Centenary of"Researches on irritability of plants"by Jagadis Chandra Bose

In 1913 Sir Jagadis Chandra Bose published a monograph (see the coverpage in fig.1) “Researches on irritability of plants”’ [1]. The concept of irritability [2] had its origin in the works of Francis Glisson and Albrecht von Haller [3]. On the basis of experiments performed on animals, Haller emphasised the distinction between ‘sensibility’ and ‘irritability’the ability to perceive a stimulus is sensibility whereas the ability to respond to that stimulus is called irritability. For example, nerves are the vehicles of sensibility whereas muscle contraction is one mode of irritability. Till the end of the nineteenth century, the experimental investigations of irritability were carried out, almost exclusively, with animals. Sir J.C. Bose was one the few visionaries who did the pioneering works on the irritability of plants with a very sophisticated equipment that he himself developed for this purpose. In this commemorative article I briefly discuss the aims of the investigations reported in this classic and the impact of the results. I also mention how irritability depends on the operation of molecular machines, a concept pioneered by Marcello Malpghi [4] in the sixteenth century and a subject of current mutidisciplinary research in the twentieth century [5, 6].