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J. Salette - One of the best experts on this subject based on the ideXlab platform.
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Kinetic parameters of nitrate uptake by different catch crop species: effects of low temperatures or previous nitrate starvation
Physiologia Plantarum, 1993Co-Authors: P. Lainé, Alain Ourry, J. H. Macduff, Jean Boucaud, J. SaletteAbstract:The pollution of aquifers by NO−3 in temperate environments is aggravated by farming practices that leave the ground bare during winter. The use of catch crops during this time may decrease nitrate loss from the soil. Nitrate uptake by several catch crop species (Brassica napus L., Sinapis alba L., Brassica rapa L., Raphanus sativus L., Trifolium alexandrinum L., Trifolium incarnatum L., Phacelia tanacetifolia Benth., Lolium perenne L., Lolium multiflorum Lam. and Secale cereale L.) was here studied in relation to transpiration rate and low temperatures applied to the whole plant or to roots only. The Michaelis constant (Km), maximum uptake rate (Vmax), time of induction and contributions of inducible and constitutive mechanisms were estimated from measurements of NO−3 depletion in the uptake medium. There were large differences between species, with Km (μM) values ranging between 5.12 ± 0.64 (Trifolium incarnatum) and 36.4 ± 1.97 (Lolium perenne). Maximum NO−3 uptake rates expressed per unit root weight were influenced by ageing, temperature and previous NO−3 nutrition. They were also closely correlated with water flow through the roots and with shoot/root ratio of these species. The combined results from all species and treatments showed that Vmax increased with shoot/root ratio, suggesting a regulatory role for the shoots in NO−3 uptake. Overall, the results showed a great diversity in NO−3 uptake characteristics between species in terms of kinetic parameters, contribution of the constitutive system (100% of total uptake in ryegrass, nil in Fabaceae) and time of induction.
M. G. Wagger - One of the best experts on this subject based on the ideXlab platform.
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Crimson Clover Management to Enhance Reseeding and No‐Till Corn Grain Production
Agronomy Journal, 1993Co-Authors: Noah N. Ranells, M. G. WaggerAbstract:Economic savings and increased legume-N use efficiency may result from natural reseeding of winter annual legume cover crops. A 3-yr experiment was conducted on a Cecil fine sandy loam (clayey, kaolinitic, thermic Typic Kanhapludult) to examine the effects of crimson clover (Trifolium incarnatum L.) strip desiccation width (25, 50, and 75% of row area) and orientation (parallel or perpendicular to plant row) on soil water depletion, corn (Zea mays L.) growth and grain yield, and clover reseeding. Additional treatments included early desiccation (25% parallel strip 2 wk before corn planting), annual seeding (complete desiccation at corn planting), and mechanical disruption of clover growth by the no-tillage planter []
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Crimson Clover Reseeding Potential as Affected by s‐Triazine Herbicides
Journal of Production Agriculture, 1993Co-Authors: Noah N. Ranells, M. G. WaggerAbstract:Economic savings can result from allowing a crimson clover (Trifolium incarnatum L.) cover crop in no-tillage corn (Zea mays L.) systems to self-reseed and thereby eliminate the need for annual seeding operations. Research has indicated, however, that self-reseeding of crimson clover is variably sensitive to certain residual corn herbicides, depending on growth stage at time of herbicide application. Accordingly, a 2-yr experiment was conducted to evaluate the effects of atrazine, cyanazine, and simazine applied to crimson clover at four growth stages (late vegetative, early bloom, late bloom, and early seed set) on subsequent clover reseeding potential. All successfully reseeded crimson clover plots were sampled in 1990 and 1991 for dry matter (DM) and total N concentration []
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Nitrogen release from crimson clover in relation to plant growth stage and composition
Agronomy Journal, 1992Co-Authors: Noah N. Ranells, M. G. WaggerAbstract:Increased N-use efficency and economic savings may result from a better understanding of N release patterns from legume residues. A 2-yr field experiment was conducted on a Cecil fine sandy loam (clayey, kaolintic, thermic Typic Kanhapludult) to examine the effects of crimsom clover (Trifolium incarnatum L.) growth stage on dry matter accumulation, N concentration, and chemical composition in relation to N release under no-tillage management. Crimson clover was harvested in the spring at four growth stages (late vegetative, early bloom, late bloom, and early seed set) (...)
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Reseeding Potential of Crimson Clover as a Cover Crop for No‐Tillage Corn
Agronomy Journal, 1991Co-Authors: J. L. Myers, M. G. WaggerAbstract:Leguminous cover crops can provide biologically fixed N to a subsequent corn (Zea mays L.) crop as well as erosion control and moisture conserving mulch, but establishment is costly and often unsuccessful. A field experiment was conducted for 3 yr to determine the self-reseeding potential of crimson clover (Trifolium incarnatum L.) and its N contribution in a no-tillage corn production system. Four cover crop management treatments (fallow, annual-seeded, volunteer-reseeded, and volunteer strip-reseeded) were combined factorially with four fertilizer-N rates (0, 50, 100, or 150 kg ha −1 ) applied to the subsequent corn crop (...)
P. Lainé - One of the best experts on this subject based on the ideXlab platform.
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Kinetic parameters of nitrate uptake by different catch crop species: effects of low temperatures or previous nitrate starvation
Physiologia Plantarum, 1993Co-Authors: P. Lainé, Alain Ourry, J. H. Macduff, Jean Boucaud, J. SaletteAbstract:The pollution of aquifers by NO−3 in temperate environments is aggravated by farming practices that leave the ground bare during winter. The use of catch crops during this time may decrease nitrate loss from the soil. Nitrate uptake by several catch crop species (Brassica napus L., Sinapis alba L., Brassica rapa L., Raphanus sativus L., Trifolium alexandrinum L., Trifolium incarnatum L., Phacelia tanacetifolia Benth., Lolium perenne L., Lolium multiflorum Lam. and Secale cereale L.) was here studied in relation to transpiration rate and low temperatures applied to the whole plant or to roots only. The Michaelis constant (Km), maximum uptake rate (Vmax), time of induction and contributions of inducible and constitutive mechanisms were estimated from measurements of NO−3 depletion in the uptake medium. There were large differences between species, with Km (μM) values ranging between 5.12 ± 0.64 (Trifolium incarnatum) and 36.4 ± 1.97 (Lolium perenne). Maximum NO−3 uptake rates expressed per unit root weight were influenced by ageing, temperature and previous NO−3 nutrition. They were also closely correlated with water flow through the roots and with shoot/root ratio of these species. The combined results from all species and treatments showed that Vmax increased with shoot/root ratio, suggesting a regulatory role for the shoots in NO−3 uptake. Overall, the results showed a great diversity in NO−3 uptake characteristics between species in terms of kinetic parameters, contribution of the constitutive system (100% of total uptake in ryegrass, nil in Fabaceae) and time of induction.
A M Decker - One of the best experts on this subject based on the ideXlab platform.
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Legume Cover Crop Contributions to No-Tillage Corn Production
Agronomy Journal, 1994Co-Authors: A M Decker, John J. Meisinger, Andrew J. Clark, F. Ronald Mulford, Marla S. McintoshAbstract:Winter cover crops can supply N to the next crop, reduce erosion and N leaching, and conserve or deplete soil moisture. To identify optimum corn fertilizer nitrogen (FN) rates following cover crops, we evaluated hairy vetch (VT: Vicia villosa Roth), Austrian winter pea [PE: Pisum sativum L. subsp. sativum var. arvense (L.) Poir.], crimson clover (CR: Trifolium incarnatum L.), and wheat (WH: Triticum aestivum L.) winter cover crops in the U.S. Coastal Plain and Piedmont for no-tillage corn (Zea mays L.) at four FN rates (topdressed NH 4 NO 3 ) over 4 yr. Parameters evaluated included cover crop yield and N content, corn N uptake, and corn grain yield [...]
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conserving residual corn fertilizer nitrogen with winter cover crops
Agronomy Journal, 1992Co-Authors: P R Shipley, J J Messinger, A M DeckerAbstract:Autumn residual fertilizer nitrogen (FN) can be easily leached into groundwater in humid climates. Winter cover crops were evaluated for their ability to assimilate residual corn FN and thereby reduce N losses. Labelled FN ( 15 N depleted) was applied to corn in Maryland in 1986 and 1987 at rates of 0, 168, and 336 kg FN ha #751 on a Mattapex silt loam (fine-loamy, mixed, typic Hapludult). Cover crop treatments following corn harvest were hairy vetch (Vicia villosa Roth), crimson clover (Trifolium incarnatum L.), cereal rye (Secale cereale L.), or annual ryegrass (Lolium multiflorum Lam.), and a weed/fallow control of chickweed (Stellaria media L.) (...)
Harry H Schomberg - One of the best experts on this subject based on the ideXlab platform.
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Conservation Tillage and Cover Crop Influences on Cotton Production on a Southeastern U.S. Coastal Plain Soil
2014Co-Authors: Harry H Schomberg, Richard G. Mcdaniel, Eddie Mallard, Dinku M. Endale, Dwight S. Fisher, Miguel L. CabreraAbstract:Understanding cover crop and tillage system interactions within specific environments can help maximize productivity and economic returns of cotton (Gossypium hirsutum L.) produced on sandy coastal plain soils of the southeastern USA. A strip-plot design with three replications was used to evaluate the cover crops Austrian winter pea [Pisum sativum L. ssp. arvense (L.)], balansa clover (Trifolium michelianum Savi), crimson clover (Trifolium incarnatum L.), hairy vetch (Vicia villosa Roth subsp. villosa), oil seed radish (Raphanus sativus L.), black oat (Avena strigosa Schreb.), and rye (Secale cereale L.) and tillage (strip and none) influences on cotton grown on a Bonifay fine sand (loamy, siliceous, subactive, thermic Grossarenic Plinthic Paleudults) nearWaynesboro,GA from 1999 to 2003. Drought influenced production 3 of 4 yr. Cover crop biomass was greatest from rye, intermediate from black oat, oilseed radish, hairy vetch, and Aus
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cover crop effect on soil carbon fractions under conservation tillage cotton
Soil & Tillage Research, 2007Co-Authors: Upendra M Sainju, Wayne F Whitehead, Bharat P Singh, Glynn P Tillman, Harry H Schomberg, Sharon L LachnichtweyersAbstract:Cover crops may influence soil carbon (C) sequestration and microbial biomass and activities by providing additional residue C to soil. We examined the influence of legume [crimson clover (Trifolium incarnatum L.)], nonlegume [rye (Secale cereale L.)], blend [a mixture of legumes containing balansa clover (Trifolium michelianum Savi), hairy vetch (Vicia villosa Roth), and crimson clover], and rye + blend mixture cover cropson soil C fractions at the0‐150 mmdepth from 2001 to 2003. Active fractions of soil C includedpotentialCmineralization(PCM)andmicrobialbiomassC(MBC)andslowfraction assoilorganicC(SOC).Experiments were conducted in Dothan sandy loam (fine-loamy, kaolinitic, thermic, Plinthic Kandiudults) under dryland cotton (Gossypium hirsutum L.) in central Georgia and in Tifton loamy sand (fine-loamy, siliceous, thermic, Plinthic Kandiudults) under irrigated cotton in southern Georgia, USA. Both dryland and irrigated cotton were planted in strip tillage system where planting rows were
