DNA and the Environment

In the previous chapter (Chap. ), the potential for genetically modified (transgenic) plants to help feed the planet and provide nutrition was discussed. But how can DNA biology and technology contribute to a sustainable environment more generally? The themes I wanted to discuss are based on the importance of advances in DNA sequencing and analysis in understanding the biosphere and the progress in engineering nitrogen fixation and carbon capture by plants. The first part of the chapter examines the understanding of the soil microbiome that has come from new-generation DNA sequencing techniques. The soil ecosystem drives the plant ecosystem it supports. Similarly in the oceans, the microbiome drives the marine ecosystem. Nitrogen as part of our proteins and DNA is essential for life. Excess nitrogen fertilization and the energy required for nitrogen fertilizer production have become an environmental problem. Work is progressing in engineering nitrogen fixation in major crop plants, based on the understanding of the genetics of the rhizobium–legume symbiosis. Plants have an important role in combating climate change given their capacity for CO2 fixation and their role in maintaining atmospheric homeostasis. Understanding the mechanisms of CO2 fixation is enabling strategies to genetically enhance CO2 capture. Reduced fertilizer use and reduced atmospheric carbon are now realistic propositions.