Sustainable strategies for the preservation of cereals and legumes in developing countries

The project “Production of appropriate food: sufficient, safe, sustainable” aims to improve the nutritional conditions of the population in three areas of the world with a different level of development (Italy, India, Congo) through improvements in the agricultural system and in feeding education. Since surveys in villages of India and Congo showed that the preservation of foodstuffs from pest infestation is a major problem, our study was carried out in Italy to investigate the efficacy of different strategies to reduce the infestation level by physical (FAO metal silos) or chemical methods (treatment of the external surfaces of jute sacks and terra cotta jars). The experimental design, including the choice of cereals (paddy rice and beans), location (feedstuffs warehouse) and preservative structures (sacks and jars), tried to simulate the village conditions. Two commercial insecticides based on natural extracts (azadirachtin and pyrethrins) and an extract of propolis were used. These chemicals can be found in the interested countries, allowing a sustainable management during the post-harvest period. Metallic silos gave the most effective preservation of the grains (no infestation in 6 months). Among chemicals, the best results were given by azadirachtin: both its repellent and insecticide effects allowed a good preservation of the product up to 4.5 months, while after 6 months the infestation level was only 27% of the untreated control. Jute sacks always showed a lower protection than jars.