Cover crops support arthropod predator activity with variable effects on crop damage during transition to organic management

It has been shown that soil management under organic farming can enhance soil organic carbon, thereby mitigating atmospheric greenhouse gas increases, but until now quantitative evaluations based on long term experiments are scarce, especially under Mediterranean conditions. Changes in soil organic carbon (SOC) content were examined in response to organic management with cover crops in a Mediterranean citrus plantation using 21 years of survey data. Soil organic carbon increase was more apparent 5 years after a land management change suggesting that, for citrus plantations on Mediterranean conditions, studies should be longer than five years in duration. Soil organic carbon sequestration rate did not significantly change during the 21 years of observation, with values ranging from -1.10 Mg C ha-1 y-1 to 1.89 Mg C ha-1 y-1. After 21 years, 61 Mg CO2 ha-1 were sequestered in long-lived soil C pools. These findings demonstrate that organic management is an effective strategy to restore or increase SOC content in Mediterranean citrus systems.

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Increasing Sustainability by Intercropping

HortTechnology ◽

10.21273/horttech.3.3.309 ◽

1993 ◽

Vol 3 (3) ◽

pp. 309-312 ◽

Cited By ~ 19

Author(s):

R.M. Coolman ◽

G.D. Hoyt

Keyword(s):

Cover Crops ◽

Cover Crop ◽

Crop Production ◽

Effective Means ◽

Crop Damage ◽

N Fixation ◽

Plant Interactions ◽

Biological N Fixation ◽

System A ◽

Mutual Advantage

Plant interactions are both competitive and cooperative. Farmers use intercropping to the mutual advantage of both main and secondary crops in a multiple-crop-production system. A vegetable crop has a competitive advantage over a younger secondary cover crop interseeded before vegetable maturity. Non-legume intercropped cover crops can use soil N, while a legume intercrop can increase N in agricultural systems by biological N fixation. Intercropping also may be more efficient than monocropping in exploiting limited resources. Relay-planting main crop and intercrop components so that resource demands (nutrients, water, sunlight, etc.) occur during different periods of the growing season can be an effective means of minimizing interspecific competition. Intercropping systems often exhibit less crop damage associated with insect and plant pathogen attacks, and they provide weed control.

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

HortScience ◽

10.21273/hortsci.46.8.1154 ◽

2011 ◽

Vol 46 (8) ◽

pp. 1154-1162 ◽

Cited By ~ 11

Author(s):

Joji Muramoto ◽

Richard F. Smith ◽

Carol Shennan ◽

Karen M. Klonsky ◽

James Leap ◽

...

Keyword(s):

Cover Crops ◽

Cover Crop ◽

Fertilizer Application ◽

Economic Benefits ◽

Organic Fertilizers ◽

Yield Reduction ◽

Mineral N ◽

N Content ◽

Organic Management ◽

Net Return

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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Soil macrofauna in cover crops of figs grown under organic management

Scientia Agricola ◽

10.1590/s0103-90162005000100011 ◽

2005 ◽

Vol 62 (1) ◽

pp. 57-61 ◽

Cited By ~ 12

Author(s):

Analy de Oliveira Merlim ◽

José Guilherme Marinho Guerra ◽

Rodrigo Modesto Junqueira ◽

Adriana Maria de Aquino

Keyword(s):

Cover Crops ◽

Cover Crop ◽

Soil Fauna ◽

Soil Depth ◽

Paspalum Notatum ◽

Living Mulch ◽

Soil Macrofauna ◽

Organic Management ◽

Nutrient Mineralization ◽

Macroptilium Atropurpureum

Soil fauna plays an important role in organic management through their effects on soil organic decomposition, nutrient mineralization, and amelioration of the soil's physical properties. This work evaluates the density and diversity of the soil macrofauna under types of cover plants in areas cultivated with Ficus carica L. under organic management. The soil macrofauna was collected in 0.25 × 0.25 m areas, down to a soil depth of 0.3 m, and at the surface layer. The treatments consisted of bahiagrass living mulch (Paspalum notatum), siratro living mulch (Macroptilium atropurpureum), and bahiagrass mulch. The highest macrofauna density and the lowest diversity were observed in bahiagrass, of which 80% were represented by ants, thus characterizing the soil under this cover crop as showing the lowest functional diversity and quality.

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Cover crops

AccessScience ◽

10.1036/1097-8542.165900 ◽

2015 ◽

Keyword(s):

Cover Crops

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Sugarcane Weevil Borer (Rhabdoscelus Obscurus) in Fiji Islands and Recommendations Towards Its Control

Outlooks on Pest Management ◽

10.1564/v30_dec_07 ◽

2019 ◽

Vol 30 (6) ◽

pp. 261-266

Author(s):

Danian Singh ◽

Lionel Joseph ◽

Zafiar Naaz ◽

Kelera Railoa

Keyword(s):

Papua New Guinea ◽

Current Method ◽

Crop Damage ◽

Agricultural Export ◽

Fiji Islands ◽

The World ◽

Raw Sugar ◽

Viable Method ◽

Sugarcane Weevil ◽

Sugarcane Industry

Pests have been a constant threat to agriculture the world over. In the Fiji Islands where the major agricultural export commodity is raw sugar, the Sugarcane weevil borer is one such agricultural pest that poses a real threat to an already ailing industry. The Sugarcane weevil borer (Rhabdoscelus obscure) is a pest originally found in Papua New Guinea whose introduction into Fiji has resulted in crop damage particularly to the soft variety of sugarcane found in Fiji. This review highlights the emergence of the weevil borer and explains a possible control that could be implemented by the Fijian farmers. The current method of control in Fiji uses the split billet trap. While this method has been recognized as an economically viable method of controlling the spread of the weevil borer, it has not been completely effective in eradicating the pest. This paper highlights and puts forth recommendations on other methods which could be used by the sugarcane industry.

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New Technologies to Combat Herbicide Resistance

Outlooks on Pest Management ◽

10.1564/v30_apr_09 ◽

2020 ◽

Vol 31 (2) ◽

pp. 90-92

Author(s):

Rob Edwards

Keyword(s):

Winter Wheat ◽

Herbicide Resistance ◽

Cover Crops ◽

New Technologies ◽

Green Revolution ◽

Arable Land ◽

Limited Range ◽

Cultural Control ◽

Arable Farming ◽

The Uk

Herbicide resistance in problem weeds is now a major threat to global food production, being particularly widespread in wild grasses affecting cereal crops. In the UK, black-grass (Alopecurus myosuroides) holds the title of number one agronomic problem in winter wheat, with the loss of production associated with herbicide resistance now estimated to cost the farming sector at least £0.5 billion p.a. Black-grass presents us with many of the characteristic traits of a problem weed; being highly competitive, genetically diverse and obligately out-crossing, with a growth habit that matches winter wheat. With the UK’s limited arable crop rotations and the reliance on the repeated use of a very limited range of selective herbicides we have been continuously performing a classic Darwinian selection for resistance traits in weeds that possess great genetic diversity and plasticity in their growth habits. The result has been inevitable; the steady rise of herbicide resistance across the UK, which now affects over 2.1 million hectares of some of our best arable land. Once the resistance genie is out of the bottle, it has proven difficult to prevent its establishment and spread. With the selective herbicide option being no longer effective, the options are to revert to cultural control; changing rotations and cover crops, manual rogueing of weeds, deep ploughing and chemical mulching with total herbicides such as glyphosate. While new precision weeding technologies are being developed, their cost and scalability in arable farming remains unproven. As an agricultural scientist who has spent a working lifetime researching selective weed control, we seem to be giving up on a technology that has been a foundation stone of the green revolution. For me it begs the question, are we really unable to use modern chemical and biological technology to counter resistance? I would argue the answer to that question is most patently no; solutions are around the corner if we choose to develop them.

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Evaluation of Ryegrass Cover Crops in Rearing Ponds for Florida Largemouth Bass

The Progressive Fish-Culturist ◽

10.1577/1548-8640(1984)46<55:eorcci>2.0.co;2 ◽

1984 ◽

Vol 46 (1) ◽

pp. 55-57 ◽

Cited By ~ 1

Author(s):

C. W. Bowling ◽

W. P. Rutledge ◽

J. G. Geiger

Keyword(s):

Cover Crops ◽

Largemouth Bass

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