ABSTRACT
Plants play an ever-increasing role in providing safe and healthy food for a growing world population, and in replacing the limited and expensive fossil resources as feedstock for the production of energy and industrial materials toward environmental protection. The transition to a sustainable economy is based largely on the renewable biological resources-the “knowledge-based bioeconomy,” which is inevitable and desirable. The strategic agenda for plant research outlines an approach that can contribute toward addressing major socioeconomic challenges: (a) To fulll the consumerdemandforsafe,sustainable,andhealthyfood.Novelplantsaimatdeliveringnonallergic foods and foods with longer shelf lives, better nutritional composition, and more varied tastes. (b) To increase the agricultural productivity while decreasing its environmental footprint. Novel plants may need fewer inputs in terms of water, fertilizer, or pesticides and will be more stress resistant, for instance, against drought or seasonal instabilities that are caused by climate change. (c) To exploit the potential of biomass for the production of industrial materials. Plants (crops and trees)
24.1 Introduction .......................................................................................................................... 595 24.2Classication of Metal Ions according to Their Toxicity ..................................................... 596 24.3Effect of Toxic Metals on Photosynthetic Electron Transport ............................................. 596
24.3.1Copper....................................................................................................................... 597 24.3.2Mercury .................................................................................................................... 601 24.3.3 Organometallic Compounds .....................................................................................603 24.3.4Cadmium ..................................................................................................................603 24.3.5Nickel ........................................................................................................................605 24.3.6Lead ..........................................................................................................................605 24.3.7Chromium .................................................................................................................605 24.3.8 Zinc ...........................................................................................................................606 24.3.9Iron ............................................................................................................................606
