The Distribution of some Inorganic Elements in Plant Tissue 2

Tomato plants were fed with calcium 45, cobalt 60, copper 64, iron 59, magnesium 28, manganese 54, molybdenum 99, potassium 42, sodium 24, tungsten 187, and zinc 65 in sand or water culture. Fresh tissues were then extracted with a series of reagents, and the percentage radioactivity determined in each fraction. Apart from calcium and iron, a measurable proportion of the assimilated activities were found in a form soluble in ethanol: the nature of the soluble cobalt and zinc complexes was investigated. Almost all the elements were removed by treatment with dilute hydrochloric and perchloric acids, but significant amounts of iron and cobalt were left in the residue.