Application of alpha naphthalene acetamide and alpha naphthalene acetic acid to the stems of bean seedlings affected the total amount and distribution of carbohydrate and nitrogenous compounds in various portions of the plants, and also in the plant as a whole. Some of the chemical responses were specifically associated with the application of the acetamide while another type of chemical response resulted when the plants were treated with the acid. In general the chemical responses were closely associated with growth responses, growth by expansion of leaves and extension of internodes being inhibited in that portion of the plants above the treated section of the stem, while meristematic or cambial activity was stimulated in the treated section and hypocotyls. 2. Tumors, made up largely of meristematic cells, developed in that portion of stems to which naphthalene acetic acid was applied. Analysis of this portion of the stems showed them to contain a relatively high percentage of nitrogen, which was present in the form of compounds that were water-soluble. Increased cambial activity and a relatively large amount of secondary thickening resulted in the treated region of stems following the application of naphthalene acetamide. This portion of the stems contained only slightly more nitrogen than comparable sections of stems of control plants, and a relatively small percentage of the nitrogen present was in the form of water-soluble compounds. 3. Plants treated with naphthalene acetic acid, and also those treated with naphthalene acetamide, contained a lower percentage of starch, dextrin, and sugar in the roots, hypocotyls, and first internodes than did controls. The presence of a limited amount of readily available carbohydrate in these parts of treated plants was associated with the development of a relatively small amount of leaf surface. There was also inhibited transport of carbohydrate from the leaves. Growth responses in the stems were characterized by intensive cambial and meristematic activity, and the initiation of roots within the hypocotyls. Carbohydrate metabolism and transport was so affected as finally to result in a deficiency in the amount of carbohydrate available in those portions of the plants where growth was stimulated for a period following treatment. 4. There was no evidence of nitrogen deficiency, as the percentage of nitrogen present in all portions of plants treated with the acid- and also those treated with the acetamide-was equal to or greater than that in control plants.
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John W. Mitchell (1940) studied this question.