Search Results

You are looking at 1 - 10 of 6,656 items for :

Clear All

Release rates at 21 °C were determined in sand columns for 12 commercially available soluble and controlled-release Mg fertilizers. Lutz Mg spikes, K2SO4, MgSO4, MgSO4·H2O, and MgSO4·7H2O released their Mg within 2 to 3 weeks. Within the first 6 weeks, MgO·MgSO4 released its soluble Mg fraction, but little release occurred thereafter. Dolomite and MgO released <5% of their Mg over 2 years while MagAmp released <20% of its Mg. Florikan 1N-0P-26K-4Mg types 100 and 180 exhibited typical controlled-release fertilizer characteristics, with most of their Mg release occurring during the first 15 weeks.

Full access

as the high source thresholds per nutrient trait by Codex Alimentarius (1997) definitions: 4.2 mg/100 g Fe, 90 mg/100 g Mg, 300 mg/100 g Ca, and 4.5 mg/100 g Zn, by fresh weight basis. Previous studies have evaluated vegetable amaranth for nutrition

Free access

Abstract

An Mg-N formulation (RES-20482) used as a 0.25 or 0.50% spray solution or when trunk injected at 5 ml/2.54 cm of trunk circumference did not significantly increase leaf Mg of pecan (Carya illinoensis (Wang.) K. Koch).

Open Access

fruit samples, N was determined by combustion on a 0.12–0.13 g sample using a Leco-FP-528 N-analyzer (LECO Corporation, St. Joseph, MI). Ca, Mg, B, P, and K were determined by inductively coupled argon plasma spectrophotometry (Spectro Analytical

Free access

Abstract

Magnesium sulfate applied as a soil amendment (34 kg Mg/ha annually for 3 years or a single application of 224 kg Mg/ha) increased leaf Mg 5 years after initial application. Dolomite increased soil pH and soil test Mg but not leaf Mg. Sulfate of potash magnesia and MgO increased soil test Mg and slightly, though insignificantly, increased leaf Mg. Single foliar sprays of MgSO4 and Mg(NO3)2 did not affect leaf Mg.

Open Access

Abstract

Where Mg deficient ‘Washington’ navel orange trees were sprayed with Mg, leaf Mg was increased from a deficient to an optimum level in the first year of application. However, it was not until the fourth year of application that a yield increase occurred. At least 2 sprays annually were required. There was an increase in total soluble solids in the juice as a result of the sprays, but there were no other consistent effects on fruit quality. Magnesium in the feeder roots was increased by the foliage sprays. Leaf K was decreased by the Mg sprays. One year after cessation of the sprays the leaf Mg was again in the deficiency range.

Open Access

Abstract

A method was developed to determine the total Ca, Mg, and K content of apple (Malus domestica Borkh.) pulp based on an assay in the water-extractable fraction. Water-soluble and total levels of each of the three elements in the fruit correlated significantly (P < 0.001) at harvest. The method is accurate (cv = 4.1%, 4.1%, and 2.5% for Ca, Mg, and K, respectively) and time-saving. The total level of minerals determined by the method proposed correlated well (P < 0.001) with that obtained by acid digestion of freeze-dried apple pulp.

Open Access

Abstract

Analysis of deficiency symptoms and foliar analyses of canopy leaves (youngest leaves 5 cm of wider) of Rieger elatior begonias (Begonia X hiemalis Fotsch cv. Schwabenland Red) indicated that the minimum critical levels for K, Mg, and B lie in the ranges of 0.93 to 0.95%, 0.22 to 0.25%, and 13.0 to 14.0 ppm, respectively.

Open Access
Author:

Abstract

In sand culture studies, oxidized N (NO3-N) sources increased Ca and Mg and decreased Fe and Mn leaf concentrations in ‘Cheyenne’ blackberry (Rubus spp. L.). Leaf concentrations of K increased, and P, Mg, and Ca decreased with increased K fertilization. High Ca fertilization increased Ca in the leaves but did not affect leaf concentration of other elements measured. Increasing Mg fertilization decreased N and increased Mg leaf concentrations. After two growing seasons, high Mg and Ca fertilization increased, whereas high K decreased plant growth. Significant interactions indicated synergistic and/or antagonistic influences of K and Mg fertilization treatments on the Ca elemental leaf concentrations.

Open Access

Abstract

Unimbibed seeds of cabbage (Brassica oleracea L. Capitata group, cv. Early Jersey Wakefield, were artificially aged at 40°C in 100% relative humidity for up to 20 days. Aged seed and non-aged seed were imbibed in H20 at 25° in the dark up 0, 1, 4 or 16 hours, after which concentrations of Ca, Mg, Mn, K, and Cl in the whole seed were determined by neutron activation analysis. Concentrations of Ca, Mg, and Mn did not significantly change during the imbibition period for either control or aged seed. However, as the aging time increased, seeds lost increasing amounts of K and Cl during imbibition. The concentration of K decreased continually throughout the imbibition period in both aged seed and control seed. The decrease was significantly greater in the aged seed. Cl, too, was lost during imbibition and like K, the greater loss occurred in aged seed.

Open Access