Form Of Fertilizer Research Articles

Phosphorus‐micronutrient interaction effects on crop production

Abstract Detrimental effects of P interactions with micronutrients on plant growth and nutrition have been reported frequently in the past 20 years. Despite the frequency of such reports, much remains to be learned about the specific mode of action of such interactions and consequent development of control measures. Specific examples of P‐micronutrient interactions include P‐Zn, P‐Fe, P‐Cu, P‐Mn, P‐Mo, and P‐B couples. Generally, interactions of the metals with P in plant nutrition have been expressed as an intensification of micronutrient deficiency when supplemental P was used when micronutrients were deficient or near‐deficient. Intensification of the micronutrient deficiency has been accompanied by a decline in the concentration and uptake of the particular element in the plant. On the other hand, P has been demonstrated to improve uptake of Mn, Mo and B. Explanations of various P‐micronutrient interactions have centered on translocation relationships, metabolic interferences, soil reactions, and depressed concentrations due to dilution effects. Varietal differences have been demonstrated in several species including corn, sorghum, soybeans, and dry beans. Soil pH has also been associated with such interactions largely through relationships of pH to micronutrient availability. In addition to physiological or soil relationships, P‐micronutrient interactions also can occur in fertilizer formulations at or prior to time of application. These interactions may result in the formation of less soluble reaction products, lowering the availability of both the micronutrient and the applied P. Some improvement in micronutrient availability has also been suggested to result from the inclusion of a particular metal in polyphos‐phate‐containing fertilizers. Recent research in P‐micronutrient interactions is summarized including both physiological, soil and fertilizer formulation aspects. Recommendations for future areas of research along with efficient use of P and micronutrients are included.

Transformation of ammonium and nitrate fertilisers in two soils of low and high nitrification activity

Abstract Transformations of (NH4)2SO4 and Ca(NO3)2 applied to a soiI of low (Wharekohe silt loam) and a soil of high (Waimate North clay loam) nitrification activity were studied using both unlabelled and 15N-labelled fertilisers. The problems associated with both techniques are briefly discussed. Total recovery of applied N in soil and plant estimated from 15N recovery, was similar for both forms offertiliser 84 days after application (about 65%) to Waimate North clay loam, but was superior for (NH4)2SO4 (70%) relative to Ca(NO3)2 (33%) on Wharekohe silt loam. Isotopic dilution occurred in the A horizon, decreasing the 15Nenrichment in the mineral N pool and leading to an underestimation of the effect of fertiliser N on N uptake by pasture.

Spray Chrysanthemum Production with Controlled-release Fertilizer and Trickle Irrigation1

Abstract Various rates, types, and formulations of controlled-release fertilizers were evaluated as potential components in a trickle irrigation production system for spray chrysanthemums (Chrysanthemum morifolium Ramat.). Optimum rates of total-N, with 34 kg N/ha as soluble 6-2.6-5 (N-P-K) and the remainder as 14-6.1-11.6 Osmocote, were estimated to be from 489-501 kg per planted hectare in 2 tests. Other formulations or ratios of Osmocote and urea formaldehyde fertilizers at similar rates did not improve production or were not comparable to Osmocote 14-6.1-11.6 or to the commercial practice of weekly overhead liquid fertilization. A water savings of 70-80% was estimated with the controlled-release fertilizer-trickle irrigation system compared to overhead irrigation, while yields (marketable stems and height) were similar to those produced with overhead-liquid fertilization practices.

The influence of placement geometry on the effectiveness of copper superphosphate

In a glasshouse experiment wheat plants were grown for 45 days at various distances from granules of copper superphosphate. Only plants growing within 2 cm of the fertilizer granules were able to utilize the copper. This result is interpreted as indicating that close contact between plant roots and fertilizer is necessary for optimum copper utilization. Methods of fertilizer formulation and application should be designed to promote close contact.

Chemical and Biochemical Considerations for Maximizing the Efficiency of Fertilizer Nitrogen

AbstractFertilizer nitrogen is subject to loss from the soil‐root zone, and immobilization by the soil and rhizosphere microfloras, which can result in low recovery and use efficiency of the applied nitrogen. With increasing rates of application, fertilizer nitrogen efficiency decreases progressively, while leaving an increasing amount of unused nitrogen as a potential pollution hazard. Since the point of greatest economic return from this nutrient is usually somewhere below the point of maximum yield, it should be possible to adjust fertilizer nitrogen rates for maximum return and minimum loss to the environment. This can be achieved through improved soil and crop management practices, including proper timing of application of conventional nitrogen fertilizers and use of deep‐rooted crops for recovery of leached nitrate. A rational approach to more meaningful nitrogen recommendations is needed, one which would account for residual fertilizer nitrogen and mineralizable soil nitrogen, and allow an accurate prediction of the amount of supplemental fertilizer nitrogen necessary to produce the desired yield. Efficiency of fertilizer nitrogen might also be increased with controlled release fertilizers, including the use of coated granules, and compounds of limited water solubility blended with conventional nitrogen fertilizers, to achieve a specific release rate coincident with the nitrogen requirements of a crop. Formulation of ammoniacal fertilizers with nitrification inhibitors offers considerable opportunity for increasing fertilizer nitrogen efficiency.

INJURIOUS EFFECTS OF FERTILIZERS APPLIED WITH THE SEED ON THE EMERGENCE OF FLAX

Several fertilizer formulations were placed with the seed of Rocket flax at various rates to observe their effects on emergence.In field tests, 20 pounds of nitrogen per acre placed with the seed significantly reduced emergence. When broadcast, 80 pounds caused no reduction in stand, and yields were increased. Whenever the fertilizer treatments reduced the stand of flax to 43 plants per foot of row or less, yields were reduced. This number of plants corresponds to a seeding rate of approximately 36 pounds per acre.In greenhouse tests it was generally safe to apply up to 15 pounds of nitrogen with flax seed if soil moisture was adequate. P2O5 in the form of mono-ammonium phosphate could be safely applied at rates from 5 to 20 pounds, depending on the N:P2O5 analysis of the fertilizer. The greater the amount of N in the fertilizer, the less P2O5 could be used. Results with mono-calcium phosphate were more erratic and generally less satisfactory than with mono-ammonium phosphate. The former could not be used safely at rates above 15 pounds P2O5 per acre.Damage to flax from commercial fertilizers was greater when the moisture content of the soil was low. The results indicated that fertilizers at normal rates should not be applied in close contact with flax seed unless there is adequate moisture for germination and growth.

Effects of Fertilizer Applications on Two Generations of Slash Pine

AbstractA series of 37 plots was established on which three formulations of fertilizer were applied at five rates to two age‐classes of slash pine growing in Florida. The fertilizer caused increases in the nutrient contents of needles and branches of the younger trees and of cones and seeds in the older trees. Basal‐area growth was increased as much as 32% in the older trees. Fertilizer treatments had no significant effect on cone length but produced heavier seeds. When these seeds were germinated in the greenhouse, they produced larger more vigorous seedlings with higher contents of nitrogen, phosphorus and potassium than did seeds produced on control trees.

Fertilizer Calculations, Granular Fertilizer Formulation with the IBM 702 Computer

Fertilizer Calculations, Granular Fertilizer Formulation with the IBM 702 Computer

Fertilizer Formulation, Simplified Approach to Calculations for Formulating High-Analysis, Mixed Fertilizers

Fertilizer Formulation, Simplified Approach to Calculations for Formulating High-Analysis, Mixed Fertilizers

Fertilizer Formulation, Influence of Formulation on Physical Properties of Fertilizers

Fertilizer Formulation, Influence of Formulation on Physical Properties of Fertilizers