1,720,976 research outputs found
Replication Data for: Nitrogen dynamics and yields of fresh bean and sweet corn with different cover crops and planting dates
No full textThe objective of this study was to determine the impact of cover crop species and planting date on (1) fresh bean and sweet corn yield and (2) N dynamics
Impact of Legume Cover Crops on Nitrogen Dynamics and Yield in Commercial Corn Systems in Southern Ontario
No full textNitrogen contribution of a legume cover crop (cc) to subsequent field corn (Zea mays L.) may reduce nitrogen (N) inputs. Since best management options are largely unknown, a study was conducted in 2012-2013 and 2013-2014 to assess N dynamics and yield in cc-corn rotations, under different management regimes, compared to no-cc plots. In October soil mineral N (SMN) was 10 kg N ha-1 lower for the cc treatments compared to no-cc. In May, in spring-terminated plots, plant available N (PAN) was 20 kg N ha-1 lower in no-cc compared to alfalfa and red clover plots. At corn harvest, PAN and yield were significantly higher in the 13.5 kg ha-1 cc seeded plots compared to the 3.4 kg ha-1 seeded plots. Planting of red clover or alfalfa at a 6.7 kg ha-1 seeding rate, combined with spring termination is recommended to maximize N availability in corn cropping systems
Nitrogen cycling and weed dynamics in a pea-cover crop-sweet corn rotation
No full textThe effect of cover crops on N and weed dynamics was assessed within a pea ('Pisum sativum' L.) - cover crop - sweet corn (' Zea mays' L.) rotation. Cover crops of oat ('Avena sativa' L.), perennial rye (rye) ('Secale cereale' L.), oilseed radish (OSR) ('Raphanus sativus' L. var. oleoferus Metzg Stokes), and OSR plus perennial rye (OSR+rye) increased plant available N (PAN) over the cover crop growing season compared to the no cover control at the Bothwell site only. However, at neither site did cover crops result in increased PAN for the sweet corn, indicating that these cover crops will not reduce required N fertilizer applications. Also, cover crops posed neither an increased or decreased need for weed management during sweet corn production. However, OSR may be useful in pesticide reduced programs due to its potential ability to reduce fall herbicide applications, provided it does not set viable seed
Nitrogen dynamics as affected by cover crop type, planting date and rye biomass spring removal in a cover crop-cucumber rotation
Get PDFThe effects of cover crop type, planting date (early-August and early-September) and cereal rye ('Secale cereale' L.) spring biomass removal in a cucumber ('Cucumis sativus' L.)-cover crop-cucumber rotation on N dynamics were investigated from 2008-2010. Relative to no cover crop (NoCC), cover crops of rye, oats ('Avena sativa' L.), oilseed radish (OSR) ('Raphanus raphanistrum' [L.] var. ' oleiferus' Metzg Stokes) and forage peas ('Pisum sativum' L.) consistently increased plant available N (PAN) during the cover crop growing season, while hairy vetch ('Vicia villosa' L.) had no effect. Differences among planting dates during the fall did not translate into differences in PAN during the cucumber season. Higher PAN in the NoCC+84 kg N ha -1 did not result in higher cucumber marketable yield income compared to OSR and pea in 2009 and all treatments in 2010. Leachate samples in lysimeters were sporadic but generally supported cover crop N dynamics observed over the rotation
Evaluation of Optical Sensors in Predicting Root Yield, Quality and Nitrogen Application in Sugarbeet (Beta vulgaris L.)
No full textNitrogen management is critical for sugarbeets (Beta vulgaris L.) because it inversely influences root and sucrose yields. From 2015-2017 in Southwestern Ontario this study evaluated the use of optical sensors (SPAD, GreenSeeker) throughout the growing season as a method to guide nitrogen application and harvest date selection by predicting root and sucrose yields. Nitrogen rates (4-5) and cultivars (8-12) were tested in a split block design (3-replications). In all years, few cultivars (≤2) had a root yield response to applied N, which was attributed to high inherent soil fertility. The optimal N rate for sucrose and profits was zero due their negative correlations. Optical sensors correlated negatively with sucrose across the majority (>60%) cultivars tested in September but not at other times. Thus, both sensors are recommended for use in September to predict sucrose yield and to alter harvest date to maximize profits but not to adjust fertilizer N applications.Michigan Sugar Company Inc.Ontario Sugarbeet Growers AssociationOntario Agri-Food Innovation Allianc
Effect of Cover Crops and Nitrogen Fertilizer Management on Corn Production: Nitrous Oxide Emissions and Grain Yield
No full textCover crops and improved nitrogen management practices have potential to improve corn production and reduce nitrous oxide emissions, however these management strategies have yet to be evaluated together. Thus, the objective of this study was to evaluate the effect of cover crops (no cover crop, red clover, 4-species mix) and nitrogen management (no nitrogen, urea, urea + dual inhibitor, split application + dual inhibitor) on corn production and nitrous oxide emissions in Ontario. Static non-steady state flux chambers were utilized to measure nitrous oxide emissions at two sites in Southern Ontario. Ridgetown (clay loam soil) saw much larger growing season emissions than Elora (loam soil) (20.8 kg N2O-N ha-1 and 1.15 kg N2O-N ha-1 respectively). Cover crops and nitrogen management had significant effects on nitrous oxide emissions and grain corn yields but were not consistent among locations. This signifies the need for further research under different environmental conditions
Plant Density, Harvest Date, and Fertilizer Impact on Sugarbeet (Beta vulgaris L.) Root and Sucrose Yield, N Dynamics, and Profit Margins
No full textLocal (southwestern Ontario and Michigan) sugarbeet production practices have changed to an earlier harvest date (early/mid Sept. vs. late Oct. early Nov.) and increased plant density (114, 800 plants ha-1 at 57 cm vs. 86, 500 plants ha-1 at a row width of 76 cm) using high yielding glyphosate-resistant sugarbeet varieties. In addition, crop consultants have recommended including N fertilizer in a 5-by-5 cm band during sugarbeet planting. Nutrient management is an essential aspect of crop production, and more specifically, in sugarbeet production as quality and root yield are negatively and positively, respectively, influenced by N fertility. Therefore, the effects of these changes in crop production practices on root and sucrose yield, profit margins, N dynamics, and nitrogen use efficiency (NUE) were evaluated at two fields in 2013-2015 with two harvest dates. Application rates of 157 kg N ha-1 to optimize root yield but only 12 kg N ha-1 to optimize recoverable white sucrose per tonne (RWST) were observed at either harvest date. Conversely, profit margins calculated using Michigan Sugar Company (MSC) 5-year average payment standards favour an optimal profit margin application rate of 127-136 kg N ha-1 for early and late harvest, respectively. The effect of harvest date and N and P fertilizer placement, source, and timing was not influential on NUE and N loss indicators and a lack of difference between NUE indices and yield slightly favoured the application of N and P in a 5-by-5 cm band at planting together or alone compared to the zero N-P control. Therefore, results do not contradict current industry recommendations; however, there is no compelling evidence to suggest farmers should modify planters to include N fertilizer at planting unless already capable. Further, plant density and harvest date had no influence on N fertilizer requirements tor most profitable rate of N. However, an early harvest resulted in lower root yield, RWST, and N removal from the field. It is therefore recommended that, under current payment protocols, N fertilizer should be applied at rates 27-57 kg N ha-1 greater than the current application of 100 kg N ha-1 and can be applied at the same rate regardless of harvest date or plant density. However, NUE calculations suggest that an earlier harvest may result in higher risk of N losses compared to late, and as such, growers may wish to harvest later or consider implementing N loss mitigation strategies
Long-term vs. first-time vs. no cover cropping: towards understanding nitrogen availability to corn (Zea Mays L.) and soil organic carbon sequestration
No full textUsing cover crops (CC) is a management practice touted for reducing synthetic fertilizer inputs and mitigating global warming, largely due to nitrogen (N) availability improvement and soil organic carbon (SOC) sequestration. These benefits are usually detected after long-term use of CC (LTCC), limiting our understanding of mechanisms of delivering N to subsequent crops and affecting SOC storage in deeper soil layers. Therefore, a LTCC experiment, established in 2007/2008 (Ridgetown, Ontario, Canada), was employed to establish long-term vs. first-time vs. no cover cropping (LTCC vs. FTCC vs. NOCC) treatments in the same field, in 2021/2022. Two critical questions were answered: (1) does soil organic matter (SOM) accrual increase N availability to corn (Zea mays L.) under LTCC and what are the mechanisms? and (2) how does LTCC affect SOC and total N (TN) storage within soil profile and what are the possible mechanisms? Firstly, a 15N-labelled fertilizer (99% enriched 15N ammonium sulfate at 12 kg N ha–1) was applied to all treatments (one week after CC planting) and traced into grain corn at harvest. About 60% of applied 15N were unaccounted for NOCC at all sampling times, while the LTCC and FTCC had similar ability to transfer 15N from the CC-soil system to the corn-soil system, due to their equal CC biomass productivity. This 15N study demonstrated that cover cropping could improve N availability to subsequent year’s crops by scavenging soil residual N, decomposing CC, and increasing SOM accumulation (esp. particulate organic matter). Secondly, we collected soil samples to 120 cm depth under LTCC and found LTCC had greater SOC (22%) and TN (26%) stocks to 120 cm depth than NOCC. However, SOC stored more in particulate organic matter fraction at 0–30 cm depth but more in mineral-associated organic matter fraction at 30–90 cm depth. Also, 19 LTCC experiments demonstrated that integrating non-legume CC into diverse crop rotations likely improves soil C sequestration across North America. Combined, the research highlighted the long-term use of CC is important for simultaneously improving N availability and soil C storage, thereby achieving sustainable agriculture with reduced N fertilizer inputs.Ontario Ministry of Farming, Agriculture and Agribusiness and Ministry of Rural AffairsGrain Farmers of OntarioOntario Agri-Food Innovation Allianc
Impact of Previous Cover Crops and Corn Stover Removal on Soil Organic Carbon, Aggregate Stability and Squash Yield
No full textCorn stover removal for biofuel production can have a negative effect on crop yield and/or soil quality. Cover crops may offer an opportunity to improve or maintain soil quality within corn stover removal systems. This research assessed the effects of cover crops systems and corn stover removal on soil aggregate stability, squash (Cucurbita pepo var. pepo cv. Autumn Delight) fruit yield, and soil carbon and nitrogen dynamics. Diffuse reflectance infrared Fourier-transform (DRIFT) spectroscopy was used to semi-quantitatively assess soil organic matter decomposition from soil amended with oat (Avena sativa L.), cereal rye (Secale cereale L.), oilseed radish (Raphanus sativus L. var. oleoferus Metzg. Stokes) (OSR), and a mixture of oilseed radish and cereal rye (OSR+rye), with and without corn stover by measuring polysaccharide-C bands regularly over a 72 d incubation study, and comparing first-order model parameters to evolved C. One year after corn stover removal in cover crop systems there were no differences in soil aggregate stability and clay dispersibility. Squash vegetable yield was also not affected by corn stover removal after one year. Results showed that all cover crop-corn stover treatment combinations had a significantly lower polysaccharide decomposition and C mineralization rates compared to the no cover treatment. Thus, although subsequent crop yield was not impacted, this study suggests that these cover crops, in particular OSR and OSR+rye, have the potential, in the short-term, to replenish labile organic C pools and to reduce C losses when compared to the no cover control treatment.Ontario Ministry of AgricultureOntario Ministry of Rural AffairsOntario Processing Vegetable Grower
Cover crop impacts on soil health, carbon mineralization, and crop yield: Insights from a long-term field experiment and an incubation study
Get PDFThis study builds upon previous research conducted at a long-term cover crop experiment in Ridgetown, Ontario, which demonstrated enhanced surface soil health and crop yields. Here, we explored the link between soil health and crop yield while studying carbon cycling with long-term cover crop management and crop residue amendments. Consistent with our previous studies, use of a long-term cover crop (grown nine times over twelve years) significantly enhanced some soil health indicators. Principal component analysis identified water-extractable carbon, potentially mineralizable nitrogen, mesoporosity, clay content, and acid phosphatase enzyme activity as important indicators. Path analysis revealed that acid phosphatase had a significant positive and direct effect on crop yield. In laboratory incubation experiments, soil from long-term Radish+Rye plots and crop residue amendments increased soil respiration, but not aggregate stability. These findings contribute to our understanding of long-term cover cropping in promoting soil health and carbon dynamics, thereby contributing agricultural sustainability
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