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Kenneth L. Steffen, Michael S. Dann, Jayson K. Harper, Shelby J. Fleischer, Sizwe S. Mkhize, Doyle W. Grenoble', Alan A. MacNab, Ken Fager and Joseph M. Russo

During the initial season of implementation, four tomato production systems differing in soil management, pest control practices, and level of inputs, such as labor, materials, and management intensity were evaluated. These systems were CON, a low input (no mulch, no trellising, overhead irrigation, preplant fertilization, scheduled pest control), conventional agrichemical system; BLD, a high input [straw mulch, trellising, trickle irrigation, compost fertility amendment, integrated pest management (IPM)], ecologically-oriented system that emphasized the building up of soil organic matter levels and used no agrichemicals to supply fertility or for pest control; BLD+, a system similar to BLD, except that agrichemical pesticides were used; and ICM, a high input system (black polyethylene mulch, trellising, trickle irrigation, fertigation, IPM pest control) that used agrichemicals to supply fertility and for pest control. Soil characteristics and fertility levels in the BLD and BLD+ systems were modified with extensive amendments of spent mushroom compost and well-rotted cattle manure. Levels of agrichemical NPK calculated to meet current crop needs were supplied to the CON and ICM systems, with 75% of fertility in the ICM system supplied through the trickle irrigation lines (fertigation). The BLD system had a greater soil water holding capacity and sharply reduced irrigation requirements. During a wet period, fruit cracking and evidence of water-mold root rot were significantly higher in the ICM system than the BLD and CON systems. Defoliation by Alternaria solani was greatest in the BLD system and least in the ICM system. The BLD and ICM systems resulted in a 1 week earlier peak yield compared to the CON system. The yield of No. 1 fruit was 55% to 60% greater in the BLD+ system than the other three systems, which were comparable in yield. Net return was highest in the BLD+ system, although the benefit/cost ratio was greatest in the CON system. This multidisciplinary study has identified important differences in the performance of diverse production systems during the unique transitional season.

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Amaya Atucha and Greg Litus

surface area ( Lehmann, 2007a ; Thies and Rillig, 2009 ). Studies have shown that soil amendments with biochar have improved soil fertility, as a result of an increase in pH of acid soils ( Zwieten et al., 2010 ), or increase in nutrient retention as a

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Joseph C. Fetter, Rebecca N. Brown and José A. Amador

fertilizer, the potential for N mineralization increases ( Zuberer, 2005 ), increasing N availability to the turfgrass. Organic fertilizers thus have the potential to increase soil fertility and SOM content over the long term ( Booze-Daniels and Schmidt, 1997

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Jennifer Moore-Kucera, Anita Nina Azarenko, Lisa Brutcher, Annie Chozinski, David D. Myrold and Russell Ingham

that organic growers are required to “manage crop nutrients and soil fertility through rotations, cover crops, and the application of plant and animal materials” to meet certification requirements [§205.203b ( National Organic Program, 2002 )]. The

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David Conner and Anusuya Rangarajan

consider how costs fit into overall labor, cash flow, weed, pest, fertility, and marketing management strategies. Both farms spent relatively little on pest control sprays (less than 1% of total input costs), relying on soil fertility and other management

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Guangyao Wang, Mathieu Ngouajio and Darryl D. Warncke

crop biomass, soil nutrient levels were generally similar in all treatments, regardless of whether cover crops were used. The lack of difference in soil fertility between the cover crops and the control was likely because weeds were allowed to grow in

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Javier Fernandez-Salvador, Bernadine C. Strik and David R. Bryla

, 2012 )]. The yield response of blackberry to increased rates of N fertilizer has been variable, depending on soil fertility, rates of N fertilizer used, and plant cultivar or age ( Archbold et al., 1989 ; Naraguma and Clark, 1998 ; Nelson and Martin

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Rebecca J. Long, Rebecca N. Brown and José A. Amador

movement of gases and water ( Brady and Weil, 2008 ). Soil fertility. At the 18 May 2013 and 2 June 2014 sampling dates (directly following amendment addition), control plot inorganic N (NO 3 + NH 4 ) levels were significantly higher than most waste

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Joseph R. Heckman, Thomas Morris, J. Thomas Sims, Joseph B. Sieczka, Uta Krogmann, Peter Nitzsche and Richard Ashley

1 Extension Specialist in Soil Fertility. To whom reprint requests should be addressed. E-mail address: . 2 Extension Specialist in Soil Fertility. 3 Professor of Soil and Environmental Chemistry. 4 Associate Professor. 5

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J.L. Walworth, D.E. Carling and G.J. Michaelson

3 Research Associate. 1 Assistant Professor of Soil Fertility/Horticulture. 2 Professor of Horticulture. The authors wish to acknowledge Peter Rissi for his technical assistance with these studies. The cost of publishing this paper was