Grand challenges in plant physiology: the underpinning of translational research.

A grand challenge, it would seem, has to be grand, i.e., large and impressive in size, scope, or extent. While each plant physiologist would likely come up with a list of challenges in their own area of work, to be truly grand these should span the entire discipline of plant physiology, and ideally have significant impact on both science and technology. The question then is what is the scope of “plant physiology?” Turns out there are numerous definitions in use. This journal considers it to encompass the “nature of functioning of an organism” studied at various levels of complexity and embracing the full range of technologies from cell biology to systems biology. Likewise, the journal with this name considers it to include broad aspects of plant biology, including an “understanding of the plant as a whole organism and its interactions with symbionts, pathogens and pests, and the environment,” and employing disciplines ranging from cell and molecular biology, biochemistry, and biophysics to genetics and physiology (Chrispeels and Raikhel, 2000). These are consonant with my definition of plant physiology, which I consider to be generally synonymous with plant science and plant biology. Thus, I see “physiology” as a relevant component of most if not all of the Frontiers specialties listed on the journal website1 and believe it would be difficult to come up with a definition of plant physiology that excluded these areas. However, in the challenges discussed in this article I will try to minimize the overlap with the challenges elaborated in other Specialities. A corollary to this is that future authors should recognize that articles destined for the Frontiers in Plant Science series could fit under several Specialities, and they are free to decide where their work would fit best. In my view, the truly grand challenges in plant physiology are those that will yield important insights about how plants live and function, and also provide at least partial solutions to critical societal needs. Some of the most pressing needs are contained in the recent A New Biology report from the National Research Council (NRC, 2009), which outlined sustainable food production, ecosystem restoration, biofuel production, and human health as four major societal needs – grand challenges indeed. These same challenges show up in the areas targeted by the recently created National Institute for Food and Agriculture (NIFA) that has focused competitive research programs around the themes of climate change; bioenergy; food safety; nutrition and childhood obesity; and global food security. Similarly, the recently formed Global Plant Council has identified world hunger, energy, climate change, health and well-being, sustainability and environmental protection as major challenges that need to be addressed on a broad scale2. Thus, I would submit that the grand challenge is to determine how plant physiology research can be applied to help solve these major societal needs, which will likely involve integrated multi-disciplinary approaches with physiology playing an important role. So how can plant physiology research help achieve the grand challenge? Taking a fairly restrictive view of what constitutes physiology research, we might consider each of the three traditional areas of physiology research: (i) metabolism (including nutrition); (ii) growth and development (vegetative and reproductive); and (iii) response to the environment. Each of these is an area of active work where breakthroughs could result in progress toward societal needs, and a partial list (and admittedly biased) of specific challenges and opportunities is highlighted below.