The growth–differentiation balance hypothesis states that there is a physiological trade-off between growth and secondary metabolism. Cella Pizarro and Bisigato (pp. 297–307) investigate the response of six species subjected to differing water supply in terms of biomass and resource allocation. They find that drought affects growth-related processes rather than defence-related secondary metabolism or allocation, thus suggesting there may be limitations to the general applicability of the hypothesis.
