Impact of rising tropospheric ozone on potato: effects on photosynthesis, growth, productivity and yield quality

Abstract

ABSTRACTIn view of its importance for human nutrition, the European Commission funded a collaborative research programme (1998–99) to evaluate the impact of future increases in atmospheric ozone (O3) and carbon dioxide (CO2) concentrations on yield and tuber quality in potato (Solanum tuberosum L.). This was the first large‐scale open‐top chamber project to provide field‐based data spanning a wide range of European climatic conditions and ozone concentrations for a widely used cultivar, cv. Bintje. Intensive measurements of physiological and developmental effects were made throughout crop growth to improve the mechanistic understanding of the processes involved. Analysis of the experimental results and modelling work based on the extensive database revealed that the increasing tropospheric O3 concentrations predicted under future climatic scenarios in Europe are likely to reduce tuber yield in potato. However, season‐long exposure to elevated O3 had both beneficial and detrimental effects on tuber quality. Most of the significant physiological and growth effects occurred during the later stages of crop development, when elevated O3 reduced photosynthesis and promoted senescence. The observed changes in the quality and nutritional attributes of tubers, such as decreased content of reducing sugars and increased nitrogen concentrations, may be attributable to reduced carbohydrate allocation.