crop management in the orchard with root/rhizosphere-based nutrient management. Enhancing nutrient-use efficiency through optimizing fertilizer input, improving fertilizer formulation, and maximizing biological interaction effects helps develop healthy
Xin Zhao, Qianqian Dong, Shubang Ni, Xiyong He, Hai Yue, Liang Tao, Yanli Nie, Caixian Tang, Fusuo Zhang, and Jianbo Shen
Craig D. Stanley and Gurpal Toor
that is used sets the potential for subsequent water and nutrient use efficiency. Although all irrigation system methods differ in degree of efficiency of application ( Smajstrla et al., 2002a ), improper design or operation of any system can further
Youssef Rouphael, Giampaolo Raimondi, Rosanna Caputo, and Stefania De Pascale
semiclosed soilless culture. Water use efficiency. The WUE ET was not significantly affected by the nutrient management strategy with an average value of 1.84 kg·m −3 ( Fig. 2 ). On the contrary, significant difference between the two nutrient management
Michelle Hadawi-Broeske and Helen C. Harrison
Renewed interest in soil conservation over the past decade has led to greater research efforts in the area of living mulch cropping systems. However, crop/mulch competition continues to present challenges. The objective of this study was to determine what effect two types of chemical growth suppressants (Mycogen 6121—an herbicidal soap, and Royal Slo-grow—a soil plant growth regulator) had on the water-use efficiency, nutrient use, and soil-shading ability of two annual living mulches, ryegrass (Lolium multiflorum) and crimson clover (Trifolium incarnatum). Two greenhouse experiments were performed in sand culture using a modified Hoagland's soap, one rate of growth regulator, and a mechanical treatment of mowing. Significant differences in nutrient use and soil-shading ability were obtained. The second experiment (69 days) replicated the ryegrass treatments less one rate of soap and included the legume crimson clover with one rate of soap and one rate of growth regulator. Results from both experiments will be discussed.
Martin P.N. Gent and Richard J. McAvoy
and nutrient use efficiencies under PSEFW were in addition to those resulting from the ebb and flow itself ( Kent and Reed, 1996 ; Purvis et al., 2000 ). The increased water and nutrient use efficiency will result in the use of less fertilizer and
Mary Ann Rose
Timing nutrient application to periods of high nutrient demand could increase nutrient use efficiency and reduce the potential for fertilizer leaching or runoff. However, current recommendations for field nursery and landscape ornamentals (extension publications) suggest fertilizing in late fall and early spring despite research with perennial fruit crops that demonstrates low uptake potential during those times. Research is needed to resolve this apparent conflict. Application rates for woody ornamentals, established in the 1960s and 1970s, also need reexamination in the light of environmental concerns.
John M. Dole, Janet C. Cole, and Sharon L. von Broembsen
`Gutbier V-14 Glory' poinsettias (Euphorbia pulcherrima Willd. Ex. Klotzsch) grown with ebb-and-flow irrigation used the least amount of water and produced the least runoff, and plants grown with capillary mats used the greatest amount of water and produced the most runoff, compared to microtube and hand-watering systems. The maximum amount of water retained by the pots and media was greatest for the microtube and ebb-and-flow systems and became progressively lower for the hand-watering and capillary mat systems. The media and leachate electrical conductivity from plants grown with subirrigation systems was higher than those grown with top irrigation. For the two top-irrigation systems (microtube and hand-watering), plants grown with 250 mg N/liter from a 20N-4.4P-16.6K water-soluble fertilizer had greater leaf, stem, and total dry weights than those grown with 175 mg N/liter. The two subirrigation systems (ebb-and-flow and capillary mat) produced plants that were taller and had greater leaf, stem, and total dry weights when grown with 175 than with 250 mg N/liter. The higher fertilizer concentration led to increased N, P, Fe, and Mn concentration in the foliage. Nitrogen concentration was higher in top-irrigated plants than in subirrigated plants. The ebb-and-flow system produced the greatest total dry weight per liter of water applied and per liter of runoff; capillary mat watering was the least efficient in regard to water applied and runoff.
Alison A. Stoven, Hannah M. Mathers, and Daniel K. Struve
Department of Agriculture. Species used in this study: Acer xfreemanii `Jeffersred' (Autumn Blaze® maple), Cercis canadensis L. (Eastern redbud), Malus `Prairifire' (Prairifire crabapple), Quercus rubra L. (Northern red oak)
Carolyn F. Scagel, Guihong Bi, Leslie H. Fuchigami, and Richard P. Regan
nutrients available from the growing substrate and fertilizer. The influence of N availability on nutrient uptake efficiency and allocation of biomass and nutrients to each structure was assessed by analysis of variance using a complete factorial design with
Pedro García-Caparrós, Alfonso Llanderal, and María Teresa Lao
beginning of the experiment gave an average of 75 mg N, 9 mg P, and 3 mg K per plant. These values of nutrient uptake were then used to calculate nutrient uptakes efficiencies (percentages that reflect the fraction of applied nutrient accumulated by plant