Calorimetry as an analytical tool for germination tests of plant seeds

Heat evolution associated with the germination of radish seeds was quantitatively studied in a calorimeter. After incubation at 30 degrees C for 20 to 50 h, the total heat evolved was correlated with the length of buds and roots, and with the increase in weight of the germinating seeds. By regression analysis, the heat produced per unit of bud and root growth was found to be a1 = 0.5723 J/mm of bud and a2 = 0.7093 J/mm of root, respectively, with a correlation coefficient of 0.9577. From these results we conclude that the calorimetric determination of the heat generated during germination is a valid reflection of the germination activity of radish seeds. Our calorimetric method is applicable to the quantitative investigation of the viable activity of plant seeds.