Historical Information


  Historical Information
  Phosphorus Functions in Plants
  Nature and Transformations of Soil Phosphorus
Diagnosing Phosphorus Deficiency
  Visual Symptoms of Deficiency and Excess
  Tissue Testing for Phosphorus
  Soil Testing for Phosphorus
Factors Affecting Management of Phosphorus Fertilization
  Crop Response to Phosphorus
  Soil Water
  Soil Temperature
  Sources of Phosphorus
  Timing of Application of Phosphorus Fertilizers
  Placement of Phosphorus Fertilizers
  Foliar-Applied Phosphorus Fertilization
  Fertilization in Irrigation Water

Incidental phosphorus fertilization in the form of manures, plant and animal biomass, and other natural materials, such as bones, probably has been practiced since agriculture began. Although specific nutritional benefits were unknown, Arthur Young in the Annuals of Agriculture in the midnineteenth century describes experiments evaluating a wide range of products including poultry dung, gunpowder, charcoal, ashes, and various salts. The results showed positive crop responses to certain materials. Benefiting from recent developments in chemistry by Antoine Lavoisier (1743-1794) and others, Theodore de Saussure (1767-1845) was perhaps the first to advance the concept that plants absorb specific mineral elements from the soil. The science of plant nutrition advanced considerably in the nineteenth century owing to contributions by Carl Sprengel (1787-1859), A.F. Wiegmann (1771-1853), Jean-Baptiste Boussingault (1802-1887), and Justus von Liebig (1803-1873). Based on the ubiquitous presence of phosphorus in soil and plant materials, and crop responses to phosphorus-containing products, it became apparent that phosphorus was essential for plant growth.

Liebig observed that dissolving bones in sulfuric acid enhanced phosphorus availability to plants. Familiar with Liebig's work, John Lawes in collaboration with others, evaluated several apatite-containing products as phosphorus nutritional sources for plants. Lawes performed these experiments in what ultimately became the world's most famous agricultural experiment station-his estate in Rothamsted. The limited supply of bones prompted developments in the utilization of rock phosphates where Lawes obtained the first patent concerning the utilization of acid-treated rock phosphate in 1842, The first commercial production of rock phosphate began in Suffolk, England, in 1847. Mining phosphate in the United States began in 1867. Thus began the phosphorus fertilizer industry. Crop responses to phosphorus fertilization were widespread. For many years phosphorus fertilization practices were based on grower experience often augmented with empirical data from experiment station field tests. Although researchers and growers realized that customized phosphorus fertilizer recommendations would be invaluable, early work often focused on total element content of soils and produced disappointing results. The productivity of soil essentially showed no correlation to total content of nutrients in them.

It was during the twentieth century that the recognition that the plant itself was an excellent indicator of nutrient deficiency coupled with considerable advances in analytical methodology gave way to significant advances in the use of tissue testing. Hall (1) proposed plant analysis as a means of determining the normal nutrient contents of plants. Macy (2) proposed the basic theory that there was a critical concentration of nutrient in a plant above which there was luxury consumption and below which there was poverty adjustment, which was proportional to the deficiency until a minimum percentage was reached.

Also during the twentieth century, a greater understanding of soil chemistry of phosphorus and the observation that dilute acids seem to correlate to plant-available phosphorus in the soil gave way to the development of successful soil-testing methodologies. The early contributions of Dyer (3), Truog (4), Morgon (5), and Bray and Kutrz (6) are noteworthy. Plant tissue testing and soil testing for phosphorus are discussed in greater detail in the subsequent sections. For more detailed history on plant nutrition and soil–plant relationships, readers are referred to Kitchen (7) and Russell (8).