Application Of K2SO4 Research Articles

Recovery of K2SO4 by Alfalfa After Placement at Different Depths in a Low Fertility Soil1

AbstractKnowledge of the quantitative contribution of plant nutrients from the soil volume penetrated by crop roots is needed for an overall analysis of present methods of fertilization. An experiment was initiated in 1971 to determine the uptake of K and SO4 by alfalfa (Medicago sativa L.) from different depths in a low K Plano silt loam soil profile. An injection method was used to place a solution of K2SO4 at depths of 7.5, 22.5, 37.5, 52.5, 67.5, and 82.5 cm below the soil surface in a 2‐year‐old stand. A check and surface broadcast application of K2SO4 also were included as treatments. Potassium sulfate was applied at the rate of 224 kg/ha of K and 92 kg/ha of S. Treatment areas were 8350 cm2. Three cuttings of the entire treatment area were made at first flower during the 1971 season, and the herbage was analyzed for yield and concentrations of K and S.Alfalfa recovered 41, 29, 19, 16, 10, 15, and 11% of the added K from the surface, 7.5, 22.5, 37.5, 52.5, 67.5, and 82.5 cm soil depths, respectively. No major differences were observed in S concentration of the tissue between the check and treatments.These data show that alfalfa absorbed K most heavily from the surface soil area as compared to the Ap and deeper horizons.

Response of Young Lemon Trees to Potassium and Zinc Application — Yield and Fruit Quality1

Abstract Yield of young lemon trees increased with either soil application of K2SO4 or foliage application of KNO3 in an orchard where leaf K was low. Leaf Zn was low but one annual foliage spray of ZnSO4 (control in this study) supplied adequate Zn and there was no response to additional Zn sprays. Peel thickness decreased, and percent juice and percent acid in the juice increased with added K.

Aggregate Effects of Nutrients and Gibberellic Acid on ‘Valencia’ Orange Crop Value1

Abstract In a 5-year factorial fertilizer experiment, an increase in leaf N from 2.54 to 2.71% by soil applications of urea, reduced creasing and fruit size and increased green color on the fruit at harvest. Leaf K was increased from 0.47 to 0.67% by soil application of K2SO4 and to 0.65% by foliar application of KNO3; except for degree of fruit color and leaf N content, effects of soil- and foliar-applied K differed little and both increased yield, fruit size, and green color on the fruit and reduced creasing. Increasing leaf P from 0.132 to 0.139% had little influence on factors influencing the value of the fresh-fruit crop. Gibberellic acid (GA) sprays increased green color on the fruit and reduced creasing. The effects of N, K, and GA on reducing creasing and increasing green color on the fruit were strongly additive. There was an inverse relation between creasing and green color of fruit. Each problem can be reduced but at the expense of the other, and both problems cannot be reduced simultaneously. Packinghouse statements showed that monetary returns/tree were increased about 75% by K treatments without GA; 17% with GA alone; 61% with GA + soil-applied K; and 42% with GA + foliar-applied K.

The effect of calcium carbonate and potassium sulphate on the efficiency of ammonium as tested by barley seedlings

Using the Neubauer technique and the slope ratio, it was found that efficiency of (NH4)2SO4 in the presence of 12.5 or 25.0 g CaCO3 per pot relative to its efficiency without CaCO3 was 0.6 and 0.47, respectively. Application of 4 or 6 mg K/pot, the efficiency of (NH4)2SO4 was 0.56 and 0.33, respectively, relative, to its efficiency without K application. The Dean's ‘a’ value was found to vary with percent CaCO3 or K2SO4 application.

Pertes d'azote par volatilisation ammoniacale après fertilisation en forêt de pin gris

In a field study, percentage of nitrogen lost as ammonia from a jack pine (Pinusbanksiana Lamb.) soil increased with increasing rates of urea application between 112 and 448 kg N/ha. After 7 days, losses amounted to 18–28% of a 224 kg urea-N/ha application, representing 60–87% of the total losses measured over a 6-week period. Maximum volatilization rates occurred between the third and the fifth day after fertilization, at which time urea hydrolysis was virtually complete. Negligible ammonia losses were measured in plots treated with ammonium sulfate, ammonium nitrate, and sulfur-coated urea. Applying superphosphate with urea markedly depressed ammonia volatilization, an effect which was enhanced by a joint application of K2SO4•MgSO4. Reduction of volatilization by artificial precipitation was significant and increased with increasing precipitation when the latter was applied soon after fertilization; decreases in volatilization were then related to the amount of residual urea subject to diffusion into the humus layer or to leaching towards the underlying soil horizons.

The Effect of Chloride and Lime on the Manganese Uptake by Bush Beans and Sweet Corn

AbstractThe effect of chloride and lime on the uptake of Manganese by bush beans (Phaseolus vulgaris) and sweet corn (Zea mays var. rugosa) was investigated under field and greenhouse conditions. Lime and Cl treatments were applied in factorial combinations in both field and greenhouse experimens. Lime was applied at rates up to 3 tons/acre with Cl applied at rates up to 90 lb/acre. All treatments received blanket applications of N, P, and S.The Mn content in the trifoliate bean leaves was high enough to explain the toxicity symptoms observed. At the zero lime rate all applications of chloride resulted in Mn levels > 1,000 ppm. Increasing levels of Cl increased the level of Mn in all cases. The level of Mn at the zero Cl treatment and with added lime was below suggested toxic levels. The application of lime always reduced the Mn content.The application of KCl increased the Mn content of the sweet corn plants, whereas the application of K2SO4 or K2CO3 had no effect on the Mn content.

The effect of soil reaction on the growth of young citrus plants. II.

Further studies of the effect of soil pH on the growth of young Unshu orange trees were attempted, applying two forms each of nitrogenous and potassium fertilizers.1. The favorable soil pH for the growth of trees based on shoot length, and total fresh and dry weights was 6.23-7.25 in the case of NH4-N and KCl, and 623-7.18 in the case of NH4-N and K2SO4. However, when NO3-N was applied, the growth was nearly the same in most of the plots except the plot of strongly acid soil (nearly pH 4), regardless of the soil pH and the form of potassium fertilizer.2. Total amounts of N, P2O5 and K2O contained in a tree increased as its growth became greater. MgO was however absorbed more abundantly in various plots of NO3-N than in corresponding plots of NH4-N. With lowering soil pH, the total amount of CaO decreased, while that of Mn increased evidently, independently of the growth. The absorption of N and P2O5 in plots of NH4-N was much promoted by an application of K2SO4 than that of KCl.3. A significantly positive correlation existed between the isoelectric point of root tissues, and their buffer capacity became greater with lowering soil pH.