ABSTRACT
When man started cultivation of crop plants to meet food demands marks the dawn of agriculture. The exact time is not known, but certainly, it was several thousand years before the birth of Christ. Until then, man hunted almost exclusively for food and was nomadic in habits (Tisdale and Nelson, 1966). In the early days, several scientists, especially from Europe, contributed signicantly to the development of agriculture science or mineral nutrition of plants. However, the most signicant contribution came from Justus von Liebig (1803-1873), a German chemist, who very effectively deposed the humus myth. Liebig also emphasized the importance of inorganic plant nutrients as cycling between the living nature and the inorganic nature, mediated by plants. Hence, the contributions that Liebig made to the advancement of agriculture were monumental, and Liebig is perhaps quite rightly recognized as the father of agricultural chemistry (Tisdale and Nelson, 1966).
