In most climates fruits can only be grown and harvested during a small part of the year. Yet, consumption of fruit, and hence demand occurs throughout the year. For this reason, large parts of the fruit harvests must be stored for more or less extended periods of time before they are sold to the consumers. Obviously, such storage causes considerable losses due to pathogen attack and natural senescence. The traditional solutions to these problems have been storage under controlled or modified atmospheres and the use of synthetic pesticides. Nevertheless, losses exceeding 20% are not uncommon. The 'FRUTA FRESCA' project proposes to develop a remedy both by improved monitoring of fruit quality and by reduction of fruit spoilage through enhancement of natural plant resistance. Our strategy is based on two breakthroughs in basic science, which can now be exploited for the benefit of European agriculture. The first is the identification of components of the natural defense response in plants which can be used not only as early and sensitive indicators for spoilage, but which can also be optimised in order to enhance resistance. The second is the enormous advance in laser technology which makes it now possible to detect natural defense molecules with unprecedented sensitivity, versatility and reliability.
Objective 1 On-line detection by laser techniques of the production of natural plant stresssignal and defense molecules such as ethylene, acetaldehyde, ethane, hexenal.
Objective 2 Exogenous application of natural pesticides and the enhancement of the endogenous concentration of such compounds, to enhance shelf-life of fruit.
This project brings together seven groups, together possessing an extensive experience in all aspects of the project, i.e. The laser technology, plant defense research, and the industrial application of such research. P1 and P3 have been at the basis of the new laser technologies. P2 and P5 have their background in the characterisation of natural plant defense molecules and have recently applied laser technology developed by P1 and P3. P4 has pioneered the application of lasers for use in plant defense research, and is now specialising on postharvest pathology. P7 has made significant developments in improving the quality of fruits using hot water wash and other related methods. In addition a specialised company, P6, will contribute not only to optimise and validation of the new techniques, but also to the verification of the improvement of fruit quality. The combined efforts of these groups and industry will lead to significant improvements in fruit storage and thereby in the competitiveness of an important branch of European agriculture.
1. 2 laser based techniques were developed to perform analysis of volatile (LPAS) and non-volatile (REMPI) compounds in fruits. Both techniques allowed a very sensitive detection able to monitor the health status of the fruit.
2. Ethylene & hexanal serve as a very sensitive signal of early infection and can be used to assess the health status of the fruit.
3. Molecular tools to study gene expression in tomato and Botrytis were developed.
4. Genetically altered tomato plants have been produced which show improve resistance to pathogenesis.
5. A new method to improve natural resistance in fruit has been found, consisting on external application of (natural or synthetised) resveratrol.
6. The improvement of the fruit quality has been verified by nutritional analysis and by sensory analysis with real consumers.
7. A new semi-commercial method to improve tomato quality has been developed, consisting of a short prestorage hot water rinse and brushing.
Funding SchemeCSC - Cost-sharing contracts
6500 GL Nijmegen