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Janet C. Cole and John M. Dole

These studies were conducted to determine the effect of 1) temperature on P leaching from a soilless medium amended with various P fertilizers, 2) water application volume on P leaching, and 3) various fertilizers on P leaching during production and growth of marigolds (Tagetes erecta L. `Hero Flame'). Increasing temperature linearly decreased leaching fraction; however, total P leached from the single (SSP) or triple (TSP) superphosphate-amended medium did not differ regardless of temperature. Despite a smaller leaching fraction at higher temperatures and no change in the total P leached, P was probably leached more readily at higher temperatures. More P was leached from the medium amended with uncoated monoammonium phosphate (UCP) than from the medium containing polymer-coated monoammonium phosphate (CTP) at all temperatures, and more P was leached from UCP-amended medium at lower temperatures than at higher temperatures. More P was leached from TSP- than from SSP-amended medium and from UCP- than from CTP-amended medium regardless of the water volume applied, but leachate P content increased linearly as water application volume increased for all fertilizers tested. Plant dry weights did not differ regardless of P source. Leachate electrical conductivity (EC) was lower with TSP than with SSP. Leachate EC was also lower with CTP than with UCP. A higher percentage of P from controlled release fertilizer was taken up by plants rather than being leached from the medium compared to P from uncoated fertilizers.

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Andrew G. Ristvey, John D. Lea-Cox, and David S. Ross

hypothesize that current N and P application rates to many ornamental species in container production exceed normal plant N and P growth requirements resulting in low uptake efficiencies and excessive nutrient loss through leaching. A review by Chen et al

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Tyler C. Hoskins, James S. Owen Jr., and Alex X. Niemiera

Maximizing nutrient use efficiency and minimizing leaching and non-point source contributions through runoff have been persistent challenges in containerized crop production that drive both researchers and growers to develop new technologies and

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Aaron Heinrich, Richard Smith, and Michael Cahn

regions in California (the Salinas Valley and Tulare Basin) found that 51% of all N applied to cropland is leached to groundwater ( Harter and Lund, 2012 ). As a result, many wells in these areas exceed the U.S. Environmental Protection Agency (EPA

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Juan Carlos Díaz-Pérez and Touria E. Eaton

United States, eggplant is often produced with high levels of irrigation water (above the rate of ETc) and N fertilizer, resulting in water waste and N leaching. Excessive irrigation rate not only wastes water, but may also result in reduced yields in

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Cody J. Stewart, S. Christopher Marble, Brian Jackson, Brian J. Pearson, P. Christopher Wilson, and Dwight K. Lauer

100:0, 80:20, and 60:40 and found that although water holding capacity increased with increasing peatmoss percentage, there was no effect on creeping woodsorrel germination. Leaching of herbicides in different growing substrates has also been

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Amanda Bayer, John Ruter, and Marc W. van Iersel

fertilizer out of concern that lower fertilizer applications could negatively impact growth ( Owen et al., 2008 ; Tyler et al., 1996 ). The combination of excessive irrigation and high fertilizer rates often leads to significant leaching of fertilizers

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Lea Corkidi, Donald J. Merhaut, Edith B. Allen, James Downer, Jeff Bohn, and Mike Evans

leaching ( Juntunen et al., 2002 ; Million et al., 2007 ). A number of Best Management Practices have been proposed to maximize production and minimize water contamination from runoff and leaching losses. These practices vary with particular nursery

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G. J. Keever and J. S. Jacobson

Abstract

Greenhouse-grown plants of Zinnia elegans Jacq. were exposed to simulated sulfuric acid rain 30 minutes per day twice a week for 6 weeks at pH 2.8, 4.0, and 5.6. Injury occurred primarily to older, mature leaves and cotyledons at pH 2.8 and 4.0 and to ray flowers at pH 2.8. Plants supplied with higher levels of Hoagland’s nutrient solution grew more rapidly, contained greater quantitities of foliar K, P, and Ca, and exhibited more foliar injury after exposure to acidic simulated rain (SR). Dry weight of plants given full-strength nutrient solution (highest level) was depressed at pH 2.8 and increased at pH 4.0 relative to pH 5.6. Loss of 86Rb by leaching from foliage was significantly increased at pH 2.8, but no differences in total foliar content of K, P, and Ca were detected.

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Tim R. Pannkuk, Jacqueline A. Aitkenhead-Peterson, Kurt Steinke, James C. Thomas, David R. Chalmers, and Richard H. White

Excessive losses of nitrogen (N), orthophosphate (P), and DOC from soil by leaching is indicative of breaks in their respective nutrient cycles. Losses of these nutrients are typically caused by management practices or natural disturbances in the