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141.
BACKGROUND: The history of domestication of artichoke and leafy cardoon is not yet fully understood and when and where it occurred remains unknown. Evidence supports the hypothesis that wild cardoon is the wild progenitor of both these crops. Selection for large, non-spiny heads resulted in artichoke and selection for non-spiny, large stalked tender leaves resulted in leafy cardoon. The two crops differ in their reproductive system: artichoke is mostly vegetatively propagated and perennial, while leafy cardoon is seed propagated and mostly grown as an annual plant. Here, new trends in artichoke cultivation are analysed, while the consequences of these tendencies on the conservation of artichoke genetic resources are highlighted. SCOPE: The historical and artistic records, together with recent literature on genetics and biosystematics, are examined with the aim of achieving a better understanding of the present-day knowledge on the domestication of these two crops. CONCLUSIONS: Historical, linguistic and artistic records are consistent with genetic and biosystematic data and indicate that the domestication of artichoke and cardoon diverged at different times and in different places. Apparently, artichoke was domesticated in Roman times, possibly in Sicily, and spread by the Arabs during early Middle Ages. The cardoon was probably domesticated in the western Mediterranean in a later period.  相似文献   
142.
选择我国狂犬病高发地区(湖南、贵州)、低发地区(江苏、武汉)和无狂犬病报告地区(沈阳)等三种不同类型的地区,开展针对家养犬、猫和啮齿类动物,以及蝙蝠等野生动物的狂犬病病毒带毒率的流行病学调查,对分离到的病毒株在抗原型别、基因变异以及与现行疫苗是否匹配等方面进行分析、比较研究。结果显示:我国狂犬病的主要宿主动物为犬,捕获犬总带毒率为2.56%;犬中狂犬病病毒的监测点最高阳性检出率达到20.0%;啮齿类动物及蝙蝠等野生动物在本次研究未检测到狂犬病病毒。我国自主研制成功的以aG株和CTN株为毒种的现行人用狂犬病疫苗,经应用研究发现,CTN株的糖蛋白基因与本研究分离到的街毒核酸序列更接近。为进一步评价现行疫苗的有效性,在5个观察点分别以aG株和CTN株毒种生产的疫苗接种两组人群(每组各约50人),结果显示均未出现中、强度反应,疫苗免疫后第7d和14d产生的中和抗体分别达到0.49IU/mL~0.52IU/mL和6.7IU/mL~7.53IU/mL;抗体阳转率分别为45.1%~47.9%和100%,表明这些疫苗具有良好的安全性和保护效果。  相似文献   
143.
目的:测定掌握莱芜灰树花野生菌株的生物学特性,为其开发利用提供科学依据。方法:采用组织分离法和菌丝尖端纯化技术分离纯化菌种;采用生长速率法测定其生长适宜条件。结果:该野生菌株的菌丝体生长的最适温度为28℃;最适pH值为5.5;在被测的11种碳源和7种氮源中,最佳碳源为甘露糖,最佳氮源为(NH4)2SO4;KH2PO4对菌丝体的生长具有明显的促进作用,促进效果达223.64%;培养料最适含水量为65%;子实体生长发育温度24~30℃,平均转化率为66.37%。结论:莱芜灰树花野生菌株为转化率中等的高温型株系。  相似文献   
144.
广东野生大型真菌资源及其开发利用前景展望   总被引:1,自引:1,他引:0  
广东野生大型真菌物种资源丰富,据初步统计已知种类有1185种,占中国大型真菌的30%左右,其中有不少的本地特有种,野生食用菌和药用菌有300种,具有重要经济开发潜力的有50种,毒蘑菇有110多种,有广泛的开发利用价值。根据广东野生大型真菌资源特色,提出了有效保护和可持续利用的相关措施。  相似文献   
145.
野生植物狮子尾营养成分的研究及应用   总被引:1,自引:0,他引:1  
对野生植物狮子尾的营养成分进行了分析,结果表明,狮子尾中含有多种营养成分,丰富的矿质元素和维生素及β-胡萝卜素。狮子尾中至少含有17种氨基酸。旨在为开发利用植物资源提供科学依据。  相似文献   
146.
甘肃省药用植物秦艽野生资源现状及开发利用   总被引:2,自引:0,他引:2  
甘肃省是秦艽的原产地之一,蕴藏着丰富的野生资源.由于不合理的采挖利用,致使资源遭到破坏.对甘肃省秦艽野生资源的种类、分布及生态环境特征、生长情况、采挖与收购现状进行了阐述,并提出了合理开发利用的对策.  相似文献   
147.
The translocation of wild animals is a strategy frequently used in the conservation and management of natural populations. The aim of this study was to evaluate the impact of translocation (population supplementation) and habitat improvement on the abundance of European wild rabbit Oryctolagus cuniculus . We used eight open plots with different habitat treatments: two with increased shelter, two with increased food, two with increased shelter and food and two without habitat treatment (control plots). We translocated wild rabbits during 3 consecutive years, each year in four of the eight plots, with the remaining plots serving as control for the translocation treatment. Rabbit abundance (translocated plus native rabbits) was calculated by means of pellet counts, and the results were evaluated mainly by generalized linear mixed models. We found that rabbit abundance was determined primarily by habitat improvement. Rabbits were more abundant in treated than in control plots, and most abundant in the plots where food availability was increased. This effect persisted throughout the year. Translocation also increased abundance, but this effect was the strongest where shelter and food had also been improved and declined and disappeared after breeding. These findings suggest that the habitat is an important factor for rabbit abundance, with food availability being the prime factor regulating densities. Moreover, translocations on their own are only effective in the short term in situations in which factors limiting population growth (e.g. disease and predation) have not been corrected. Translocations should be carried out in conjunction with improvements in release habitat as rabbit densities will depend on the maximum carrying capacity of the habitat.  相似文献   
148.
After a decade of transgenic crop production, the dynamics of gene introgression into wild relatives remain unclear. Taking an ecological genetics approach to investigating fitness in crop-wild hybrid zones, we uncovered both conditions and characteristics that may promote introgression. We compared diverse crop-wild hybrid genotypes relative to wild Helianthus annuus under one benign and three stressful agricultural environments. Whereas relative fitness of crop-wild hybrids averaged 0.25 under benign conditions, with herbicide application or competition it reached 0.45 and was more variable. In some instances, hybrid fitness matched wild fitness (approximately 1). Thus, wild populations under agronomic stress may be more susceptible to introgression. Although 'domestication' traits are typically considered unlikely to persist in wild populations, we found some (e.g. rapid growth and early flowering) that may enhance hybrid fitness, especially in stressful environments. Rigorous assessment of how particular genotypes, phenotypes, and environments affect introgression will improve risk assessment for transgenic crops.  相似文献   
149.
Leptospirosis is a worldwide zoonosis. The importance of urban leptospirosis is recognized in Japan: urban rats carry pathogenic leptospires and people acquire these pathogens through contact with surface water or soil contaminated by the urine of the infected animals. To determine the current Leptospira carriage rate in urban rats, 29 wild rats were trapped in the central area of Fukuoka and strains isolated from their kidneys and urine analyzed. When semi‐solid Korthof's medium containing 0.1% agar was used for isolation, 72.2% and 30.8% of the kidney and urine cultures, respectively, were found to be Leptospira‐positive. The isolates belonged to Leptospira interrogans, and were classified into two groups (serogroups Pomona and Icterohaemorrhagiae) based on the results of gyrB sequence analysis and microscopic agglutination testing (MAT). Strains belonging to serogroup Icterohemorrhagiae grew well in liquid medium. On the other hand, serogroup Pomona isolates multiplied very little in liquid medium, but did grow in a semi‐solid medium. Although strains belonging to serogroup Pomona have not been recognized as native to Japan, this strain may be widely distributed in urban rats. Representative strains from each group were found to be highly pathogenic to hamsters. Our findings should serve as a warning that it is still possible to become infected with leptospires from wild rats living in inner cities of Japan. Furthermore, the use of semi‐solid medium for culture will improve the isolation rate of leptospires from the kidneys of wild rats.  相似文献   
150.
Examining the relevance of ‘animal personality’ involves linking consistent among- and within-individual behavioural variation to fitness in the wild. Studies aiming to do this typically assay personality in captivity and rely on the assumption that measures of traits in the laboratory reflect their expression in nature. We examined this rarely tested assumption by comparing laboratory and field measurements of the behaviour of wild field crickets (Gryllus campestris) by continuously monitoring individual behaviour in nature, and repeatedly capturing the same individuals and measuring their behaviour in captivity. We focused on three traits that are frequently examined in personality studies: shyness, activity and exploration. All of them showed repeatability in the laboratory. Laboratory activity and exploration predicted the expression of their equivalent behaviours in the wild, but shyness did not. Traits in the wild were predictably influenced by environmental factors such as temperature and sunlight, but only activity showed appreciable within-individual repeatability. This suggests that some behaviours typically studied as personality traits can be accurately assayed in captivity, but the expression of others may be highly context-specific. Our results highlight the importance of validating the relevance of laboratory behavioural assays to analogous traits measured in the wild.  相似文献   
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