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排序方式: 共有370条查询结果,搜索用时 15 毫秒
1.
Andrzej Pedryc Szabolcs Ruthner Rita Hermán Boris Krska Attila Hegedűs Júlia Halász 《Scientia Horticulturae》2009
Eight polymorphic simple sequence repeat (SSR) markers located in the G1 linkage group of apricot (Prunus armeniaca L.) were previously developed and evaluated in a small set of cultivars. Those primers were used for studying variability in 77 apricot cultivars belonging to five different geographical groups, such as Chinese, Asian (Irano-Caucasian and Central Asian), North American, Mediterranean and Western European as well as Middle European cultivars. Six of the markers were polymorphic and revealed a total of 71 alleles ranging from 5 (aprigms11) to 20 (aprigms1) alleles per locus with a mean value of 11.83 alleles per locus. In conclusion, the SSR loci located in the G1 linkage group show a level of polymorphism which is similar to loci dispersed throughout the entire genome. The total number of alleles and the number of unique alleles were the highest in Chinese apricots and the lowest in Middle European cultivars. Heterozygosity also showed a decrease from Asia and China to Middle Europe. No association could have been observed between any SSR markers tested and plum pox virus (PPV) resistant phenotype of cultivars. PPV resistant cultivars did not form a separate clade on the dendrogram obtained by UPGMA cluster analysis. Middle European and Chinese cultivars formed separate clusters while other genotypes formed smaller multiple sub-groups or scattered among different clusters. Our results support previous hypotheses on the origin of PPV resistance in North American apricots. The allele data was also presented in a form that allowed the easy observation of allele frequencies in each geographical group at each locus. Using this data field, differences and similarities between cultivar groups can be easily assessed. The analysis demonstrated the links between the North American and Mediterranean apricot germplasm and confirmed that the Chinese and Eastern European cultivars are distantly related. 相似文献
2.
Genes for resistance to powdery mildew in European barley cultivars registered in the Czech Republic from 2011 to 2015 下载免费PDF全文
Antonín Dreiseitl 《Plant Breeding》2017,136(3):351-356
Barley (Hordeum vulgare) is cultivated on 49.1 million hectares worldwide with 50.2% of the area located in Europe. Powdery mildew, caused by Blumeria graminis f. sp. hordei (Bgh), occurs wherever barley is grown. Cultivar resistance plays an important role in global barley production, especially in parts of Europe where high concentrations of both spring and winter types are grown. The aim of this report was to postulate specific resistance genes in barleys from nine European countries registered in the Czech Republic from 2011 to 2015. Thirty‐five spring cultivars and 27 winter barleys were tested with 56 diverse Bgh isolates. Twenty‐five known resistance genes were postulated, and unknown genes were detected in Sandra, Saturn and Zeppelin. Unidentified specific resistance genes were also present in winter hybrids Hobbit and Wootan. Spring cultivars Arthur and Francin consisted of three and two genotypes, respectively. Resistance gene mlo was present in 26 spring cultivars, and the proportion of cultivars with this gene increased from 62.9% in 2006–2010 to 75.7% in 2011–2015. The gene Mlp1 was identified for the first time in German winter cultivar Saturn. Five spring cultivars registered in Slovakia were included in the tests. All the cultivars that were tested contained one or more specific resistance genes to powdery mildew. Adaptability of the pathogen and possibilities for breeding winter barleys are discussed. 相似文献
3.
借助Ⅱ和Ⅲ型一氧化氮合成酶(NOS)特异性抗体对成年爪蛙(Xenopuslaevis)视网膜中含NOS的结构进行了免疫细胞化学定位研究。发现视杆和视锥细胞的视网膜杆、少数神经节细胞和无足细胞的细胞体均含有NOSⅡ免疫反应物质,缪勒细胞呈现强的NOSⅡ免疫反应性,外神经丛层的神经突起亦含强的NOSⅡ免疫反应性。在视网膜的细胞结构中,未见NOSⅢ免疫反应性。该结果暗示由NOSⅡ产生的一氧化氮可能参与视觉传导的调节。 相似文献
4.
Elena V. Girich Anton N. Yurchenko Olga F. Smetanina Phan Thi Hoai Trinh Ngo Thi Duy Ngoc Mikhail V. Pivkin Roman S. Popov Evgeny A. Pislyagin Ekaterina S. Menchinskaya Ekaterina A. Chingizova Shamil S. Afiyatullov Ekaterina A. Yurchenko 《Marine drugs》2020,18(12)
Low molecular weight secondary metabolites of marine fungi Aspergillus flocculosus, Aspergillus terreus and Penicillium sp. from Van Phong and Nha Trang Bays (Vietnam) were studied and a number of polyketides, bis-indole quinones and terpenoids were isolated. The structures of the isolated compounds were determined by 1D and 2D NMR and HR-ESI-MS techniques. Stereochemistry of some compounds was established based on ECD data. A chemical structure of asterriquinone F (6) was thoroughly described for the first time. Anthraquinone (13) was firstly obtained from a natural source. Neuroprotective influences of the isolated compounds against 6-OHDA, paraquat and rotenone toxicity were investigated. 4-Hydroxyscytalone (1), 4-hydroxy-6-dehydroxyscytalone (2) and demethylcitreoviranol (3) have shown significant increasing of paraquat- and rotenone-treated Neuro-2a cell viability and anti-ROS activity. 相似文献
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Anton T. Ibbotson William D. Riley William R.C. Beaumont Alastair C. Cook Mark J. Ives Adrian C. Pinder Luke J. Scott 《Ecology of Freshwater Fish》2013,22(1):73-81
Over 3 years, 32,444 age‐0 group Atlantic salmon (Salmo salar) parr tagged with passive integrated transponder tags throughout the River Frome catchment were assigned to one of three groups, nonmigrants, autumn migrants and spring smolts, depending on the detection and the timing of detection at downstream tag readers (situated 8.6 km above the tidal limit). We examined the effect of density at the time of tagging (n·m?2), distance upstream from the tidal limit (km), fish length (mm), Fulton condition index, habitat type (divided into two types, main river and carrier), days after 1 September that each fish was tagged and year (replication) on the proportions of fish in each of the migration groups. Distance upstream from tidal limit was strongly negatively related to the proportion of autumn migrants and positively related to the proportion of spring smolts. Nonmigrants had a lower average body size than migrants, although there were no differences in the sizes of autumn migrants and spring smolts in September prior to migration. Fish density had no effect on migration strategy. A lower proportion of fish migrated as autumn migrants from the smaller carrier habitats than the main river channel. There is some evidence that those parr destined to become autumn migrants underwent a lower mortality rate during September before tagging than those destined to become spring migrants indicating possible physiological or behavioural differences between these two groups of fish at that time. More research into the factors responsible for initiating the autumn migration is required. 相似文献
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9.
Joeke Nijboer Marcus Clauss Moniek Olsthoorn Wendy Noordermeer Tjalling R Huisman Celine Verheyen Jan van der Kuilen W Streich Jürgen Anton C Beynen 《Journal of zoo and wildlife medicine》2006,37(3):366-372
A high intake of easily fermentable carbohydrates and a low intake of fiber material are generally regarded as major factors affecting the health of captive langurs. The effect on fecal consistency of excluding fruits and vegetables from the diet was evaluated in Javan langurs (Trachypithecus auratus auratus). Cross-over trials were carried out at Rotterdam Zoo and at the Apenheul Zoo, The Netherlands. During the first and third dietary period, the langurs were fed their usual diet, which contained fruits, vegetables, langur pellets, and browse. During the second period, the vegetables and fruits were excluded from the diet and the diet essentially consisted of pellets and browse. Feces consistency was scored using a fecal score chart developed for langurs. During the second feeding period the feces consistency improved significantly in animals at both zoos. Across all trials, a firmer feces consistency was correlated with an increase in dietary cell wall (measured as neutral detergent fiber) and a decrease in dietary water. It is suggested that the combined decrease in the intake of soluble sugars, the increase of fiber intake, and a lower amount of dietary water in the diet resulted in more solid stools. The results indicate that a dietary neutral detergent fiber content of approximately 46% in dry matter will result in a feces consistency indicative of undisturbed gut function. 相似文献
10.
Die Steigerung der naturalen Erträge unserer Kulturpflanzen ist gegenwärtig kein wissenschaftlicher Arbeitsgegenstand der produktionsorientierten landwirtschaftlichen Forschung. Es bestehen häufig Bedenken, daß mit einer zunehmenden Ertragshöhe unerwünschte Wirkungen auf die Umwelt verbunden sind. An ausgewählten Beispielen wird dargelegt, daß es zum einen nicht möglich ist, aus der Ertragshöhe oder den Ertragssteigerungen pauschal auf negative Umweltwirkungen der ackerbaulichen Produktion zu schließen. Zudem wird diskutiert, welche Bedeutung die Steigerung der Erträge von Kulturpflanzen für die Sicherung der technologischen, aber auch der ökologischen Ansprüche hat. Ein Rückgang der Forschungs‐ und Publikationsleistungen zu Anbauverfahren bzw. dem Ertragsmanagement wird für die letzten Jahre dargelegt und dessen Bedeutung für die wissenschaftlichen Arbeiten der landwirtschaftlichen Produktion erörtert. 相似文献