D. Joseph Eakes

Effects of irrigation and nitrogen rates on foliar mineral composition of bell pepper

Abstract Irrigation and nitrogen fertilization are two important aspects of bell pepper production. Yet, limited information is available on the effect of irrigation on foliar nutrient content. Bell pepper were grown on bare ground under two nitrogen fertilization rates (11 and 19 kg N week‐1) and irrigated according to an irrigation scheduling model based on weather data and crop age. Eight irrigation rates ranged between 36 and 148% of the model rate. Leaf samples were taken at first bloom (62 days after transplanting, DAT) and after final harvest (84 DAT). Yield response and the foliar content of all essential elements determined [nitrogen (N), phosphorus (P), potassium (K), calcium (Ca), magnesium (Mg), boron (B), copper (Cu), iron (Fe), molybdenum (Mo), manganese (Mn), zinc (Zn)] responded linearly or quadratically to irrigation rates and most foliar nutrient contents remained within or above the sufficiency range. Foliar mineral content tended to be lower at 84 DAT as compared to 62 DAT. Only Ca bec...

EFFECT OF LIMING MATERIALS ON SOIL AVAILABLE NUTRIENTS, YIELD, AND GRADE DISTRIBUTION OF DOUBLE-CROPPED TOMATO AND CUCUMBER GROWN WITH PLASTICULTURE

For economical reasons, cucumber (Cucumis sativus L.) may be grown as a double crop after tomato (Lycopersicon esculentum Mill.). In this production system, plant nutrition may be limited for the second crop due to pH change or insufficient levels of calcium or magnesium. The objective of this 2-year field study was to compare the effects of selected liming materials on yield and grade distribution, and soil available nutrients of a tomato/cucumber double crop produced with plasticulture. Liming materials were compared to a control and a CaSO4 treatment based on the same neutralizing value as standard agricultural limestone. Supplemental N fertilization was provided by weekly injections at a rate of 7 kg/ha/week from ammonium nitrate (NH4NO3) or calcium nitrate [Ca(NO3)2]. Each year, soil samples were collected at the beginning of the study and after each crop to determine nutrient availability. All liming materials raised soil pH in 1998 and 1999 over the unlimed control, though not to the target level for tomato and cucumber production (pH 6.5). Throughout the study, agricultural limestone, a high CaO-containing blend (calcitic blend) and a CaO/MgO (dolomitic blend), resulted in greater fruit weights compared to the control and CaSO4. These materials, along with quick lime (CaO), provided higher levels of soil Ca and Mg available for plant growth. However, it was found that current recommendations for potassium (K), regardless of liming source, were not adequate for optimal soil reserves and yields in this tomato/cucumber cropping system. Ammonium nitrate as a source of N for fertilization was as effective as Ca(NO3)2.

Effect of nitrogen form ratio on pansy growth and nutrition and the palatability to white‐tailed deer

Abstract Pansies are one of the most popular annual bedding plants in the United States. Growth and uptake of essential nutrients as influenced by N‐form ratio was evaluated in pansy as well as what role pansy nutrition plays in the protection of pansy against feeding damage by white‐tailed deer provided by selected repellents. Plants were grown under three N‐form ratios: 100:0, 50:50, and 0:100NO3:NH4. Dry weight was highest for pansy treated with 100:0 and lowest for plants treated with 0:100 NO3:NH4 Mean quality ratings were 4.07 for pansies grown with 100:0,1.80 for pansies grown with 50:50, and 0.78 for pansies grown with 0:100. Potassium (K), magnesium (Mg), and manganese (Mn) content was lower in plants treated with 0:100 than in those treated with 100:0. Ammonium may have competed with these cations for uptake. Boron (B), copper (Cu), molybdenum (Mo), and aluminum (Al) content was highest in plants treated with N‐NH4. There was no significant difference shown in nutrient levels caused by repellent...

Liming materials and rates for Boston ferns in a soilless medium: I. Effect of pH

Abstract The growth of Nephrolepis exaltata (L.) Schott ‘Compacta’ was compared for plants growing in a peat‐perlite medium limed at three rates using two liming materials, dolomitic limestone and hydrated lime. Greatest fern growth occurred with no lime or low lime treatments. Both liming materials produced rapid changes in pH, which remained relatively consistent for 16 weeks. Two procedures were used to monitor pH; a standard soil testing procedure and effluent analysis. The pH ranges resulting in the greatest growth were 3.8–5.1 for media pH values and 3.6–5.5 for effluent pH values.

A simple format for reporting methods used in nutritional studies : Application with Loropetalum response to fertilizer rates

Abstract Loropetalum (L. chinense) cv ‘Blush’, ‘Burgundy’, and ‘Pizzazz’ were grown for 16 months using different rates and application schedules of a 17–7–12 slow‐release fertilizer. Rates were45,68,or 91 g pot1, each applied once in the Spring, or as a split application, half in the Spring, and half in the Fall. A simple format for reporting fertility, methodology used in tissue sampling, and analytical methodology was developed and used. Fertilizer treatments did not affect significantly growth and color ratings 4 and 12 months after potting (p>0.30). ‘Burgundy’ was significantly the fastest growing cultivar. Yet, all plants from all treatments and cultivars were of commercial quality 12 months after potting. Foliar nutrient content was significantly affected by fertilization treatment for most of the essential elements (p 0.10). However, differences due to fertilizer treatments were of limited practical importance as they did not follow the trends in fertilizer rates. Bas...

EFFECT OF LIMING MATERIALS ON MEDIA pH AND OVERALL GROWTH AND NUTRITION OF DWARF NANDINA

ABSTRACT Ground dolomitic limestone (CaCO3/MgCO3) is used throughout the southeastern United States as a fertilizer amendment to soilless media. In addition to neutralizing media acidity, carbonate-based limestone also provides a source of calcium (Ca) and magnesium (Mg) for growth of many woody ornamental species, among these dwarf nandina. This study was conducted to compare the effects of CaO and CaO/MgO/CaCO3 blends to ground dolomitic limestone on the growth, marketable quality, and foliar nutrition of Nandina domestica ‘Nana Purpurea’ grown in soilless media. Materials were preplant incorporated based on the calcium carbonate equivalence (CCE, or acid-neutralizing equivalence) of ground dolomitic limestone (CCE=63) and plants were arranged in a completely randomized design (CRD). Growth indices (GI) were determined and plants harvested for tissue dry matter weights and foliar nutrient content. Plants amended with CaO, agricultural gypsum (CaSO4ċ2H2O), or pelletized dolomitic limestone, were of similar or better quality than plants amended with ground dolomitic limestone. Greatest nutrient uptake [nitrogen (N), Ca, potassium (K), and phosphorus (P)] was likewise observed for these treatments. All liming materials resulted in higher nutrient uptake compared to the unlimed control and highest foliar Mg was reported for plants amended with ground and pelletized dolomitic limestones. In year 1, plants were of similar quality, with the exception of the Ca(OH)2 treatment, which gave the lowest foliar quality ratings. In year 2, all plants were of marketable quality. Throughout the study, and especially during year 2, many foliar nutrient levels fell below established survey averages for dwarf nandina, illustrating the need to supplement media mixes with additional fertilizers during the growing season. All liming materials raised media pH to within the target range for nursery crops (pH=5.5–6.5) within one month from initial application, but lost their most positive neutralizing effect by the end of the third month. Research conducted indicates that CaO, CaO/MgO/ CaCO3 blends, CaSO4ċ2H2O, or pelletized limestone may serve as suitable alternatives to ground dolomitic limestone for use in soilless media.

'Safety first': A simple and practical safety manual for the analytical laboratory

Abstract The emerging analytical laboratory of the late 1990s is based on the technical, quality assurance/quality (QA/QC) control, and safety manuals. While much emphasis has been placed on analytical techniques and QA/QC programs, laboratory safety should not be addressed only in cases of emergency. However, following safety guidelines may not be simple. In many cases in the United States, Federal or State laws, and city or county ordinances are not clear, or limited in scope. University‐affiliated laboratories can often rely on the office of safety and environmental health for university‐wide safety policies. Because these policies are often difficult to implement and because relying on common sense for laboratory safety is insufficient, we drafted ‘Safety First’, a simple and practical laboratory safety manual. Its objective is to highlight the ‘details’ that make the laboratory a safe and pleasant place to work in. It is not intended to replace any other official safety document. It is primarily inte...