The history of agricultural science is a sub-field of the history of agriculture which looks at the scientific advancement of techniques and understanding of agriculture. Scientific study of fertilizer was advanced significantly in 1840 with the publication Die organische Chemie in ihrer Anwendung auf Agrikulturchemie und Physiologie (Organic Chemistry in Its Applications to Agriculture and Physiology) by Justus von Liebig. One of Liebig's advances in agricultural science was the discovery of nitrogen as an essential plant nutrient.
Johann Friedrich Mayer was the first scientist to publish experiments on the use of gypsum as a fertilizer, but the mechanism that made it function as a fertilizer was contested by his contemporaries.
In 1840, Liebig published what is now known as Liebig's law of the minimum. Liebig's law states that growth is not controlled by the total amount of resources available, but by the limiting factor.
In the United States, a scientific revolution in agriculture began with the Hatch Act of 1887, which used the term "agricultural science". The Hatch Act was driven by farmers' interest in knowing the constituents of early artificial fertilizer. Later on, the Smith-Hughes Act of 1917 shifted agricultural education back to its vocational roots, but the scientific foundation had been built. After 1906, public expenditures on agricultural research in the US exceeded private expenditures for the next 44 years.
A genetic study of Agricultural science began with Gregor Mendel's work. Using statistical methods, Mendel developed the model of Mendelian inheritance which accurately described the inheritance of dominant and recessive genes. His results were controversial at the time and were not widely accepted.
In 1900, Hugo de Vries published his findings after rediscovering Mendel's work, and in 1905 William Bateson coined the term "genetics" in a letter to Adam Sedgwick. The study of genetics carried into an experiment isolating DNA.
Agronomy and the related disciplines of agricultural science today are very different from what they were before about 1950. Intensification of agriculture since the 1960s in developed and developing countries, often referred to as the Green Revolution, was closely tied to progress made in selecting and improving crops and animals for high productivity, as well as to developing additional inputs such as artificial fertilizers and phytosanitary products.
However, environmental damage due to intensive agriculture, industrial development, and population growth have raised many questions among agronomists and have led to the development and emergence of new fields (e.g., integrated pest management, waste treatment technologies, landscape architecture, genomics).
New technologies, such as biotechnology and computer science (for data processing and storage), and technological advances have made it possible to develop new research fields, including genetic engineering, improved statistical analysis, and precision farming.
There are various universities around the United States which are well known for educating students in the field of the agricultural sciences. These universities include Texas A&M, Stephen F. Austin State University, University of Idaho and many others.