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排序方式: 共有916条查询结果,搜索用时 15 毫秒
911.
Changes in antioxidant content of tomato fruits in response to cultivar and nutrient solution composition 总被引:1,自引:0,他引:1
Fanasca S Colla G Maiani G Venneria E Rouphael Y Azzini E Saccardo F 《Journal of agricultural and food chemistry》2006,54(12):4319-4325
The aim of this study was to investigate the effect of cationic proportions (K/Ca/Mg) in the nutrient solution on fruit quality (quality attributes and antioxidant content) using a high-pigment, 'Lunarossa', tomato cultivar and a standard tomato cultivar ('Corfù') grown in soilless culture. Treatments were defined by a factorial combination of three nutrient solutions having different cationic proportions and two indeterminately growing round tomato cultivars. A high proportion of K in the nutrient solution increased the quality attributes (fruit dry matter, total soluble solids content) and the lycopene content of tomato fruit, whereas a high proportion of Ca improved tomato fruit yield and reduced the incidence of blossom-end rot (BER). The highest total antioxidant activity was observed in the treatment with a high proportion of Mg in the Lunarossa cultivar. The high-pigment hybrid has provided a higher antioxidant content (lycopene and alpha-tocopherol content) than the commercial hybrid, but it was more susceptible to BER and consequently less productive. 相似文献
912.
913.
914.
Chizhikova Nataliya Korobova Elena Linnik Vitaly Chechetko Ekaterina 《Journal of Soils and Sediments》2018,18(6):2410-2417
Journal of Soils and Sediments - The main goal of this research was to compare and reveal the difference in the character of Cs-137 distribution and fixation in fine fractions of alluvial soils... 相似文献
915.
The worldwide increase of human pressure in rural areas has resulted in a progressive fragmentation of agro-forest landscapes. Relatively few studies have identified processes of landscape modification and patch fragmentation reflecting long-term human activity from those caused by recent urbanization stimulated by economic development, population growth and improved accessibility of rural areas. In rural districts dominated by high-quality crop mosaics and exposed to increasing levels of human pressure, urbanization-driven changes in the use of land have determined complex and non-linear processes of landscape fragmentation which deserve further investigation. Multidimensional procedures and data mining are appropriate to explore such transformations, basing on a comprehensive assessment of landscape metrics. The present study investigates changes in land-use and landscape structure (2000–2008) in three districts of Latium (central Italy) featuring different cropping systems, physiographic attributes and level of human pressure. A principal component analysis was run to identify a core set of metrics aimed at (i) evaluating the role of traditional cropping systems in the preservation of traditional agro-forest systems and (ii) inferring the relationship between spatial heterogeneity in rural landscapes and socio-ecological processes of change. Our results indicate that crop intensification has contributed to landscape homogeneity and simplification in all areas studied, in contrast with the effects of urban expansion resulting in a more fragmented and diversified landscape with relict tree crop patches. The findings of this study clarify the contribution of traditional tree crop systems to sustainable structures and functions of rural landscapes by preserving the place-specific eco-mosaic complexity. 相似文献
916.
Juan Carlos C. Fuentes-Monteverde Nilamoni Nath Abel M. Forero Elena M. Balboa Armando Navarro-Vzquez Christian Griesinger Carlos Jimnez Jaime Rodríguez 《Marine drugs》2022,20(7)
The seaweed Sargassum muticum, collected on the southern coast of Galicia, yielded a tetraprenyltoluquinol chromane meroditerpene compound known as 1b, whose structure is revised. The relative configuration of 1b was determined by J-based configurational methodology combined with an iJ/DP4 statistical analysis and further confirmed by measuring two anisotropic properties: carbon residual chemical shift anisotropies (13C-RCSAs) and one-bond 1H-13C residual dipolar couplings (1DCH-RDCs). The absolute configuration of 1b was deduced by ECD/OR/TD-DFT methods and established as 3R,7S,11R. 相似文献