Nitrogen Contribution of Legume/Cereal Mixed Cover Crops and Organic Fertilizers to an Organic Broccoli Crop

Legume/cereal mixed winter cover crops are commonly used by organic growers on the central coast of California, but they are unable to provide sufficient nitrogen (N) for a high N-demanding vegetable crop such as broccoli and supplemental fertilizer application may be necessary. The goals of this project were to evaluate the contribution of N from a mixed legume/cereal cover crop (CC) and feather meal and blood meal as organic fertilizers (OF) to an organic broccoli crop and to evaluate economic benefits of CC and OF to the subsequent organic broccoli crop. Trials were conducted at two sites (A and B) with different management histories. Cover crops were grown over the winter and incorporated into the soil in the spring and subsequently broccoli [Brassica oleracea L. (Italica group)] was grown in 2006 at both sites and in 2007 at B only. Cover crop and no CC treatments were grown with supplemental organic fertilizers at four fertility levels (0, 84, 168, and 252 kg N/ha of OF) with four replicates. Generally broccoli head yields at A (14.9 to 26.3 Mg·ha−1) were higher than at B (0.7 to 17.4 Mg·ha−1 in 2006 and 5.5 to 17.9 Mg·ha−1 in 2007). Yield and aboveground biomass N were significantly increased by OF at rates up to 168 kg N/ha at A and to 252 kg N/ha at B and by CC in 2006 at both sites but not in 2007 at B. Although N content of the CC was similarly low at A (2006) and at B (2007), immobilization of soil mineral N occurred only at B. This suggests that the addition of a low N content CC was offset by high N mineralization from the soil at A with a long organic management history (greater than 33 years). Supplemental fertilizer applications may be necessary to achieve optimal yields, but the amount needed can be reduced by cover cropping in fields with a long history of cover crop-based organic management (A) or when cover crop N content is sufficiently high to prevent immobilization (B, 2006). Soil NO3-N patterns suggest a pre-side dress nitrate test may also be useful for N management in organic broccoli. Use of cover crops increased net return above harvest and fertility costs when the yield reduction by N immobilization did not take place. However, the net return increase by the use of cover crops tended to diminish as the rate of OF application increased.

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Cover cropping in Vitis vinifera L. cv. Manto Negro vineyards under Mediterranean conditions: effects on plant vigour, yield and grape quality

OENO One ◽

10.20870/oeno-one.2011.45.4.1501 ◽

2011 ◽

Vol 45 (4) ◽

pp. 223 ◽

Cited By ~ 5

Author(s):

Alícia Pou ◽

Javier Gulías ◽

Maria Moreno ◽

Magdalena Tomàs ◽

Hipolito Medrano ◽

...

Keyword(s):

Stomatal Conductance ◽

Cover Crops ◽

Cover Crop ◽

Yield Reduction ◽

Growth Stages ◽

Plant Vigour ◽

Cover Cropping ◽

Permanent Resident ◽

Grape Quality ◽

Intrinsic Water Use Efficiency

Aims: In temperate climates, cover crops are mainly used to reduce excess soil water and nutrient availability to grapevines, which otherwise could decrease grape quality. In Mediterranean climates, where water is a limiting factor, the use of cover crops is not as straightforward. However, in this scenario, summer senescent and self-seeding herbaceous cover crops could also help to decrease soil erosion as well as to reduce excessive early vegetative vigour, which could restrict grape water availability at later phenological stages. The aim of this experiment was to study the effects of particular cover crops in Mediterranean vineyards on grapevine vegetative growth, gas exchange, yield and grape quality.Methods and results: The experiment was carried out over three consecutive years in an organic vineyard (cv. Manto Negro) in central Majorca, Spain. Three treatments (three cover cropping rows per treatment) were established: perennial grass and legume mixture (PM), no tillage, i.e., with permanent resident vegetation (NT), and traditional tillage or ploughed soil (TT). The grapevines were rain fed until veraison, and then drip irrigation was applied (30% potential evapotranspiration; ETP) until harvest. Plant water status was established according to a defined value of maximum daily leaf stomatal conductance (gs). Cover crops reduced total leaf area (LA), gs and grapevine vigour at early growth stages. gs and net photosynthesis (AN) were higher in cover crop treatments during the veraison and ripening stages, likely because of the reductions in LA. Intrinsic water use efficiency increased from flowering to veraison-maturity in all treatments. Yield was lower in the cover crop treatments (PM and NT) compared to TT for all years, but these differences were only significant in 2007. However, grape quality parameters slightly improved in the PM treatment.Conclusion: The use of cover crops decreased LA, helping to avoid dramatic reductions of stomatal conductance in mid-summer, but decreased yield and only slightly increased grape quality.Significance and impact of the study: This study showed that the use of specific cover crops in vineyards under Mediterranean climates helps to reduce vegetative vigour. Nevertheless, yield reduction and slight quality improvement suggest that cover crops should be adjusted in order to reduce competition for water and thus prevent these negative effects of water scarcity.

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Effects of Organic Fertilization and Cover Crops on an Organic Pepper System

HortTechnology ◽

10.21273/horttech.18.2.215 ◽

2008 ◽

Vol 18 (2) ◽

pp. 215-226 ◽

Cited By ~ 15

Author(s):

K. Delate ◽

C. Cambardella ◽

A. McKern

Keyword(s):

Soil Fertility ◽

Cover Crops ◽

Cover Crop ◽

Crop Production ◽

Large Scale ◽

Soil Analysis ◽

Organic Fertilizer ◽

The United States ◽

Organic Fertilizers ◽

Organic Farm

With the continuing 20% growth rate in the organic industry, organic vegetable crop production has increased to 98,525 acres in the United States. The requirement for certified organic vegetable producers to implement a soil-building plan has led to the development of soil fertility systems based on combinations of organic fertilizers and cover crops. To determine optimal soil fertility combinations, conventional and organic bell pepper (Capsicum annuum) production was evaluated from 2001 to 2003 in Iowa, comparing combinations of two synthetic fertilizers and three compost-based organic fertilizers, and a cover crop treatment of hairy vetch (Vicia villosa) and rye (Secale cereale) in a strip-tilled or fully incorporated cover crop system. Organic pepper growth and yields equaled or surpassed conventional production when nitrogen (N) was provided at 56 or 112 kg·ha−1 from compost-based organic fertilizer. Soil analysis revealed higher N in plots where cover crops were tilled compared with strip-tilled plots, leading to recommendations for sidedressing N in strip-tilled organic pepper production. Increased incidence of disease was also detected in strip-tilled plots. Postharvest weight loss after 6 weeks in storage was similar in organic and conventional peppers. The addition of calcium and sulfur products in conventional or organic fertilizer regimes did not increase pepper production or postharvest storage potential. Despite application challenges, cover crops will remain as critical components of the organic farm plan for their soil-building benefits, but supplementation with approved N sources may be required for optimal pepper production. Organic growers should conduct their own tests of organic-compliant soil amendments to determine cost effectiveness and value for their site before large-scale application.

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Organic Fertilization, Green Manure, and Vetch Mulch to Improve Organic Zucchini Yield and Quality

HortScience ◽

10.21273/hortsci.48.8.1027 ◽

2013 ◽

Vol 48 (8) ◽

pp. 1027-1033 ◽

Cited By ~ 35

Author(s):

Francesco Montemurro ◽

Angelo Fiore ◽

Gabriele Campanelli ◽

Fabio Tittarelli ◽

Luigi Ledda ◽

...

Keyword(s):

Cover Crop ◽

Green Manure ◽

Organic Fertilizer ◽

Organic Fertilizers ◽

Residue Management ◽

First Year ◽

N Fixation ◽

Fertilization Program ◽

Mineral N ◽

Yield And Quality

A 2-year field experiment was carried out in a Mediterranean environment to study the effects of vetch (Vicia sativa L.) residue management strategies incorporating green manure (GM) using a roller-crimper (RC) and different organic fertilizers (municipal solid waste compost, anaerobic digestate, and a commercial organic fertilizer) on organic zucchini (Cucurbita pepo L.) yield and quality. Zucchini yield was influenced positively by the vetch residue management strategy, although the response was significantly different between years. The vetch cover crop increased marketable zucchini yield in the first year by 46.6% compared with the fallow (FA) treatment, indicating that this fertility-building crop could reduce off-farm nitrogen (N) fertilizer input for subsequent crops. Averaging over 2 years of the experiment, marketable zucchini yield increased by 15.2% and 38% with the RC mulch and GM plow-down, respectively, compared with the FA treatment, although differences were significant in the first year only. The application of organic fertilizers in vetch management plots increased marketable zucchini yield by 21.8% in the first year compared with the unfertilized control. This result is particularly relevant, because organic fertilizers were applied at ≈50% of the normal application rate for zucchini after taking into account biological N fixation attributable to the vetch. The concentrations of soil mineral N at harvest were 19, 27, and 28 mg·kg−1 for the RC, FA, and GM treatments, respectively. These mineral N concentrations indicated that a portion of applied organic fertilizer N, and N attributable to vetch (GM and RC), remained in the soil at harvest, suggesting the potential for leaching, which should be taken into account in the overall fertilization program. These research findings suggest that effective vetch cover crop management and the application of organic fertilizers can improve yield and quality of organically managed zucchini.

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Evaluating Cover Crop Mulches for No-till Organic Production of Onions

HortScience ◽

10.21273/hortsci.45.1.61 ◽

2010 ◽

Vol 45 (1) ◽

pp. 61-70 ◽

Cited By ~ 11

Author(s):

Emily R. Vollmer ◽

Nancy Creamer ◽

Chris Reberg-Horton ◽

Greg Hoyt

Keyword(s):

Soybean Meal ◽

Cover Crops ◽

Cover Crop ◽

N Uptake ◽

Organic Production ◽

Weed Suppression ◽

Soil Mineral N ◽

Soil Mineral ◽

Mineral N ◽

No Till

Cover crops of foxtail millet ‘German Strain R’ [Setaria italica (L.) Beauv.] and cowpea ‘Iron & Clay’ [Vigna unguiculata (L.) Walp.] were grown as monocrops (MIL, COW) and mixtures and compared with a bare ground control (BG) for weed suppression and nitrogen (N) contribution when followed by organically managed no-till bulb onion (Allium cepa L.) production. Experiments in 2006–2007 and 2007–2008 were each conducted on first-year transitional land. Mixtures consisted of cowpea with high, middle, and low seeding rates of millet (MIX-70, MIX-50, MIX-30). During onion production, each cover crop treatment had three N rate subplots (0, 105, and 210 kg N/ha) of surface-applied soybean meal [Glycine max (L.) Merrill]. Cover crop treatments COW and BG had the greatest total marketable onion yield both years. Where supplemental baled millet was applied in 2006–2007, onion mortality was over 50% in MIL and MIX and was attributed to the thickness of the millet mulch. Nitrogen rates of 105 and 210 kg N/ha increased soil mineral N (NO3– and NH4+) on BG plots 2 weeks after surface application of soybean meal each year, but stopped having an effect on soil mineral N by February or March. Split applications of soybean meal could be an important improvement in N management to better meet increased demand for N uptake during bulb initiation and growth in the spring.

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Early nitrogen supply as an alternative management for a cover crop-maize sequence under a no-till system

Nutrient Cycling in Agroecosystems ◽

10.1007/s10705-021-10158-1 ◽

2021 ◽

Author(s):

Letusa Momesso ◽

Carlos A. C. Crusciol ◽

Rogério P. Soratto ◽

Carlos A. C. Nascimento ◽

Ciro A. Rosolem ◽

...

Keyword(s):

Conventional Method ◽

Cover Crops ◽

Cover Crop ◽

Crop Residues ◽

N Fertilizer ◽

Mineral N ◽

N Application ◽

N Release ◽

Maize Grain ◽

Biomass Decomposition

AbstractOptimizing agronomic efficiency (AE) of nitrogen (N) fertilizer use by crops and enhancing crop yields are challenges for tropical no-tillage systems since maintaining crop residues on the soil surface alters the nutrient supply to the system. Cover crops receiving N fertilizer can provide superior biomass, N cycling to the soil and plant residue mineralization. The aims of this study were to (i) investigate N application on forage cover crops or cover crop residues as a substitute for N sidedressing (conventional method) for maize and (ii) investigate the supply of mineral N in the soil and the rates of biomass decomposition and N release. The treatments comprised two species, i.e., palisade grass [Urochloa brizantha (Hochst. Ex A. Rich.) R.D. Webster] and ruzigrass [Urochloa ruziziensis (R. Germ. and C.M. Evrard) Crins], and four N applications: (i) control (no N application), (ii) on live cover crops 35 days before maize seeding (35 DBS), (iii) on cover crop residues 1 DBS, and (iv) conventional method (N sidedressing of maize). The maximum rates of biomass decomposition and N release were in palisade grass. The biomass of palisade grass and ruzigrass were 81 and 47% higher in N application at 35 DBS compared with control in ruzigrass (7 Mg ha−1), and N release followed the pattern observed of biomass in palisade and ruzigrass receiving N 35 DBS (249 and 189 kg N ha−1). Mineral N in the soil increased with N application regardless of cover crop species. Maize grain yields and AE were not affected when N was applied on palisade grass 35 DBS or 1 DBS (average 13 Mg ha−1 and 54 kg N kg−1 maize grain yield) compared to conventional method. However, N applied on ruzigrass 35 DBS decreased maize grain yields. Overall, N fertilizer can be applied on palisade grass 35 DBS or its residues 1 DBS as a substitute for conventional sidedressing application for maize.

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Cover Crop for a Sustainable Viticulture: Effects on Soil Properties and Table Grape Production

Agronomy ◽

10.3390/agronomy10091334 ◽

2020 ◽

Vol 10 (9) ◽

pp. 1334 ◽

Cited By ~ 2

Author(s):

Concetta Eliana Gattullo ◽

Giuseppe Natale Mezzapesa ◽

Anna Maria Stellacci ◽

Giuseppe Ferrara ◽

Giuliana Occhiogrosso ◽

...

Keyword(s):

Soil Quality ◽

Cover Crops ◽

Cover Crop ◽

Conventional Tillage ◽

Table Grape ◽

Microbial Biomass C ◽

Yield Reduction ◽

Total N ◽

Organic C ◽

Grape Quality

Cover crops are increasingly adopted in viticulture to enhance soil quality and balance the vegetative and reproductive growth of vines. Nevertheless, this sustainable practice has been only recently used for table grape viticulture, with results often contrasting. The aim of this study was to assess the effect of a fescue (Festucaarundinacea Schreb.) cover crop on soil quality, yield, and grape qualitative parameters in a table grape vineyard (cv “Italia”) located in southern Italy, comparing results with the conventional tillage. Soil organic carbon (C), total nitrogen (N), microbial biomass C (MBC), β-glucosidase (BGLU) and alkaline phosphomonoesterase (APME) activities were assessed during three growing seasons (2012–2014) and three phenological stages. The trend of soil chemical and microbiological properties was jointly influenced by the soil management system, growing season and phenological stage. Compared to conventional tillage, cover crops increased, on average, soil organic C, total N, MBC, BGLU and APME by 136%, 93%, 112%, 100% and 62%, respectively. Slight or no effects of cover crops were observed on grape quality and yield, except for 2012 (the driest season), when a yield reduction occurred. This study reveals that cover crops strongly enhance soil quality in the short-term, with potential advantages for grape production in the long-term.

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Mechanical Termination of Diverse Cover Crop Mixtures for Improved Weed Suppression in Organic Cropping Systems

Weed Science ◽

10.1614/ws-d-12-00066.1 ◽

2013 ◽

Vol 61 (1) ◽

pp. 162-170 ◽

Cited By ~ 30

Author(s):

Sam E. Wortman ◽

Charles A. Francis ◽

Mark A. Bernards ◽

Erin E. Blankenship ◽

John L. Lindquist

Keyword(s):

Weed Control ◽

Cover Crops ◽

Cover Crop ◽

Relative Yield ◽

Residue Management ◽

Yield Reduction ◽

Weed Biomass ◽

Early Season ◽

Species Mixture ◽

Grass Weed

Cover crops can provide many benefits in agroecosystems, including the opportunity for improved weed control. However, the weed suppressive potential of cover crops may depend on the species (or mixture of species) chosen, and the method of cover crop termination and residue management. The objective of this study was to determine the effects of cover crop mixture and mechanical termination method on weed biomass and density, and relative crop yield in an organic cropping system. A field experiment was conducted from 2009 to 2011 near Mead, NE, where spring-sown mixtures of two, four, six, and eight cover crop species were included in a sunflower–soybean–corn crop rotation. Cover crops were planted in late March, terminated in late May using a field disk or sweep plow undercutter, and main crops were planted within 1 wk of termination. Terminating cover crops with the undercutter consistently reduced early-season grass weed biomass, whereas termination with the field disk typically stimulated grass weed biomass relative to a no cover crop control (NC). The effects of cover crop mixture were not evident in 2009, but the combination of the undercutter and the eight-species mixture reduced early-season weed biomass by 48% relative to the NC treatment in 2010. Cover crops provided less weed control in 2011, where only the combination of the undercutter and the two-species mixture reduced weed biomass (by 31%) relative to the NC treatment. Termination with the undercutter resulted in relative yield increases of 16.6 and 22.7% in corn and soybean, respectively. In contrast, termination with the field disk resulted in a relative yield reduction of 13.6% in soybean. The dominant influence of termination method highlights the importance of appropriate cover crop residue management in maximizing potential agronomic benefits associated with cover crops.

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Integration of Cover Crops and Strip-tillage Systems for Vegetable Production

HortScience ◽

10.21273/hortsci.32.3.539f ◽

1997 ◽

Vol 32 (3) ◽

pp. 539F-540

Author(s):

John Luna ◽

Mary Staben ◽

Tim O'Brien

Keyword(s):

Cover Crops ◽

Cover Crop ◽

Biological Diversity ◽

Sweet Corn ◽

Yield Reduction ◽

Corn Yield ◽

Vegetable Production ◽

Tillage Systems ◽

Tillage Practices ◽

Strip Tillage

Five on-farm trials were conducted in the Willamette Valley of western Oregon in 1996 to evaluate the potential for integrating winter-annual cover crops and rotary strip-tillage in vegetable productions systems. Two kinds of rotary strip tillers were used to till strips into killed winter cover crops or wheat stubble. Strip-tillage systems were compared to the “standard tillage” practices of the participating growers. In two sweet corn trials, yield of sweet corn was reduced ≈1 MT/ha in the strip-tillage treatments, compared to the standard tillage practices used by the growers. In these trials, the number of tillage operations was reduced by four to five passes with the strip-tillage system. In two other sweet corn trials, corn yield was reduced by ≈4.5 to 5.6 MT/ha in the strip-till treatments compared to the standard tillage treatments. In a transplanted broccoli trial, the strip-tillage and standard tillage treatments produced comparable yields. Possible factors reducing crop yield in the strip till systems include reduced soil temperature at planting and during early growth, soil moisture depletion in the undisturbed cover crop areas, soil compaction, nitrogen immobilization by the cover crop, weed competition, and possible glyphosate/microbiological interactions. Although an economic analysis of this project has not yet been completed, a rough estimate of tillage costs at $25/40 per pass per ha suggests that, in the field with only a 1 MT/ha yield reduction, the reduction in tillage costs would offset the yield reduction in corn (valued at about $88/MT). If yield reducing factors can be understood and a predictable, manageable system of strip-till vegetable production developed, there is a potential to dramatically reduce tillage costs and enhance soil quality through conservation of soil organic matter and biological diversity.

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Economic Return in Production of Lettuce and Cantaloupe Is Affected by Cropping System and Management Practice

HortScience ◽

10.21273/hortsci.39.6.1319 ◽

2004 ◽

Vol 39 (6) ◽

pp. 1319-1323 ◽

Cited By ~ 2

Author(s):

Edmund J. Ogbuchiekwe ◽

Milton E. McGiffen ◽

Mathieu Ngouajio

Keyword(s):

Cover Crops ◽

Cover Crop ◽

Management Practices ◽

Management Practice ◽

Cropping Systems ◽

Crop Management ◽

Cropping System ◽

Net Return ◽

Net Returns ◽

Integrated Crop Management

Economic analysis compared the returns of cropping systems and management practices for production of fall lettuce (Lactuca sativa L.) and spring cantaloupe (Cucumis melo) following summer cover crops. The cover crop treatments included: cowpea [Vigna unguiculata (L.) Walp.] incorporated into the soil in the fall, cowpea used as mulch in the fall, sorghum sudangrass [Sorghum bicolor (L.) Moench] incorporated into the soil in the fall, and a bare ground control. Lettuce and cantaloupe were managed using conventional, integrated, and organic practices. The effect of each cropping system and management practice on crop yield, cost of production and net return was determined. In 1999 and 2000, yield and net return were greatest for cantaloupe and lettuce when the cowpea cover crop was incorporated into the soil before planting. The effect of crop management practice varied with type of cover crop. When lettuce was planted into cowpea-incorporated treatment in 1999, conventional management had the highest cash return followed by integrated crop management. In 2000, organically-grown lettuce after cowpea incorporated had the highest net return followed by integrated crop management grown under cowpea incorporated treatments. In 1999 and 2000, integrated cantaloupe following cowpea-incorporated treatment had the highest yield and cash-return. A 20% price premium for organic produce increased the net returns for the organic-grown lettuce and cantaloupe. Organic lettuce following cowpea-incorporated treatments produced a high net of $2,516/ha in 1999 and $5,971/ha in 2000. The net returns due to 20% organic premium price varied between 1999 and 2000 in cantaloupe production. They were highest for organic cantaloupe after bareground with a net return of $4,395 in 1999 and $3,148 in 2000 for organic cantaloupe after sudangrass.

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428 PB 165 SPATIAL AND TEMPORAL VARIATION IN ORCHARD SOIL NITROGEN EXTRACTABILITY

HortScience ◽

10.21273/hortsci.29.5.492e ◽

1994 ◽

Vol 29 (5) ◽

pp. 492e-492

Author(s):

Hilary J. Sampson ◽

S. A. Weinbaum

Keyword(s):

Cover Crops ◽

Management Practices ◽

Fertilizer Application ◽

Organic Fertilizers ◽

Spatial And Temporal Variation ◽

Rooting Zone ◽

Land Leveling ◽

Soil Variation ◽

Winter Cover ◽

Winter Cover Crops

Extractable soil N may be leached below the plant rooting zone. and into the ground water. Orchards devoid of actively growing winter cover crops are subject to the greatest risk of NO3- leaching during tree dormancy in California. We examined the patterns of KCl extractable NH4+ and NO3-. and potentially mineralizable N (PMN) in the top 10 cm of soil across transects (60 samples, 150 m) in 3 almond orchard systems at 5 phenological stages in 1993. Extractable N was affected both spatially and temporally by management practices (e.g. herbicide or fertilizer application) and soil temperature. PMN did not exhibit local spatial patterns; geostatistical analysis revealed a trend across the transects indicating a larger scale of soil variation. possibly resulting from land leveling. The conventionally-managed orchard without a cover crop demonstrated higher levels of extractable NH4+ and NO3- in the top 10 cm in Feb. and Nov. 1993, compared with orchards managed with organic fertilizers and winter cover crops.

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