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81.
Emmer wheat is hulled wheat that was wide cultivated in Spain at the past. Actually, the most of this germplasm is conserved in Germplasm Banks, and only two small populations have been found in Asturias (North of Spain) in a recent collecting mission. In this work, a collection of 31 Spanish emmer lines developed from identical number of accessions of two Germplasm Banks was analysed for morphological spike traits and seed storage protein composition. Up to seven different botanical varieties were detected, which suggest the presence of a wide diversity, although lower than the historically described 10 botanical varieties. At level of seed storage proteins, the lines showed a high diversity, although the new alleles were present with low frequency in materials with scarce agronomic interest for the farmers (var. atratum, var. lagascae or var. pycnurum). This last circumstance could translate in a lost of variability by genetic drift.  相似文献   
82.
OBJECTIVE: To demonstrate how dietary data collected from 24-hour dietary recalls were incorporated into the development of a quantitative food-frequency questionnaire (QFFQ) for the Apache in Arizona. DESIGN: A cross-sectional study was first conducted using 24-hour dietary recalls to identify foods for inclusion on a QFFQ that would be used to evaluate a nutrition intervention. SETTING: The White Mountain and San Carlos Apache reservations in East-central Arizona. SUBJECTS: The 24-hour dietary recalls were collected from a random sample of 53 adults (34 women and 19 men). RESULTS: A QFFQ was developed that included all foods reported by two or more respondents, plus traditional and seasonal foods. Portion size was assessed using familiar household units and culturally appropriate food models. The final instrument contains 155 foods. Frequency of consumption is assessed using eight categories ranking from 'never or less than once a month' to '2 or more times a day'. Nutrient intakes and the five major food sources of energy, fat and sugar are presented. CONCLUSION: The QFFQ developed is complete and up-to-date for assessing usual food and nutrient intake for the Apache in Arizona. The instrument will be used to evaluate a food store-based nutrition intervention to reduce risk of chronic diseases.  相似文献   
83.
Thirty-two olive cultivar accessions from Syria, most of them obtained from collecting expeditions, were characterized by means of RAPD markers before being introduced in the World Germplasm Bank of Cordoba. A total of 79 polymorphic bands(6.1 polymorphisms per primer) out of 93(7.1 bands per primer) were scored for the13 primers used, corresponding to 84.9% of the amplification products. Thirty-one different genotypes were clearly discriminated. Differences were not found among the amplification profiles from different individuals of the same cultivar. Only two cases of mislabeling or errors of planting were found. Fourteen accessions corresponding to 6 homonyms were discriminated by RAPDs as different genotypes. The dendrogram obtained by RAPD analysis included three major groups. Some evidence of relationships of the Syrian accessions studied according to their geographic origin and/or diffusion was found. For instance, cultivars from the Central Syria (Tadmur/Palmyra)such as Toffahi', ‘Abbadi Abo Gabra’-1033,‘Abo Kanani’, ‘Shami’-1041, ‘Abbadi Shalal’ ‘Adgam’-844 and ‘Majhol’-1013 clustered in Group 1 and 2. Six cultivars from Northern Syria clustered in Group 2. But it was not found a geographic structure for the cultivars from South and West of Syria. These results agree with the hypothesis of autochthonous origin of most of the olive cultivars. Some associations between cultivars from Central Syria and their fruit size were observed. This suggests that fruit size was a criterion of local selection in olive cultivars of this area. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   
84.
Granule‐bound starch synthase of ancient wheat and related species was examined by sodium dodecyl sulphate polyacrylamide gel. A total of 13 different alleles were revealed in a collection of three accessions of diploid wheat, six accessions of tetraploid wheat, 49 accessions of spelt wheat, nine accessions of Sitopsis and two accessions of Aegilops tauschii. A new allele named Wx‐A1a′ appeared in four spelt wheat accessions. The tetraploid wheat accessions evaluated did not show any polymorphism; nevertheless the tetraploid accessions of Sitopsis section revealed three novel alleles. The novel allele Wx‐Ddn1g was found in two accessions of A. ventricosa and the Wx‐Ddcm1h and Wx‐Ddcm1i in two accessions of A. crassa. A novel allele named Wx‐Au1g was found in Triticum urartu, which is different from the also new Wx‐Am1h allele of T. monococcum. The diploid‐related species accessions revealed two novel alleles named Wx‐Bsl1h and Wx‐Bs1g found, respectively, in A. longissima and A. speltoides. The amylose content was measured for the different alleles found in all evaluated species and no significant effects of the allele composition on the amylose content were detected.  相似文献   
85.
86.
Nutrient deficiencies usually constrain the use of some composted materials as peat-substitute growing media even if some fertilizer is applied to the media. In this work, we assessed the suitability of various composted materials as such or mixed with peat for potted plant production, with special emphasis on their effects on nutrient availability to plants. Further, we examined the effect of vivianite [Fe3(PO4)2·8H2O] as a fertilizer and its mixture with humic substances (HS) on these growing media (particularly their effectiveness in preventing Fe deficiency chlorosis in alkaline substrates). A completely randomized experiment design was developed involving the growth of gerber (Gerbera jamesonii H. Bolus) and two factors, namely (i) the growing medium, specifically composted cork residue (C), compost obtained from a mixture of olive husk and cotton gin trash mixed with rice hulls and peat in a 1:1:1 volume proportion (OH), composted grape marc (GM), Sphagnum peat mixed with spent mushroom compost (M), coconut fibre (CF), and Sphagnum peat; and (ii) the Fe source (control without Fe, Fe-EDDHA, vivianite and vivianite + HS in a weight ratio of 10:1).  相似文献   
87.
We propose coefficients for regressions relating dry weight to body or tergite length in Folsomia candida, Entomobrya schoetti, Sminthurus viridis, and Hypogastrura vernalis (Collembola). Measurements were made on large batches of preserved, identified specimens. Batches were dessicated completely by critical-point drying and weighed. We compare our data with other published models and critically review the literature, finding questionable records.  相似文献   
88.
89.
One of the most used thermal treatments in potatoes to inactivate enzymes and prevent their oxidation is the boiling process. This treatment significantly decreases the taste of the potato and causes “off-odours” during storage, whatsoever, represents a big problem for the production of potato-based foodstuffs. This study focused on evaluating the sensory profile of potato slices subjected to a boiling process of three Mexican potato varieties (Alpha, Chica and Gallo) and on off-odours detection in potato produced during storage. According to the examined parameters through PanelCheck, the trained panel had a good performance, resulting 8 of the 12 attributes evaluated were significant. The formation of “cardboard-like off-odour” was detected in the Alpha and Chica varieties at the 24 and 33 h of storage, respectively. Chica potato presented this off-odours with at level significantly lower than Alpha potato (about 30% lower). With respect of Gallo variety, this presented different oxidation olfactory perceptions described by the assessors as “burnt note”, detected after 5 h of refrigerated storage. An adequate election of the variety of potato according to processing will allow an effective utilization of this vegetable and the obtention of potato-based foodstuffs much more stable.  相似文献   
90.
This paper presents an effective method for prioritizing areas within a country for acquisition of germplasm of a crop gene pool for ex situ conservation. The method was applied to the rare wild pepper species, Capsicum flexuosum Sendtn., in south-east Paraguay. A model to prioritize areas for collecting germplasm was constructed by combining (1) a prediction of the species' geographic distribution based on the climate at previous collection points, (2) the distribution of forest margins (the species' natural habitat) and (3) areas accessible by road. The model was then tested in the field by visiting 20 sites having both high and low predicted probability of occurrence of C. flexuosum. Six new populations were found, representing a significant improvement over two previous collecting missions for the species in the same region, undertaken without the use of GIS targeting. Using the most optimistic analysis of model performance, C. flexuosum was found at five out of seven points predicted to harbour the species and not found at four of five points predicted not to harbour the species. The model was then improved by the use of higher resolution climate surfaces. It is recommended that future explorers use more recent and higher resolution satellite images to locate suitable habitats. The method is replicable for different species in different geographic regions and is offered as a means of optimizing efficiency in financially constrained, national plant genetic resources programs.  相似文献   
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