Conclusions and Perspectives
The achievements of the book are wrapped up regarding gain in basic knowledge, spin-off to practice and potential for theory development. Complexity in plant response required the integration of transitions between empirically acquired evidence and theory-based modelling, and between validity for case studies towards universality as additional spatio-temporal dimensions in process scaling. This enabled evidential conflicts to be resolved on mechanistic and ecologically relevant grounds. Plants possess “opportunities” beyond costs of trade-offs in resource allocation, with response plasticity as an intrinsic biological principle that requires “system biology” to holistically extend beyond molecular analysis. Biotic interactions were drivers of whole-plant allocation. Advances foster plant breeding and engineering as well as resource-efficient stand management in agriculture and forestry. “Growth–differentiation balance theory” progressed in terms of mechanistic and ecological differentiation, accounting for dynamics and multi-functionalities in regulatory capacity and adopting a “holobiontic view” on biotic interactions involved in plant resource allocation.