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191.
Summary Isozyme variation in 25 accessions of wild and cultivated Vigna unguiculata, 49 accessions of seven wild species belonging to section Vigna, and 11 accessions of V. vexillata (subgenus Plectrotropis) was scored at 17 putative loci to assess genetic relationships within and among species. The wild species selected for this study are among those which carry important agronomical traits useful in cowpea (V. unguiculata) breeding programs. Allelic frequencies were calculated and Nei's genetic distances were obtained. Low levels of intraspecific variation were observed for V. heterophylla, V. luteola and V. racemosa, whereas the other species showed a higher polymorphism. Vigna unguiculata possessed intraspecific genetic distances comparable to those previously found by other authors. Most of the isozyme variation was apportioned among species. Although V. luteola and V. marina had an interspecific genetic distance resembling the range observed at intraspecific level, all the other species showed very high interspecific distances. Vigna unguiculata was relatively closer genetically to V. vexillata than to the species belonging to section Vigna.Abbreviations AUS Australia - BDI Burundi - BRA Brazil - BWA Botswana - CAF Central African Republic - GHA Ghana - CMR Cameroon - COG Congo - RI Costa Rica - EGY Egypt - ETE Ethiopia - GAB Gabon - GRC Greece - ITA Italy - KEN Kenya - MOZ Mozambique - NER Niger - NGA Nigeria - PAN Panama - RWA Rwanda - TCD Chad - TZA Tanzania - ZAF South Africa - ZAR Zaire - ZMB Zambia  相似文献   
192.
Today, emmer wheat, T. turgidum subsp. dicoccon, widely grown in the past is a candidate crop for sustainable agriculture in Italy. As part of a research project aimed at the enhanced use of the hulled wheat germplasm, molecular characterization was carried out to understand the genetic structure of the crop and to identify accessions of interest. A collection of 194 accessions was analyzed with 15 microsatellite loci (SSRs), while only a sample of 38 accessions was tested with 19 RFLP probes. The marker loci were selected on the basis of their independent genomic distribution. Genetic distances and allelic frequencies were calculated for each marker class. The genetic relationships were visualized with dendrograms. RFLP loci were, on average, less polymorphic than SSRs. An average Dice's genetic distance of 0.22 for RFLPs vs 0.38 for SSRs was detected, while an expected average heterozygosity per locus of 0.23 for RFLPs vs 0.26 for SSRs was also estimated. With a least number of 10 loci per marker class it was possible to identify each genotype. The most diverse accessions had different geographic origins. Germplasms from Italy and Ethiopia appear to belong to a more primitive genepool, given that a group of accessions from these countries were genetically differentiated from a Russian-Iranian group.  相似文献   
193.
Essential oils extracted by hydrodistillation from fruits of Cuminum cyminum L. and Carum carvi L. were analyzed by gas chromatography (GC) and GC-mass spectrometry (MS). The main components of C. cyminum oil were p-mentha-1,4-dien-7-al, cumin aldehyde, gamma-terpinene, and beta-pinene, while those of the C. carvi oil were carvone, limonene, germacrene D, and trans-dihydrocarvone. Antibacterial activity, determined with the agar diffusion method, was observed against Gram-positive and Gram-negative bacterial species in this study. The activity was particularly high against the genera Clavibacter, Curtobacterium, Rhodococcus, Erwinia, Xanthomonas, Ralstonia, and Agrobacterium, which are responsible for plant or cultivated mushroom diseases worldwide. In general, a lower activity was observed against bacteria belonging to the genus Pseudomonas. These results suggest the potential use of the above essential oils for the control of bacterial diseases.  相似文献   
194.
Essential oils were extracted from the fruits of Coriandrum sativum L. and Foeniculum vulgare Miller var. vulgare (Miller) and assayed in vitro for antibacterial activity to Escherichia coli and Bacillus megaterium, bacteria routinely used for comparison in the antimicrobial assays, and 27 phytopathogenic bacterial species and two mycopathogenic ones responsible for cultivated mushroom diseases. A significant antibacterial activity, as determined with the agar diffusion method, was shown by C. sativum essential oil whereas a much reduced effect was observed for F. vulgare var. vulgare oil. C. sativum and F. vulgare var. vulgare essential oils may be useful natural bactericides for the control of bacterial diseases of plants and for seed treatment, in particular, in organic agriculture. The significant antibacterial activity of essential oils to the bacterial pathogens of mushrooms appears promising.  相似文献   
195.
Summary Carosello, a local vegetable from South Italy, is used in the same way asCucumis sativus but, in fact, it is a vegetable race ofCucumis melo. In the light of this local vegetable race which is presumed to be a relic of a former, more wide-spread cultivation, the infraspecific taxonomy ofCucumis melo together with some aspects of the history of melon systematics are discussed.Carosello is taken as an example to demonstrate that in the course of domestication of several completely unrelated taxa special varieties had been selected for the consumption of unripe fruits which are unpalatable when ripe in the majority of the cultivars of these species.
Carosello und die Taxonomie vonCucumis melo L. unter besonderer Berücksichtigung der Gemüsesippen
Zusammenfassung Carosello, eine lokale Gemüsesippe aus Süditalien, wird in der gleichen Weise wieCucumis sativus genutzt, ist aber eine Form vonCucumis melo. Im Lichte dieser lokalen Gemüsesippe, von der angenommen wird, daß sie das Relikt einer weiteren Verbreitung in früheren Zeiten ist, werden Fragen der infraspezifischen Taxonomie vonCucumis melo sowie Aspekte der historischen Entwicklung der Melonen-Systematik diskutiert.Carosello wird als Beispiel dafür herangezogen, daß im Verlaufe der Domestikation aus verschiedenen, nicht miteinander verwandten Taxa Sorten selektiert wurden, die im unreifen Zustand genutzt werden können, während sie zur Reife bei der Mehrheit der Sorten dieser Arten wenig schmackhaft oder sogar ungenießbar sind.

Carosello Cucumis melo L. ë
Carosello — , , Cucumis sativus, Cucumis melo. , , , ë , Cucumis melo, .Carosello , , , , .


Dedicated to the memory of I. S.Grebenikov (1912–1986), well-known researcher of the cultivated taxa of the cucurbit family, to whom we owe valuable stimulations for this paper.

Preliminary studies towards a Flora plantarum agri- et horticulturae Italiae australis.  相似文献   
196.
The paper aims at investigating the impact of the Great Recession on per capita GDP convergence process across European regions and countries. Using the time-varying factor model developed by Phillips and Sul for the period 2000–2015 and two different merging procedures to identify clubs, we provide evidence of the diverging impact of the Great Recession “between” the higher and the lower convergence clubs at both regional and country levels as well as of the strengthening of the convergence process “within” most clubs. In addition, we add further evidence to the common belief of a “multi-speed” Europe by contrasting Eastern European countries' and regions' behavior vis-à-vis original European members' one, and by identifying the factors that affect club membership and resilience to the recent economic downturn. We find that the membership in the higher clubs and resilience to the Great Recession are positively affected by the presence of several local-specific factors and macroeconomic characteristics.  相似文献   
197.
This paper refers on the yields and productive aspects of mineral and foliar nutrition of globe artichoke plants (cv. ‘Opal’ and ‘Madrigal’). Marketable yields were investigated in response to different nitrogen rates and foliar applications of biostimulating products. Field experiments were conducted over two seasons on an alluvial salty-clay soil in sub-humid climate conditions. Analyzed traits differed between years because of the age of plants while the lowest nitrogen rate and foliar spraying of biostimulants influenced significantly head weight, dry matter, and Soil Plant Analysis Division (SPAD) index. Biostimulants induced longer cultural cycle and heads lighter in weight. Cultivar ‘Madrigal’ was most productive than ‘Opal’, both in number (26.28% higher) and in weight (28.51%) of total heads. The two-year investigation showed that the synergic action was effective in improving some of the investigated productive traits of globe artichoke.  相似文献   
198.
A collection of 87 ancient wheat genotypes, 67 Triticum monococcum, 13 Triticum boeoticum, seven Triticum urartu and one cultivar of the modern wheat Triticum aestivum (variety ‘Arminda’) were evaluated for resistance to the cereal aphid Sitobion avenae, the main damaging aphid pest on winter wheat in Europe. The intrinsic rate of natural increase (rm), which is regarded as a good estimate of the fitness of an aphid population, was used as an indicator for the level of plant resistance. Differentiation of the 88 plant genotypes into four distinct groups was achieved with a cluster analysis of the rm values. The modern wheat ‘Arminda’ was more susceptible than any of the ancient wheat genotypes tested (rm= 0.24, i.e. the aphid population doubled every 2.6 days). A second group of 19 plants ranged from relatively susceptible to moderately resistant (0.17 < rm < 0.21). Fifty–one plants were allocated to a third group and classified as resistant (0.09 < rm < 0.16). The last group contained 17 genotypes with a high level of resistance where aphid fitness was greatly reduced (0.02 < rm < 0.09, i.e. the aphid population doubled every 11.4 days or 7.7 days, respectively). Clustering of the accessions into the different phenetic groups did not follow the geographical origin of the wheat genotypes or the species to which they belong. These results show that ancient diploid wheats, all characterized by the genome A, present considerable interest for plant breeding for resistance to S. avenae in modern wheat. The potential use of these strong and partial sources of resistance for introduction of a stable and durable form of resistance to S. avenae in wheat is discussed.  相似文献   
199.
The expression of p53 protein was investigated in eight formalin-fixed, paraffin-embedded conjunctival squamous cell carcinomas of five horses and one cow, dog and cat each by an immunohistochemical procedure in order to evaluate protein overexpression. Anti-human p53 protein mouse monoclonal antibodies known to be cross-reactive with p53 protein of the animal species examined were used. Positive p53 nuclear immunostaining was detected in five equine, one bovine and one feline cases. Conversely, no p53 immunostaining was found in the only canine case examined. These results demonstrate a frequent p53 overexpression in conjunctival squamous cell carcinoma that could be related to UV-induced mutations of the p53 tumor suppressor gene.  相似文献   
200.
The purpose of this study was to characterize the fecal microbiota of horses with acute and chronic diarrhea before and after fecal microbiota transplantation (FMT). Six client-owned horses with acute and chronic diarrhea received FMT from 2 healthy donor horses. Microbiota analysis using next-generation sequencing was performed on fecal samples collected before and 2 and 7 d after FMT. Signs of diarrhea improved in 4 horses, whereas the remaining 2 horses did not survive. There was a significant difference in the number of bacterial species between donors and recipients (P < 0.05). The Order Lactobacillales and the genera Lactobacillus, Intestinimonas, and Streptococcus were increased in the microbiota of diarrheic horses, and Saccharofermentans genus increased in healthy donors. The results suggest that FMT from the healthy donors was not effective over a 7-day period as it did not change the fecal microbiota of the diarrheic horses. Further research to improve the efficacy of FMT in horses is needed.  相似文献   
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