Maize is one of the most important crops for European agriculture. The energetic value and high nutritional quality makes maize silage a basic element for animal feeding. Since maize originates from tropical regions it is particularly sensitive to low-temperature stress, explaining why stress tolerance has become a major selection criteria in maize breeding programmes. The damage caused by low-temperature stress occurs primarly in the chloroplasts, leading to an early inhibition of photosynthesis, photobleaching of pigments, and considerable losses in quality and yield. It is generally accepted that free radicals play an important role in the destruction of the photosynthetic apparatus and pigments. The working hypothesis of this proposal is that transgenetic plants with an improved scavenging system for free radicals in the chloroplasts will be significantly better protected against lowtemperature stress. To this end, transgenic maize plants will be generated which over express in the chloroplasts both a superoxide dismutase and an enzyme implicated in hydrogen peroxide scavenging (ascorbate peroxidase, glutathione peroxidase, catalase, glutathione reductase, or glutathione synthetase). Two participants have an extensive expertise with the molecular analysis of oxidative stress in plants. The maize transformation will be performed by a novel and highly efficient system developed by one of the participants. Transgenic maize plants overexpressing oxyradical-scavenging enzymes will be analysed in detail by biochemical and biophysical methods to quantify the level of tolerance to low-temperature stress. These tasks will be shared by three participants, all of whom are very experienced in this type of analysis. Finally transgenic lines with a higher tolerance to low-temperature stress will be evaluated in field conditions. An improved tolerance to low temperate will contribute considerably to the competitiveness of European agriculture. It is expected that stress-tolerant maize varieties could be grown at lower cost and over an extended area in northern Europe.
Funding SchemeCSC - Cost-sharing contracts
CO4 3SQ Colchester