Explain the theory of Law of Minimum   

This is one of the earliest hypotheses put forward by von Liebig on the relationship between the amount of plant  nutrient in the soil and the growth of the plant. The growth of the plant is directly related to the yield. This law is based on the fact that if a soil contains optimum/ adequate amounts of all but one nutrient element, crop growth is regulated by that si ngle nutrient. This means that the crop growth can be varied by varying the amount of that single nutrient. This law is valid upto the stage at which growth starts decreasing .