Mineral Deficiency and Organic Constituents in Tobacco Plants. II. Amino Acids

Abstract

Mineral deficiency affects the amino acid composition of Nicotiana tabacum var. Connecticut Broadleaf. An earlier withdrawal of certain elements during the plant growth period resulted in more severe symptoms and more changes in amino acid composition than later withdrawal. Less differences were observed in the amino acid content of the hydrolyzate fraction among mineral deficient and control plants where deficiencies occurred at earlier stages of growth. Deficiency of B, Ca, P, K, Mg, and S caused an increase in free amino acid content but not so in N deficient plants. Ca and B deficiency appeared to have more effect than others. Mg had a prominent effect only on free amino acid content. In each plant of deficiency treatment, the content of asparagine appeared to show a positive relation to the alkaloid content in that plant. A similar but not so prominent relation between proline and alkaloid content was indicated also.