ABSTRACT
This chapter presents an idea that is important to keep in mind when trying to understand the response of plants to stress and, in fact, to any problem in biology. It is most important that biologists be aware of the limits of our knowledge. During development, plants pass through a succession of physiological phases, such as germination, vegetative growth, flowering and fruiting, seed ripening, senescence, and dormancy, which is often referred to as phasic development. The study of the effects of auxins, cytokinins, or both on in vitro cultured cells, by Skoog and Miller, shows the synergistic effect of these phytohormones on cell development and differentiation. The chapter concludes with at least some plants have the capacity to modify their genome under stress, thereby yielding new varieties having high yield under conditions usually considered to be stressful. It also presents an overview of the key concepts discussed in this book.
