show very obvious symptoms of nutrient deficiencies. The different growth stages of these plants require different nutrients. The plants that are forty to seventy days old are considered young. This stage of the young plants is called the vegetative growth stage. This means they have not begun flowering and producing their fruit. In this stage, most of the increase in mass occurs in the leaves. When the tomato plants are at harvest, most of the plant’s mass comes from the fruit that it produces. These plants require high amounts of nutrients. One of the most important nutrients that they require is phosphorus. (Wilcox, 1994)

Nitrogen must be fixed into an inorganic compound in order for it to be useable by plants, therefore, nitrogen is commonly the most deficient element in soils. According to Bergmann (1992), around one to five percent of a plant’s weight comes from nitrogen (Bergmann, 1992, p. 86). The most common effect that a plant experiences during nitrogen deficiency is stunted growth. This occurs because nitrogen plays a huge part in proteins and nucleic acids. It also plays a role in many macromolecules. The yellowing of a plant’s older leaves is another known effect of nitrogen deficiency. This color change occurs because, in order for chlorophyll formation to occur, nitrogen must be present (Salisbury and Ross, 1992, p. 130; Bennett, 1994). When the nitrogen is not present, the newer leaves withdraw the nutrients from its older tissues since nitrogen is a mobile element.

Nitrogen deficiency can also impede vegetative growth and quicken flowering. The reasoning behind this is that this deficiency places many hormonal effects within the plant. These effects cause a change in cytokinin and abscisic acid synthesis. It causes the synthesis of abscisic acid to accelerate while slowing the synthesis of cytokinin, therefore, aging the plant more quickly. This increase in the speed of aging causes the lifespan of the plant to become reduced (Bergmann, 1992, p. 88). Overall, tomato plants with a deficiency