This study compared conventional tillage (CT), strip tillage (ST), and no tillage (NT) cultures for effects on tomato (Lycopersicon esculentum) fruit production. Within each tillage system, fertilization treatments were 60 lb/acre (67.2 kg·ha-1) of nitrogen (N) applied as potassium nitrate in four ways: a 2-ft-wide (0.6 m) strip over the row before transplanting, a 4-ft-wide (1.2-m) strip over the row before transplanting, N banded 6 inches (0.15 m) to the side and 4 inches (0.10 m) below the plant after transplanting, or applied through the drip irrigation system. A treatment of no fertilizer was included in the 1996 study but was discontinued in 1998 and 1999 because yields were low and this would not be a recommended practice in Tennessee. Tillage treatments had no effect on early small, medium, or large tomato yields. In 2 of the 3 years, either ST or CT treatments resulted in the highest total yields. Highest early yields were often produced by applying N in either 2-ft or 4-ft, strips over the row before transplanting. Highest late-season yields were obtained from plants receiving N applied as a band beside the row after transplanting. Results suggest that tomato yield under minimal tillage (ST or NT) was at least equivalent to CT in most years. When the economic benefits of minimal tillage are considered, these results imply that minimal tillage cultural practices are advantageous in tomato production.
Jim E. Wyatt, Don D. Tyler, Craig H. Canaday and Don D. Howard
Javier Fernandez-Salvador, Bernadine C. Strik and David R. Bryla
The impact of organic fertilizer source on the growth, fruit quality, and yield of blackberry (Rubus L. subgenus Rubus Watson) cultivars (Marion and Black Diamond) grown in a machine-harvested, organic production system for the processed market was evaluated from 2011 to 2013. The planting was established in Spring 2010 using approved practices for organic production and was certified in 2012. Plants were irrigated using a dripline under a woven polyethylene groundcover (weed mat) installed for weed management. Two sources of liquid fertilizer were evaluated: 1) a corn steep liquor and fish waste digestion blend (“corn”; 2.5N–1.1P–1.2K); and 2) a fish solubles and molasses blend (“fish”; 4N–0P–1.7K). Fertilizers were applied by fertigation through the drip system at rates of 56 kg·ha−1 nitrogen (N) per year in 2011–12 and 90 kg·ha−1 N in 2013. The impact of fertigation on drip system performance was evaluated with two maintenance options, “flushing” and “no flushing” of the driplines. Total yield differed among years, whereas fruit soluble solids concentration and firmness as well as floricane biomass at pruning showed a year × cultivar interaction. ‘Black Diamond’ had greater total yield and average fruit weight than ‘Marion’, but produced a greater proportion unmarketable fruit. There was no effect of fertilizer source on yield, fruit quality, primocane length, or primocanes/plant in any year with the exception of fruit weight, which was greater with corn than with fish. ‘Marion’ had a greater floricane biomass when fertilized with fish than with corn. Soil nutrients were within the recommended range, except for boron (B), which was below recommended levels. Only soil nitrate-N was affected by fertilizer source, which was greater in ‘Marion’ than in ‘Black Diamond’ when fertilized with fish. Primocane leaf tissue nutrient concentrations were within recommended levels for all nutrients, except for calcium (Ca) and B, which were below recommended standards in both cultivars. Primocane leaf potassium (K) and zinc (Zn) concentrations were greater with fish than with corn. There was no fertilizer source or maintenance effect on emitter flow rate of the drip system in either year. However, flow rates decreased an average of 4.5% in the first year and 19% in the second year. Overall, there were no differences between the fertilizers on plant growth, yield, or fruit quality, and both fertilizers were suitable for planting establishment.
Mark E. Lancaster, Jeanine M. Davis and D.C. Sanders
Small-scale research plots and demonstrations of fertilizer application through a drip-irrigation system have inherent characteristics that make using commercial fertilizer injection systems difficult. Uniform fertilizer application, without excessive water, is essential for meaningful results in these small-scale, rate-specific studies. An inexpensive, easy to build, continuously diluting fertilizer injector is described. This injection system was reliable and provided uniform application under the confines of a low flow rate.
T.K. Hartz and G.J. Hochmuth
Drip irrigation provides an efficient method of fertilizer delivery virtually free of cultural constraints that characterize other production systems. Achieving maximum fertigation efficiency requires knowledge of crop nutrient requirements, soil nutrient supply, fertilizer injection technology, irrigation scheduling, and crop and soil monitoring techniques. If properly managed, fertigation through drip irrigation lines can reduce overall fertilizer application rates and minimize adverse environmental impact of vegetable production.
Kelly T. Morgan, Lincoln Zotarelli and Michael D. Dukes
Florida is the most important center of processed citrus (Citrus spp.) production in the United States, and all of the crop is irrigated. Irrigation systems include low-volume microirrigation, sprinkler systems, and subsurface irrigation. This review details the relative irrigation efficiencies and factors affecting irrigation uniformity such as design and maintenance. A wide range of soil moisture sensors (e.g., tensiometers, granular matrix, and capacitance) are currently being used for citrus in the state. The use of these sensors and crop evapotranspiration estimation using weather information from the Florida Automated Weather Network in irrigation scheduling are discussed. Current examples of scheduling tools and automated control systems being used on selected fruit crops in Florida are provided. Research data on the effect of irrigation scheduling, soluble fertilizer injection, and soil nutrient movement, particularly nitrate and the use of reclaimed water in Florida, are also reviewed. Concluding this review is a discussion of the potential for adoption of irrigation scheduling and control systems for citrus by Florida growers and future research priorities.
J.G. Williamson and E.P. Miller
applications per season beginning 1 March and ending 1 Oct.), or as liquid fertilizer via fertigation (every 2 weeks, 16 applications beginning 1 March and ending 15 Oct.). Fertilizer injections were made using a peristaltic pump (MasterFlex LS ® ; Cole
Chris Wilson, Joseph Albano, Miguel Mozdzen and Catherine Riiska
events was estimated from the irrigation volume applied and the fertilizer injection rate. Based on these methods, a total of 4.8, 2.9, 2.5, and 7.3 kg NO 3 -N was applied during the FPN-1, FPN-2, FPN-3, and FPN-4 events, respectively, and 17.1 and 37.1 g
treatments through the irrigation system in a 16N–0P–0K–20Zn liquid solution at a volume of 4.7 L·ha −1 to deliver 1.12 kg Zn/ha. Application dates were 8 May 2013 and 25 Apr. 2014. Trees were irrigated for ≈1 h following fertilizer injections to flush
Luz M. Reyes, Douglas C. Sanders and Wayne G. Buhler
fumigation because of the rapid buildup of microorganisms shortly after fumigation and before the start of fertilizer injections (J. Wargo, unpublished data) The objective of this study was to compare the effectiveness of two formulations of slow
Robert R. Tripepi, Mary W. George, K. Amanda Linskey, John E. Lloyd and Jennifer L. Van Wagoner
foliar N, Mg, Ca, S, and B both years, but foliar Mn was affected by these treatments only in 2003 ( Table 3 ). Trees receiving the compost:bark mixture, fertilizer injection, or fertilizer spike had similar levels of foliar N by the end of the 2002