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Corylus Avellana L. (corylus + avellana_l)
Selected AbstractsDetecting vegetable oil adulteration in hazelnut paste (Corylus avellana L.)INTERNATIONAL JOURNAL OF FOOD SCIENCE & TECHNOLOGY, Issue 3 2009Josep Serra Bonvehi Summary The possibilities of detecting hazelnut paste adulterated with refined and non-refined vegetable oils have been studied. Research was focussed mainly on peanut, high oleic-acid sunflower, corn and soybean oils which have a similar composition to hazelnut oil. The analytical procedures to detect fatty acid (FA), triacylglycerol (TAG) and tocopherol profiles as indicators of adulteration were determined. The better indicators experimentally determined were seven FA (palmitic, stearic, linoleic, linolenic, arachidonic, behenic and lignoceric acids) and different TAG with three unsaturated FA (the code letters used for FA are: P = C16:0; S = C18:0; O = C18:1; L = C18:2;; Ln = C18:3) (LLLn, LLL and OOO), two unsaturated FA (POL, PLL and SOO), and one unsaturated FA (PPL). As expected, when refined vegetable oils were added to hazelnut paste, the increment of stigmasta-3,5-diene allowed detection at levels of 2% oil added. Limits of detection were measured using standard and adulterated hazelnut with different amounts of non-refined vegetable oils added (5%, 10%, 20% and 30%). The distribution of tocopherols and tocotrienols is highly useful, except in the case of added sunflower oil. The differences between the experimental and theoretical values of the TAG with equivalent carbon number (,ECN) of 42 does not improve the detection limit of hazelnut paste adulterated with peanut or sunflower oils. Similarly, tocopherols usually added to refined vegetable oils as an antioxidant were also determined. [source] Occurrence of Pseudomonas syringae pv. coryli on Hazelnut Orchards in Sicily, Italy and Characterization by Fluorescent Amplified Fragment Length PolymorphismJOURNAL OF PHYTOPATHOLOGY, Issue 7-8 2007G. Cirvilleri Abstract Field surveys for ascertaining the sanitary status of hazelnut (Corylus avellana L.) orchards located in the provinces of Catania and Messina, Sicily, were carried out. Twig and branch diebacks were frequently observed on the local hazelnut cultivars. Identification of the bacterial pathogen associated with these symptoms was performed by means of biochemical, pathogenicity and molecular tests as well as by using fluorescent amplified fragment length polymorphic (fAFLP) analysis. The study revealed, for the first time, the presence of Pseudomonas syringae pv. coryli in the Sicilian hazelnut orchards. All the strains obtained did not show the presence of syrB gene. The fAFLP analysis pointed out the presence of three different lineages within the strains of this pathogen. [source] Occurrence of Pseudomonas avellanae (Psallidas) Janse et al. and related pseudomonads on wild Corylus avellana trees and genetic relationships with strains isolated from cultivated hazelnutsJOURNAL OF PHYTOPATHOLOGY, Issue 9-10 2000M. Scortichini Surveys in submediterranean forests of central Italy were carried out during 1996,98 to verify the possible presence of bacterial canker caused by Pseudomonas avellanae in wild hazelnut trees (Corylus avellana L.). Wilted twigs were noticed several times especially in summer. In other cases, wild C. avellana trees growing near to hazelnut orchards appeared completely wilted. Isolates that were pathogenic to C. avellana, showing a different degree of virulence, were obtained in both situations. Biochemical, physiological and nutritional tests as well as the comparison of whole-cell protein profiles, revealed the presence of 16 isolates identical to P. avellanae reference strains that had previously been isolated in the same area and five deviating isolates. Repetitive-PCR genomic fingerprinting performed by using BOX (Box elements), ERIC (Enterobacterial Repetitive Interkingdom Consensus) and REP (Repetitive Extragenic Palindromic) primer sets and analysed by means of upgma, revealed the existence of two main groups of pseudomonads pathogenic to C. avellana. Group A includes P. avellanae strains isolated in northern Greece and central Italy as well as the isolates obtained from the wild C. avellana trees grown near the cultivated hazelnut orchards. Group B includes strains previously isolated in northern, southern and other areas of central Italy as well as the isolates obtained from C. avellana wild trees showing twig dieback. Control measures should be taken to avoid the spread of bacterial canker of hazelnut in the forests of central Italy. [source] Rapid identification of pseudomonas avellanae field isolates, causing hazelnut decline in central italy, by repetitive PCR genomic fingerprintingJOURNAL OF PHYTOPATHOLOGY, Issue 3 2000M. Scortichini Pseudomonas avellanae is the main cause of hazelnut (Corylus avellana L.) decline, the so called ,moria', in central Italy where it has already killed more than 30 000 trees. Its current identification is very long requiring biochemical, physiological and nutritional tests as well as pathogenicity tests and takes not less than 6 months for its completion. In the present study the reliability of the repetitive polymerase chain reaction (rep-PCR) technique for a rapid and accurate identification of such a pathogen was compared with the traditional identification method. In order to assess the variability of the pathogen, REP, BOX and ERIC primer sets were used in preliminary work to generate genomic fingerprints of 60 P. avellanae reference strains previously isolated from different areas of hazelnut cultivation. ERIC primers yielded the most discriminative clustering of strains that were grouped according to their geographic origin. Sixty field isolates collected from hazelnut orchards of central Italy, planted with different cultivars, during the years 1996,98 were submitted to either the traditional identification methods or to rep-PCR by using ERIC primers. The latter technique accurately identified all the isolates that were also identified by the traditional methods. Whole-cell protein analysis by means of sodium dodecyl sulphate-polyacrylamide gel electrophoresis confirmed this achievement. Rep-PCR can be successfully adopted for the rapid and accurate identification of P. avellanae in central Italy and it constitutes a very useful tool for the sanitation of the area. Zusammenfassung Eine schnelle Bestimmung von Pseudomonas avellanae -Feldisolaten, dem Erreger einer HaselnuIapoplexie in Zentralitalien, durch rep-PCR genomisches Fingerprinting [source] Antioxidant and Pigment Composition during Autumnal Leaf Senescence in Woody Deciduous Species Differing in their Ecological TraitsPLANT BIOLOGY, Issue 5 2003J. I. García-Plazaola Abstract: Photoprotection mechanisms have been studied during autumnal senescence in sun and shade leaves of woody plants with different ecological characteristics and senescence patterns. Three of them belonging to the same family, Betulaceae: the shade-intolerant and early successional species (Betula alba L.), the shade-tolerant and late successional species (Corylus avellana L.), and an N-fixing tree with low N resorption efficiency (Alnus glutinosa L.). The other two species: a shade-intolerant (Populus tremula L.) and a shade-tolerant (Cornus sanguinea L.), were chosen because of their ability to accumulate anthocyanins during autumnal leaf senescence. The study of plants with different ecological strategies allowed us to establish general trends in photoprotection mechanisms during autumnal senescence, when nutrient remobilisation occurs, but also during whole leaf ontogeny. We have not found a clear relationship between shade tolerance and the level of photoprotection; the main difference between both groups of species being the presence of ,-carotene in shade leaves of shade-tolerant species. Preceding autumn, nitrogen resorption started in mid-summer and occurred in parallel with a slight and continuous ascorbate, chlorophyll and carotenoid degradation. However, the ascorbate pool remained highly reduced and lipid oxidation did not increase at this time. Contrasting with ascorbate, ,-tocopherol accumulated progressively in all species. Only during the last stages of senescence was chlorophyll preferentially degraded with respect to carotenoids, leading to the yellowing of leaves, except in A. glutinosa in which a large retention of chlorophyll and N took place. Senescing leaves were characterised, except in C. sanguinea, by a relative increase in the proportion of de-epoxidised xanthophylls: zeaxanthin, antheraxanthin and lutein. The light-induced accumulation of anthocyanins in C. sanguinea could play an additional protective role, compensating for the low retention of de-epoxidised xanthophylls. These different strategies among deciduous species are consistent with a role for photoprotective compounds in enhancing nitrogen remobilization and storage for the next growing season. [source] Genetic diversity in hazelnut (Corylus avellana L.) cultivars from Black Sea countries assessed using SSR markersPLANT BREEDING, Issue 4 2010K. Gürcan With 6 figures and 6 tables Abstract European hazelnut (Corylus avellana L.) is an important crop in Turkey, Georgia and Azerbaijan, where cultivars were selected from the native vegetation. Accessions from Turkey have been assigned to the Black Sea group, and cultivars from Georgia and Azerbaijan have a similar phenotype. Genetic diversity was investigated in 88 accessions from these three countries and compared with cultivars from Spain and Italy using 12 microsatellite loci. A high level of genetic diversity (He = 0.71, Ho = 0.70) was observed in the Black Sea accessions. Six Turkish accessions in the US hazelnut collections were found to be synonyms of cultivars in the Turkish collection in Giresun. An unweighted pair-group method using arithmetic average dendrogram and principal component analysis of 109 unique accessions showed a tendency to form subgroups by country of origin, and high diversity within each subgroup. A moderate shift in allelic frequencies (FST = 0.114,0.131) was seen between accessions from the Black Sea and the Spanish-Italian accessions. Simple sequence repeat analysis identified the putative parents of two Turkish cultivars. [source] Genetic diversity revealed by morphological traits and ISSR markers in hazelnut germplasm from northern SpainPLANT BREEDING, Issue 4 2010J. J. Ferreira With 3 figures and 4 tables Abstract Hazelnut (Corylus avellana L.) has been a traditional crop in northern Spain. As a result of germplasm exploration over 3 years (2003,05), 90 trees were selected in this region. This study describes phenotypic variation in nut and husk traits and investigates genetic relationships among selections and cultivars using inter simple sequences repeat (ISSR) markers. The local selections were phenotypically diverse and many had characteristics appreciated by the market. Eleven ISSR primers, which generated 66 polymorphic bands, were used in the analysis. The graph from principal coordinates analysis of the molecular marker data showed two main groups, one for the local selections and the other for the standard cultivars. The dendrogram generated from UPGMA cluster analysis showed the same two main groups. The results suggest that the local accessions are closely related to each other, but are relatively distant from the standard cultivars of eastern Spain, Italy and the USA. Selections from northern Spain may be directly useful as new cultivars or alternatively as parents in breeding programmes. The collection and preservation of this genetic diversity is important. [source] | ||||||||||