Plant Physiology as Sachs Found It

Abstract

Julius von Sachs, in whose honor this celebration is held, began his work at a strategic time in the development of plant physiology. The foundational sciences of chemistry and physics had emerged from the restraints imposed upon them by the spirit of the Middle Ages and the bases for many of the modern concepts had been laid. Since the development of modern plant physiology was necessarily dependent upon a scientific understanding of the laws of physics and chemistry the best that could be expected of primitive biological studies was an accurate description of the apparent reactions of organisms. Although the ancients, including the most noted of the philosophers, had a modicum of essentially correct concepts of animal physiology, because of the subjective element in human physiology they failed, due to the objective character of plants, in understanding even as much concerning them as they knew of animals. The nutritional dependence of plants upon their environment, together with a realization that some method of transfer of materials in the plant is necessary, the obvious importance of seeds in the continuity of life and certain empirical observations upon apparent values of certain fertilizing materials-these constituted essentially the stock in trade of the ancients. Later, analogies between the better-known activities of animals, especially of the human body, and the supposed reactions of plants resulted in the accumulation of certain hypotheses which, although unsupported by experiments or adequate observation, have in some instances more recently been demonstrated as correct. These, however, were scarcely more than lucky guesses. It is true, nevertheless, that progress in animal physiology has often been of great value in suggesting profitable lines of investigation