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241.
Sesame seeds are an excellent food and non-food raw material, for which there is a consolidated deficit in Italy and in other European Union countries. For this reason, a 2-years experiment was conducted in Sicily to compare the agronomic performance (phenology, morphological and productive traits) and grain quality (oil and its main constituents, protein of defatted flour, fibre) of three landraces, one of Turkish origin and two Sicilian (“Ispica” and “Modica”), and two improved varieties (‘Pachequino’ and ‘Yori 77’). The landraces evidenced earliness (115 days) and the greater height of insertion of first capsule (0.52 m), whereas the variety ‘Pachequino’ was the most productive (3.5 t ha?1). Turkish and “Ispica” landraces and ‘Yori 77’ variety provided seeds with greater lipid (54 %, on average) and protein contents (44 % on defatted flour, on average). ‘Pachequino’ and both Sicilian landraces produced seeds richer in fibre fractions. As regard to oil quality, the oleic acid/linoleic acid was found balanced (about 1) for Turkish landrace, and it decreased for the other cultivars reaching the lowest value for ‘Pachequino’. “Modica” had higher quantity of unsaponifiable matter (1.98 %) in the oil, whereas ‘Yori 77’ had the maximum concentration of phytosterols (5532.8 mg kg?1). Policosanol fraction prevailed in oil of “Ispica” (205.8 mg kg?1). Moreover, there was variability in the fatty acid, sterol and policosanol compositions with differences among the cultivars. Research provide information to exploit sesame within agrosystems under Mediterranean climates, and may be a starting point for breeding activity to enhance crop productivity and grain quality.  相似文献   
242.
The objective of the present study was to evaluate the effect of three common cooking practices (i.e., boiling, steaming, and frying) on phytochemical contents (i.e., polyphenols, carotenoids, glucosinolates, and ascorbic acid), total antioxidant capacities (TAC), as measured by three different analytical assays [Trolox equivalent antioxidant capacity (TEAC), total radical-trapping antioxidant parameter (TRAP), ferric reducing antioxidant power (FRAP)] and physicochemical parameters of three vegetables (carrots, courgettes, and broccoli). Water-cooking treatments better preserved the antioxidant compounds, particularly carotenoids, in all vegetables analyzed and ascorbic acid in carrots and courgettes. Steamed vegetables maintained a better texture quality than boiled ones, whereas boiled vegetables showed limited discoloration. Fried vegetables showed the lowest degree of softening, even though antioxidant compounds were less retained. An overall increase of TEAC, FRAP, and TRAP values was observed in all cooked vegetables, probably because of matrix softening and increased extractability of compounds, which could be partially converted into more antioxidant chemical species. Our findings defy the notion that processed vegetables offer lower nutritional quality and also suggest that for each vegetable a cooking method would be preferred to preserve the nutritional and physicochemical qualities.  相似文献   
243.
A field experiment was carried out to investigate the effect of fertilization level on the phenolic composition of tronchuda cabbage ( Brassica oleracea L. var. costata DC) external and internal leaves. Eight different plots were constituted: a control without fertilization, one with organic matter, and six experiments with conventional fertilizers (nitrogen, boron, and sulfur, two levels each). The phenolic compounds were analyzed by reversed-phase HPLC-DAD. External and internal leaves revealed distinct qualitative composition. In the internal leaves were found 15 phenolics (5 kaempferol and 10 cinnamic acid derivatives), whereas the external leaves presented 3- p-coumaroylquinic acid and 13 kaempferol derivatives. Principal component analysis (PCA) was applied to assess the relationships between phenolic compounds, agronomical practices, and harvesting time. Samples obtained with conventional practices were quite effectively separated from organic samples, for both types of leaves. In general, samples developed without any fertilization presented the highest phenolics amounts: external and internal leaves contained 1.4- and 4.6-fold more phenolic compounds than the ones that received conventional fertilizer, respectively, and the internal leaves presented 2.4 times more phenolics than the ones grown with organic amendment. Additionally, samples from organic production exhibited higher total phenolics content than those from conventional practices, collected at the same time. Samples harvested first were revealed to be distinct from the ones collected later. The results show that it is possible to grow tronchuda cabbage without excess fertilizers, with highest amounts of phenolics and reduced environment contamination.  相似文献   
244.
The free amino acid profile of 18 samples of tronchuda cabbage ( Brassica oleracea L. var. costata DC) leaves, harvested at three different months, was determined by HPLC/UV-vis. The tronchuda cabbage leaves total free amino acid content varied from 3.3 to 14.4 g/kg fresh weight. Generally, arginine was the major compound, followed by proline, threonine, glutamine, cysteine, and glutamic acid. This study indicates that free amino acids are not similarly distributed: in external leaves, proline and arginine were the major free amino acids, while in internal ones, arginine was the main free amino acid, followed by threonine, glutamine, and cysteine. Significant differences were observed for valine, proline, arginine, leucine, cysteine, lysine, histidine, and tyrosine contents. The levels of some free amino acids were significantly affected by the collection period. In external leaves, this occurred with glutamic acid, serine, valine, leucine, cysteine, and ornithine contents, while in internal leaves, it occurred with aspartic acid, arginine, and total contents.  相似文献   
245.
Journal of Plant Diseases and Protection - The efficacy of different fungicides, belonging to different chemical groups, was in vitro and in vivo tested in glasshouse trials against Allophoma...  相似文献   
246.
Leaf spot of tomato, incited by Pseudomonas syringae pv. syringae, has been reported recently in Italy on grafted and non-grafted tomato plants (scion Cuore di Bue, rootstock Solanum lycopersicum x Solanum hirsutum cv. Beaufort). In some greenhouses, more than 80% of plants were affected, with a marked reduction in yield. This work was undertaken in order to understand the effect of the number of hours of incubation at high relative humidity (r.h.) and temperature as well as the effect of the presence of wounds at infection time on the development of leaf spot. A difference in sensitivity to leaf spot was observed in the various cultivars tested, in terms of severity of P. syringae pv. syringae, with “Cuore di Bue” being the most susceptible of these cultivars. The development of leaf spot is mostly favored by the presence of wounds, at temperatures between 15 and 20°C. The severity of the disease is lower at 10 and 25°C and very low at 30°C. Under the most favorable temperature conditions, the presence of wounds is sufficient to allow the development of the pathogen immediately upon incubation at high r.h. The effect of wounds and the relatively low requirement of hours of incubation at high r.h. suggest the need for careful management and handling of plants when temperatures range between 15 and 25°C, and particularly within 15 and 20°C. All operations carried out, particularly at transplant and immediately after, should avoid the creation of wounds.  相似文献   
247.
248.
Neotropical freshwater fishes are the most diverse on the planet (>5,500 species), although nations in Latin America have been negligent regarding their conservation. National policies have historically encouraged unsustainable practices, and recent decades have witnessed a sharp increase in harmful activities. Our aim with this review was to expose this situation and illustrate how national policies constitute the main threat to freshwater fish biodiversity. We explain that the most devastating, pervasive and systemic threats are rooted in official policies, particularly unsustainable activities (e.g. hydropower, water diversion, mining, aquaculture, agriculture and fishing), poor management/conservation (e.g. fish stocking and passages) and harmful legislation (e.g. poor licensing, non‐native species). We provide a broad portrait of the Neotropical scenario, where unsustainable policies have caused considerable damage to freshwater ecosystems, and focus on major examples from Brazil, where development projects have caused large‐scale losses to fish biodiversity. Such modus operandi of human development is incompatible with the persistence of biodiversity, and no simple solution is available to correct or minimize its effects. The current situation demands a profound behavioural shift towards better practices and policies, or these multiple high‐impact activities will continue eroding freshwater fish biodiversity and impairing essential ecosystem services.  相似文献   
249.
The inheritance of the red colour character in European pear (Pyrus communis L.) was studied over 3 years in seven progeny obtained by using the cultivars ‘Max Red Bartlett’, ‘Cascade’ and ‘California’ as red‐skinned fruit parental lines. One of these progeny (derived from the cross ‘Abbé Fétel’ × ‘Max Red Bartlett’, a red mutation of ‘Bartlett’) was already used to construct two linkage maps and, being ‘red colour’ a monogenic dominant trait, it was possible to locate it as morphological marker in the linkage group 4 of ‘Max Red Bartlett’. For the first time, this trait has been mapped out of linkage group 9 in a species belonging to the Maloideae subfamily moreover in a mutated sport. An improved knowledge of the genetic basis of production and accumulation of red pigments in the fruit skin will better support the pear breeding programmes aimed to select new cultivars carrying this appealing trait.  相似文献   
250.
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