Effects of Application of Thiamine to Cosmos

Abstract

Earlier expts. of Bonner and Greene (Bot. Gaz., 101: 401-500, 1939) on the application of thiamine to nutrient soln. supplied to Cosmos plants were repeated. Such applications appeared to elicit increases in dry wt. of plant produced under the conditions used. The growth of Cosmos was found to be increased over that obtained in the earlier experiments by use of higher greenhouse temps. Plants grown at a controlled constant temp. of 68[degree]F appeared to respond to application of thiamine, plants grown at a constant controlled temp. of 80[degree]F, or at a day temp. of 80[degree] combined with a night temp. of 68[degree] failed to show any response to thiamine application.