The differential effect of the ions of three-salt solutions on the growth of potato plants sand culture

Abstract

A great deal of work has been carried out, mainly by American plant physiologists, on the effect of mixtures of three or more salts in varying· proportions on the growth of plants in culture solution. In Tottingham’s original work (1) a mixture of four salts was employed, consisting of seven ions; later the system was reduced by Shive to six ions. The plant employed in both cases was a variety of barley. In 1924 E. S. Johnston (2) published a paper on “Growth of Potato Plants in Sand Cultures” treated with the “six types” of nutrient solutions. In this work the six ions employed by Shive (3) were used, but they were utilised as combinations in varying proportions of the six possible molecular groupings giving six types of solution. As each series was in duplicate, a large body of data is available for a further analysis of the differential effects of the individual ions. In common with previous workers, Johnston was content to select, merely by inspection, the particular culture solutions which appeared to give the greatest yields.