objectives, indicating that novel cropping systems must be designed specifically for this objective.

A vast range of opportunities for feeding the world in 2050: trade-off between diet, N contamination and international trade

Through a detailed analysis of the FAO database, we have constructed a generalized representation of the nitrogen transfers characterizing the current agro-food system (GRAFS) of 12 macro-regions of the world in terms of functional relationships between crop farming, livestock breeding and human nutrition. Based on this model, and maintaining the current cropland areas and the performance of cropping and livestock systems in each region, we have assessed the possibilities of meeting the protein requirements of the estimated world population in 2050, according to various combinations of three critical drivers namely human diet (total amount of protein consumed and share of animal protein in this total), regional livestock production and crop fertilization intensity, in each region. The results show that feeding the projected 2050 world population would generally imply higher levels of inter-regional trade and of environmental nitrogen contamination than the current levels, but that the scenarios with less recourse to inter-regional trade generally produce less N losses to the environment. If an equitable human diet (in terms of protein consumption) is to be established globally (the same in all regions of the world), the fraction of animal protein should not exceed 40% of a total ingestion of 4 kgN capita−1 yr−1, or 25% of a total consumption of 5 kgN capita−1 yr−1. Our results show that slightly improving the agronomical performance in the most deficient regions (namely Maghreb, the Middle East, sub-Saharan Africa, and India) would make it possible not only to meet the global protein requirements with much less international trade (hence more food sovereignty), but also to reduce N environmental contamination the most efficiently.

Permanent raised beds improved crop performance and water use on the North China Plain

Conservation Agriculture (CA) has been shown to improve cropping system performance around the world. However, there is limited research on this practice in the annual double cropping areas of the North China Plain and consequently limited uptake of the technology by the farming community. Data from a field experiment (2005 to 2011) conducted in Daxing, Beijing, China, were used to compare the effects of tillage practices, namely permanent raised beds (PRB), no-tillage (NT), and traditional tillage (TT) on growth, yield, and water use of winter wheat (<i>Triticum aestivum</i> L.) and summer maize (<i>Zea mays</i> L.). Results demonstrated that PRB increased soil water content (0 to 0.3 m [0 to 0.98 ft] depth; &gt;8%) and reduced bulk density by 5.1%. Permanent raised bed soil temperatures were stabilized during winter wheat and summer maize production, compared to NT and TT treatments. Over the six years, PRB yields increased by &gt;3% and gross production water use index (GPWUI) improved by &gt;2.5% compared to TT, due to improved soil properties and crop performance. However, the impact of the changed management practices was not realized until the final two seasons, when yields improved by &gt;6%. Accordingly, differences in farming profits, when viewed over the six years were intangible, but improved significantly by &gt;20% in the final two seasons. These improvements in soil properties, yield, and water use are of considerable importance for food security and sustainable agriculture in the North China Plain; however, limited understanding of the farming system and extended timeframes required before realizing beneficial returns continue to limit widespread adoption.

Agronomic and economic performances of different cropping systems in a hot, arid environment: A case study from North-western Rajasthan, India

A four-year field experiment was conducted in order to assess the productivity and economic potential of five cropping systems, with two tillage (conventional and deep) and four nutrient management [no application, farm yard manure (FYM) at 5 t ha−1, chemical fertilizer (CF), FYM at 5 t ha−1 + CF] treatments in a hot, arid environment at Bikaner, India. Pearl millet [Pennisetum glaucum (L.) R. Br], cluster bean [Cyamopsis tetragonoloba (L.) Taub.] and moth bean [Vigna aconitifolia (Jacq.) Marechal] were grown in five rotations. The five rotations were: moth bean–pearl millet, cluster bean–pearl millet, moth bean–cluster bean, pearl millet–pearl millet and pearl millet + cluster bean–pearl millet + cluster bean. The moth bean–cluster bean cropping system recorded 21–148%, 36–246% and 33–178% higher equivalent yields, return and water use efficiency, respectively than other cropping systems. Deep tillage increased equivalent yields by 20% higher than conventional tillage. The combined application of CF and FYM recorded 15 and 32% higher equivalent yields than their respective sole application. In this hot, arid ecosystem, a legume–legume system was more productive and profitable than other systems, and higher crop yields could be achieved by combining deep tillage with the integrated use of CF and FYM.

A calibration procedure to improve global rice yield simulations with EPIC

Crop models are increasingly used to assess impacts of climate change/variability and management practices on productivity and environmental performance of alternative cropping systems. Calibration is an important procedure to improve reliability of model simulations, especially for large area applications. However, global-scale crop model calibration has rarely been exercised due to limited data availability and expensive computing cost. Here we present a simple approach to calibrate Environmental Policy Integrated Climate (EPIC) model for a global implementation of rice. We identify four parameters (potential heat unit – PHU, planting density – PD, harvest index – HI, and biomass energy ratio – BER) and calibrate them regionally to capture the spatial pattern of reported rice yield in 2000. Model performance is assessed by comparing simulated outputs with independent FAO national data. The comparison demonstrates that the global calibration scheme performs satisfactorily in reproducing the spatial pattern of rice yield, particularly in main rice production areas. Spatial agreement increases substantially when more parameters are selected and calibrated, but with varying efficiencies. Among the parameters, PHU and HI exhibit the highest efficiencies in increasing the spatial agreement. Simulations with different calibration strategies generate a pronounced discrepancy of 5–35% in mean yields across latitude bands, and a small to moderate difference in estimated yield variability and yield changing trend for the period of 1981–2000. Present calibration has little effects in improving simulated yield variability and trends at both regional and global levels, suggesting further works are needed to reproduce temporal variability of reported yields. This study highlights the importance of crop models’ calibration, and presents the possibility of a transparent and consistent up scaling approach for global crop simulations given current availability of global databases of weather, soil, crop calendar, fertilizer and irrigation management information, and reported yield.

Assessment of regional variability in crop yields with spatial autocorrelation: Banana farms and policy implications in Martinique

Agricultural research can support farmers and policy makers’ decisions by identifying the causes of spatial variability in crop yield at a regional level. In this paper, we propose a method that combines spatial autocorrelation measures and a farm network survey. This method is intended to describe the causes of spatial variability in crop yields, along with key crop management practices for reaching the best yields and the physical and socio-economic constraints of adopting these practices. This causal and hierarchical analysis of cropping system performance has the advantage of (1) preventing bias in the correlation between variables from the yield gap analysis and (2) formulating spatially targeted policies that are aimed at relaxing adoption constraints at the territorial level. After introducing the method and its different steps, we present the results of the assessment of the spatial variability in banana yields in Martinique (Caribbean). Our study has clearly shown that the planting stage is one of the most important aspects of banana production: allowing a long fallow period, plowing for soil preparation and using seedlings that are produced by tissue culture were associated with the best yields. However, several constraints limit their adoption by farmers at the regional level. The limiting factors were steep slopes, small farm size and low cash flow. We observed no relationship between pesticide use and yields. These study results finally permit the elaboration of spatially targeted policy recommendations to improve crop yields in a sustainable manner. It mainly consists in promoting and facilitating the adoption of good plantation practices for smallholders.

Increasing Crop Rotation Diversity Improves Agronomic, Economic, and Environmental Performance of Organic Grain Cropping Systems at the USDA‐ARS Beltsville Farming Systems Project

Increasing Crop Rotation Diversity Improves Agronomic, Economic, and Environmental Performance of Organic Grain Cropping Systems at the USDA‐ARS Beltsville Farming Systems Project

Agronomic and Economic Performance of Yam-Based Systems with Shrubby and Herbaceous Legumes Adapted by Smallholders

West Africa has major problems relating to the impact of slash-and-burn shifting cultivation on soil systems. In order to design more sustainable yam cropping systems, agronomy research in Benin has implemented trials in partnership with smallholders on alternative yam-based systems using shrubby (Gliricidia sepium) and herbaceous (Aeschynomene histrix) legumes. In the first phase, farmers modified these new systems within their own constraints; the systems were then further evaluated. The agronomic and economic performance of farmer-adapted alternative yam-based cropping systems and the implications for wider international application are discussed.

Cropping Systems Dynamics in the Lower Gangetic Plains of India using Geospatial Technologies

Abstract. Cropping system study is useful to understand the overall sustainability of agricultural system. Capturing the change dynamics of cropping systems, especially spatial and temporal aspects, is of utmost importance in overall planning and management of natural resources. This paper highlights the remote sensing based cropping systems change-dynamics assessment. Current study is aimed at use of multidate-multisensor data for deriving the seasonal cropping pattern maps and deriving the remote sensing based cropping system performance indicators during 1998–99 and 2004–05 in West- Bengal state of India. The temporal assessment of the changes of cropping systems components such as cropping pattern and indices for the study years 1998–99 and 2004–05 have been brought out. The results indicate that during the six years of time the kharif cropping pattern has almost remained the same, being a rice dominant system. A notable point is the decrease in the aus rice due to readjusting the cropping system practice to suit the two crop systems in many places was observed. Marginal variations in mustard and wheat areas during rabi season was observed. The boro (summer) rice area has almost remained constant. The rice-fallow-fallow (R-F-F) rotation reduced by about 4 percent while the rice-fallow-rice (R-F-R) increased by about 7 percent percent. The Area Diversity Index reduced by about 38 percent in 2004 which may be attributed to decrease in kharif pulses and minor crops during kharif and summer. However, diversity during rabi season continued to remain high. The increase in Multiple Cropping Index was observed predominantly in the southern part of the state. Cultivated Land Utilization Index shows an increase by about 0.05.

Environmental emissions profile of different sugar beet cropping systems in East of Iran

Iran is one of the main producers of sugar beet in the Middle East. Despite its great contribution to both local and global environmental impact, agricultural production systems in Iran is not very well investigated environmentally. This study characterizes some aspects of the environmental emissions inventory of sugar beet production in Iran, and compares the environmental performance of different cropping systems which include mechanized, semi-mechanized and traditional systems. Life cycle assessment methodology was used to classify and quantify the environmental emissions of sugar beet production. The life cycle inventory data reflect the cultivation profile of 93 sugar beet farms in 26 locations in Khorasan region in the east of Iran. Results of this study demonstrated that sugar beet produced in more mechanized cropping systems, can help reduce environmental emissions per functional unit. Comparing different cropping systems in each location evaluated in this study, only 19.7% of Khorasan sugar beet area performed well from the viewpoint of heavy metal emissions to water and soil, nitrate leaching and total emissions to air. The results suggest the maximum allowable levels of main environmental emissions for the discussion of improving the overall environmental profile of Iranian sugar beet, as well as these allowable levels in each cropping systems.

A Spatial Database of Cropping System and its Characteristics to Aid Climate Change Impact Assessment Studies

Cropping system study is not only useful to understand the overall sustainability of agricultural system, but also it helps in generating many important parameters which are useful in climate change impact assessment. Considering its importance, Space Applications Centre, took up a project for mapping and characterizing major cropping systems of Indo-Gangetic Plains of India. The study area included the five states of Indo-Gangetic Plains (IGP) of India, i.e. Punjab, Haryana, Uttar Pradesh, Bihar and West Bengal. There were two aspects of the study. The first aspect included state and district level cropping system mapping using multi-date remote sensing (IRS-AWiFS and Radarsat ScanSAR) data. The second part was to characterize the cropping system using moderate spatial resolution multi-date remote sensing data (SPOT VGT NDVI) and ground survey. The remote sensing data was used to compute three cropping system performance indices (Multiple Cropping Index, Area Diversity Index and Cultivated Land Utilization Index). Ground survey was conducted using questionnaires filled up by 1,000 farmers selected from 103 villages based on the cropping systems map. Apart from ground survey, soil and water sampling and quality analysis were carried out to understand the effect of different cropping systems and their management practices. The results showed that, rice-wheat was the major cropping system of the IGP, followed by Rice-Fallow-Fallow and Maize-Wheat. Other major cropping systems of IGP included Sugarcane based, Pearl millet-Wheat, Rice-Fallow-Rice, Cotton-Wheat. The ground survey could identify 77 cropping systems, out of which 38 are rice-based systems. Out of these 77 cropping systems, there were 5 single crop systems, occupying 6.5% coverage (of all cropping system area), 56 double crop systems with 72.7% coverage, and 16 triple crop systems with 20.8% coverage. The cropping system performance analysis showed that the crop diversity was found to be highest in Haryana, while the cropping intensity was highest in Punjab state.

Agronomic Performance of Cropping Systems with Contrasting Crop Rotations and External Inputs

Cropping systems with less reliance on external inputs could improve agricultural sustainability if they can produce high and stable crop yields over time. A 16‐yr experiment was conducted in southwestern Minnesota to evaluate the effects of zero external input (ZEI), low external input (LEI), high external input (HEI), and organic input (OI) systems on crop yield and yield stability in a 2‐yr soybean [Glycine max (L.) Merr.]–corn (Zea mays L.) rotation and a 4‐yr oat (Avena sativa L.)/alfalfa (Medicago sativa L.)–alfalfa–corn–soybean rotation. Oat yield was stable and highest with the LEI, HEI, and OI systems. Alfalfa yield was highest with the LEI, HEI, and OI systems in the first 8 yr and the OI system in the last 8 yr. Corn grain yield was 0, 13, 26, and 40% greater with the 4‐yr rotation than the 2‐yr rotation in the HEI, LEI, OI, and ZEI systems, respectively, and was greatest with the HEI system in the 2‐yr rotation and the LEI, HEI, and OI systems in the 4‐yr rotation. Soybean yield was 7% greater with the 4‐yr rotation than the 2‐yr rotation and was among the highest with the LEI and HEI systems. Stable corn and soybean yields occurred with the LEI and OI systems, while above‐average yield increases under favorable growing conditions occurred with the LEI and HEI systems in alfalfa and the HEI system in corn. These results demonstrate the value of extended crop rotations for corn and soybean, and that high crop yields can be obtained with reduced‐input systems.

The effect of biogas digestion on the environmental impact and energy balances in organic cropping systems using the life-cycle assessment methodology

AbstractA life-cycle assessment (LCA) was carried out to compare the environmental performance of different organic cropping systems with and without digestion of slurry and crop residues. The aims of the present study are: (1) to compare the environmental performance of organic farming dairy systems with the currently prevalent animal housing systems [solid farmyard manure (FYM) versus liquid slurry] as the main reference systems; (2) to analyze the effect of the implementation of a biogas digestion system on the consumption of fossil fuels and production of electrical energy; (3) to quantify the effects of the implementation of a biogas digestion system on the environment; and (4) to compare the obtained net energy yields with other means of obtaining energy by using the farmland area. The considered impact categories are greenhouse gas (GHG) balances, acidification, eutrophication and groundwater pollution. LCA results indicated that total emissions in systems based on FYM are much higher than in liquid slurry systems for most of the considered impact categories. The benefits of digestion of stable wastes in comparison with the reference system without digestion are mainly (1) the net reduction of the emissions of GHG and (2) energy recovery from produced biogas, while the disadvantages can be higher emissions of NH3 after spreading. The effects of additional biogas digestion of biomass such as crop residues (e.g., straw of peas and cereals) and cover crops are: (1) an optimization of the N-cycle and therewith higher yields; (2) higher energy production per unit arable land; (3) a further reduction of the GHG balance; but (4) higher N-related environmental burdens like eutrophication and acidification. The offsets of fossil fuel emissions were the largest GHG sink in most of the biogas digestion systems. The inclusion of a biogas plant into organic cropping systems and the use of the available wastes for production of energy largely increased the overall productivity of the farming system and matched very well the basic principles of organic farming such as a high self-sufficiency of the cropping system and reducing as much as possible the environmental impact of farming.

Emergy evaluation and economic performance of banana cropping systems in Guadeloupe (French West Indies)

Banana is the second most important agricultural commodity in Guadeloupe (French West Indies—FWI) and, to compensate the decline in international prices during the last 15 years, banana growers have intensified their production systems by increasing the use of technological inputs. Such intensification strategies, that require both material and investment increases, may impose economic as well as environmental risks, given the fragile island ecosystems. In order to assess the environmental performance of banana production in Guadeloupe, emergy synthesis methods were applied to six different types of banana cropping systems previously identified in the island. Additionally, aiming at improving managerial capacity and investment decision making, environmental performance results were contrasted with economic analysis for the six cropping systems. As a general outcome, these analyses showed that the better the environmental performance of the cropping system, the worse its economic performance. This result was corroborated by an increased contrast among cropping systems as related to their dependence on purchased inputs, although all cropping systems followed the same intensive and arguably wasteful agricultural model. Therefore, the analyses point out that sustainable banana production in Guadeloupe depends on a shift from the high fossil input model to a natural resources intensive one. In this sense, emergy flow analysis shows that innovation towards environmentally sound practices that would enhance nutrient cycling; integrate weeds, pests and diseases control; and improve the banana packing process might result in most positive impacts on overall sustainability. Economic analysis showed that the high labour costs contribute largely to the dependency of banana production on agricultural subsidies. However, reorienting the current European agricultural income policy to an environmental performance-based subvention might be a policy opportunity to achieve the present social goals while promoting sustainability in banana production. Furthermore, the EC regulation on quality standards for commercial bananas, by imposing strict aesthetic benchmarks, has a negative effect on the sustainability of banana production because substantial non-renewable and purchased emergy inflows into banana production systems aim to improve aesthetic standards over sound ecological management.

Methodological progress in on-farm regional agronomic diagnosis. A review

The development of sustainable cropping systems is a key priority for agronomists and crop scientists. A first step involves understanding the relationship between cropping system performance and farmers’ practices. To complete this step, a methodological framework entitled Regional Agronomic Diagnosis (RAD) has been developed. During the last ten years, the scope of the regional agronomic diagnosis has been enlarged to include several factors describing crop quality and the environmental impact of cropping systems. Regional agronomic diagnosis has led to several major advances such as (1) the assessment of the effect of preceding crop and soil structure on malting barley quality in France and (2) the assessment of the effects of ploughing, nematicide use and fertilisers on soil properties in intensive banana plantations in the West Indies. Improvements have also been gained in methodology, particularly by the selection of indicators for assessing the effects of crop management, soil and weather conditions, and data analysis. Finally, regional agronomic diagnosis has been integrated into more general approaches of agricultural development. We review here this methodological progress.

Evaluating spatial within plot crop variability for different management practices with an optical sensor?

It is essential to have an indication of the sustainability of an agricultural system in addition to the potential, immediate benefits well before the catastrophic consequences of non-sustainability become apparent. Long-term experiments are best suited to test sustainability of a given system. This paper has a dual objective: (1) evaluate the Greenseeker handheld NDVI sensor as a tool for measuring within plot spatial variability, (2) address the question whether different management practices affect spatial within-plot crop growth variability and what this spatial variability tells us about the cropping system performance. Therefore, spatial and time variability of crop performance were measured during the 2004 and 2005 crop cycle for all plots of the different management treatments of a long-term (started 1991) tillage and residue management trial. The NDVI readings measured with the handheld sensor correlated well with the visual scoring in the field. The hand-held sensor is time-efficient and gave reproducible results. The potential for using this tool to detect spatial crop variability, both within and between plots/treatments, is promising. The coefficient of variation (CV) for the NDVI measurement sequence in each plot was determined. The CV’s throughout the crop season reflected the canopy expansion and senescence curve of maize and wheat. The CV was high at the beginning of the crop season, however, once the canopy began to close, leaves from larger plants covered the leaves and whorl of smaller plants, extending further into the linear row. Measurements to investigate spatial variability related to crop performance should thus be done after this initial stage at the end of the vegetative period when the vegetative biomass of the crops is fully established. Zero tillage systems without surface residue retention produced high CVs of the NDVI sequence and high spatial crop variability throughout the season, even after the vegetative period. As the only factors differing between the different plots are the tillage/residue/rotation practices and as similar patterns were found for all plots representing repetitions of the same management practice (zero tillage without residue retention), increased variability is an indicator of agronomic mismanagement or, conversely, of sound agriculturally production practices.

The performance of organic and conventional cropping systems in an extreme climate year

AbstractThe 1999 severe crop season drought in the northeastern US was followed by hurricane-driven torrential rains in September, offering a unique opportunity to observe how managed and natural systems respond to climate-related stress. The Rodale Institute Farming Systems Trial has been operating since 1981 and consists of three replicated cropping systems, one organic manure based (MNR), one organic legume based (LEG) and a conventional system (CNV). The MNR system consists of a 5-year maize–soybean–wheat–clover/hay rotation, the LEG of a 3-year maize–soybean–wheat–green manure, and the CNV of a 5-year maize-soybean rotation. Subsoil lysimeters allowed quantification of percolated water in each system. Average maize and soybean yields were similar in all three systems over the post-transition years (1985–1998). Five drought years occurred between 1984 and 1998 and in four of them the organic maize outyielded the CNV by significant margins. In 1999 all crop systems suffered severe yield depressions; however, there were substantial yield differences between systems. Organic maize yielded 38% and 137% relative to CNV in the LEG and MNR treatments, respectively, and 196% and 152% relative to CNV in the soybean plots. The primary mechanism of the higher yield of the MNR and LEG is proposed to be the higher water-holding capacity of the soils in those treatments, while the lower yield of the LEG maize was due to weed competition in that particular year and treatment. Soils in the organic plots captured more water and retained more of it in the crop root zone than in the CNV treatment. Water capture in the organic plots was approximately 100% higher than in CNV plots during September's torrential rains.

Evaluation of oilseed crop rotations with agro-environmental indicators

The European Common Agricultural Policy is shifting an increasing part of the subsidies to eco-conditionality. Henceforth, it becomes essential to evaluate the environmental effect of agricultural practices, and more generally performances of cropping and farming systems, in order to design and to develop more sustainable systems. This assessment is being implemented for the main cropping systems of some French regions, using environmental indicators. Eleven exposure indicators were chosen in order to represent a wide range of specific sustainability objectives dealing with water, soil, air, non-renewable resources, biodiversity, and landscape. The results present the sustainability assessment for the crop rotations of Champagne Berrichonne region in the Centre of France.

Producing Soybean and Wheat Cropping Systems in Rainfed Environments

Growers are interested in crops that can be used as alternatives to complement winter wheat grown as a monocrop. The objective of this study was to compare agronomic performance and net return of winter wheat and soybean cropping systems under rainfed environments. Cropping systems of monocrop winter wheat (Triticum aestivum L.), monocrop soybean [Glycine max (L.) Merr.], and 3-crop/2-year (early-season soybean, winter wheat, and doublecrop soybean in a biennial rotation) were evaluated at Lahoma, OK. Over three years, early-season and monocrop soybean yields averaged 35 and 31 bu/acre, respectively, but were not significantly different in any year. Doublecrop soybean averaged 13 bu/acre following wheat. Reduced yields for doublecrop soybean were attributed primarily to highly variable rainfall amount and distribution during growing seasons. Wheat yields were similar for monocrop and 3-crop/2-year systems, averaging 54 and 53 bu/acre, respectively. Crop production reflected the rainfall variability occurring in such a production environment. Enterprise budgeting was used to determine revenues, costs, and net returns for cropping systems. Annualized average net returns to land, labor, and management were $59/acre for monocrop soybean, $52/acre for monocrop winter wheat, and $77/acre for 3-crop/2-year. The results can be used as a tool to determine cropping systems to use in managing crop production.