Photosynthesis at Low Temperatures

One of the most variable conditions in the field is temperature and relatively severe frost, caused by temperatures below -20°C, can be expected to occur over 42% of the earth’s surface (Larcher 1995). Low temperature is therefore a major determinant of the geographical distribution and productivity of plant species. Exacerbating this problem, plants from high latitudes and high altitudes are faced with short growing seasons and the need to grow at low temperatures for prolonged periods to extend the growing season. Thus, the capacity for active photosynthesis during prolonged exposure to low growth temperatures is essential in determining their successful site occupancy and subsequent productivity. Despite the importance of low temperatures in determining agricultural productivity and ecological diversity at higher latitudes and altitudes, relatively little is known about either the short-term or long-term effects of cold on the underlying biochemical responses of plant energy metabolism, processes that contribute to plant growth.