6 research outputs found
Naleving van milieurecht. Toepassing van beleidsinstrumenten op de Nederlandse verfindustrie
Prevention is one of the leading principles in current Dutch environmental policy. This study focuses on the effects of policy instruments that are aimed at prevention. The two main questions that we have raised were: how can differences between factories in success or failure of preventive policy measures be explained? How can differences between policy instruments in success or failure of preventive policy measures be explained? ...
Zie: Summary.
The association between the susceptibility to Botrytis cinerea and the levels of volatile and non-volatile metabolites in red ripe strawberry genotypes
The relations between physical and chemical characteristics (e.g., color, firmness, volatile and non-volatile metabolites) of red ripe strawberry fruit and the natural spoilage caused by Botrytis cinerea were investigated. The spoilage rates differed between genotypes, and this was highly correlated over two successive years. Among seventeen genotypes, a more intense red coloration of the fruit skin was associated with a lower spoilage rate (r = â0.63). Additionally, weakly negative correlations were found between the levels of anthocyanins, ascorbic acid, malic acid and spoilage rates. No clear correlations were found between spoilage rates and soluble sugars, most volatiles, firmness and dry weight percentage. High levels of two volatile compounds, ethyl butanoate (r = 0.55) and 1-hexanol (r = 0.61), were correlated to high spoilage rates. These characteristics may assist strawberry breeders in selecting for genotypes with reduced susceptibility to B. cinerea
Differences in N uptake and fruit quality between organically and conventionally grown greenhouse tomatoes
Soil-bound intensive greenhouse production has been scrutinized for its sustainability due to contamination of ground water by over-fertilization resulting in leaching of nutrients. As environmental guidelines are becoming more restrictive worldwide, and especially in Europe, many greenhouse growers have converted to more sustainable production systems including rockwool culture with recycled water and organic cropping systems in soil. The increase in popularity of organic production systems has amplified the debate whether organically grown produce is healthier than conventional produce. So far, little is known about the variations in fruit quality associated with production systems for greenhouse grown tomatoes. Thus, two organic (organic fertilization with and without straw amendment) and three conventional tomato cropping systems (regular and increased nutrient solution in rockwool and regular fertilization in soil) were compared in order to evaluate differences in nutrient availability and effects on fruit quality over a three-year period. Three modern medium-sized round tomato cultivars and one old cultivar were compared. There were no significant interactions between cropping systems and cultivars, so that main effects of systems and cultivars could be evaluated. Fruit yields in the organic systems were similar to those obtained in the conventional soil-bound system, but 15% lower than in the regular rockwool system, even though nitrogen concentrations in soil were not limiting in any of the production systems. Frequent organic amendments resulted in higher soil contents in the organic system without straw than in the other soil-bound systems, indicating that the organic systems were not yet stable in terms of nutrient availability after three years. A fruit quality index, based on the contents of compounds such as lycopene, ÎČ-carotene and vitamin C, was similar in all cropping systems. The old cultivar had a significantly higher quality index, but a lower yield than the other cultivars. According to this study, high quality tomatoes can be obtained through proper adjustment of the quantity and the source of nitrogen fertilizers in organic and conventional cropping systems and the use of selected cultivars with a high nutrient use efficiency for organic systems