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Fjellheim S Rognli OA 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2005,111(4):640-650
Genetic diversity and relatedness were studied in 30 Norwegian local populations of meadow fescue (Festuca pratensis Huds.) using amplified fragment length polymorphism (AFLP) markers. The populations were also compared with 13 Nordic meadow fescue cultivars in order to analyse the distribution of variation in local populations and cultivars and to elucidate relationships between local populations and cultivars. Analysis of molecular variance (amova) analysis showed that most of the variation was present within populations and that little variation was found between local populations and cultivars. Separate amova analyses of local populations and cultivars revealed a higher level of variation within registered cultivars than within local populations. A cluster analysis based on corrected average pairwise differences between populations showed that the populations could be divided into three clusters, of which one also contained the cultivars. These results were supported by principal coordinates analysis. The results indicate that the Norwegian meadow fescue has a narrow genetic basis and that the local populations in Norway can be divided into three groups following the most probable routes of introduction of the species into Norway. The inland populations are closely related to the cultivars and have most probably been established as a result of migration from sown meadows. The western and southern populations probably originate from human activity—for example, trade—to the coastal western and northern parts of the country and to the central parts of southern Norway. 相似文献
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We report a case of mental retardation associated with multiple congenital anomalies suggesting an F.G. syndrome. We discuss problems concerning genetic counselling and the management of future pregnancies. Unfortunately, no concrete strategy, concerning prenatal diagnosis, can be proposed. 相似文献
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F. J. J.Buytendijk died on October 21st 1974 at the age of 87. His important contribution to the study of animal behaviour is analyzed here in relation to the historical development of animal psychology and ethology. The detailed study of his scientific production suggests, according to the authors, that some important findings, although largely not paid attention to in present-day literature, are akin to the conceptual and methodological evolution of comparative ethology. 相似文献
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ABSTRACT Festuca gamisansii subsp. aethaliae, endemic to the Isle of Elba (Tuscan Archipelago) is described. The morphological, anatomical, karyological, ecological and chorological characteristics of the species are given. The main characteristics distinguishing F. gamisansii subsp. aethaliae from F. gamisansii subsp. gamisansii occurring in Corsica are also summarized. 相似文献
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BRUNO FOGGI M. ELENA GHERARDI M. ADELE SIGNORINI GRAZIANO ROSSI PIERO BRUSCHI 《Botanical journal of the Linnean Society. Linnean Society of London》2006,151(2):239-258
According to current systematics, Festuca inops and F. gracilior are two distinct species. However, they are hardly distinguishable from each other on the basis of their morphological characters. Festuca inops is considered a diploid species endemic to Italy, while F. gracilior has a discontinuous distribution area, apparently related to chromosomal levels: diploid populations in Italy and south-east France, tetraploid populations in north-east Spain. The diploid populations of both taxa from Italy and south-east France are investigated in the present study. Nearly 1000 exsiccata were examined and morphometric analysis was carried out on macro- and micromorphological features of 119 specimens (including type-specimens) and on 20 natural populations (including loci classici ). All these data showed that the two species should be referred to a single taxon, for which the rank of species seems to be appropriate. This result is supported by karyological, ecological and chorological data and was confirmed by the results of ISSR analysis. According to nomenclatural rules, the legitimate name for the species is Festuca inops De Not. © 2006 The Linnean Society of London, Botanical Journal of the Linnean Society , 2006, 151 , 239–258. 相似文献
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著名生化学家莱洛伊尔L.F.(Leloir Luis F.)生于1906年,死于1987年12月4日。他的初期贡献之一且立即引人注目的,是发现了葡萄糖-1,6-二磷酸及葡萄糖-1,6-二磷酸作为磷酸葡萄糖变位酶辅助因子的作用。效仿于此,科里、萨瑟兰和帕斯特纳克一起,提出作为磷酸甘油酸变位酶的2,3双二磷酸甘油酸的类似作用的提议。在莱洛伊尔的重大发 相似文献
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Gerd Johansson 《Plant and Soil》1993,151(1):11-20
Distribution of net assimilated C in meadow fescue (Fectuca pratensi L.) was followed before and after cutting of the shoots. Plants were continuously labelled in a growth chamber with 14C-labelled CO2 in the atmosphere from seedling to cutting and with 13C-labelled CO2 in the atmosphere during regrowth after the cutting. Labelled C, both 14C and 13C, was determined at the end of the two growth periods in shoots, crowns, roots, soil and rhizosphere respiration.
Distribution of net assimilated C followed almost the same pattern at the end of the two growth periods, i.e. at the end of
the 14C- and the 13C-labelling periods. Shoots retained 71–73% of net assimilated C while 9% was detected in the roots and 11–14% was released
from the roots, determined as labelled C in soil and as rhizosphere respiration.
At the end of the 2nd growth period, after cutting and regrowth, 21% of the residual plant 14C at cutting (14C in crowns and roots) was found in the new shoot biomass. A minor part of the residual plant 14C, 12%, was lost from the plants. The decreases in 14C in crowns and roots during the regrowth period suggest that 14C in both crowns and roots was translocated to new shoot tissue.
Approximately half of the total root C at the end of the regrowth period after cutting was 13C-labelled C and thus represents new root growth. Root death after cutting could not be determined in this experiment, since
the decline in root 14C during the regrowth period may also be assigned to root respiration, root exudation and translocation to the shoots. ei]{gnH}{fnLambers}
ei]{gnA C}{fnBorstlap} 相似文献
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将含有DREB1A基因的表达载体,通过基因枪法转化草地早熟禾的胚性愈伤组织,探讨了金粉沉淀剂、金粉直径等因素对转化的影响,同时通过不同浓度潮霉素(Hygromycin,简称Hy)对未转化愈伤组织的筛选,获得最佳筛选浓度。结果表明,适合于草地早熟禾基因枪轰击的条件为:Ca(NO3)2+PEG4000包被质粒DNA;1μm金粉作为质粒DNA的载体;合适的轰击高度为6cm、轰击次数为1次、无渗透处理。采用Hy作为草地早熟禾转基因植株抗生素筛选标记时,Baron品种愈伤组织继代的临界筛选浓度为100mg/L。 相似文献
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基因枪转化法获得草地早熟禾(Poa pratensis L.)转基因植株 总被引:7,自引:0,他引:7
将与植物抗旱耐盐有关的BADH-CMO双基因、CMO单基因、DREB1A单基因三种外源基因通过基因枪法分别轰击草地早熟禾的胚性愈伤组织,经过一系列筛选与再生培养,得到了抗性植株。经过PCR、Southern杂交分析检测,证明BADH-CMO双基因、CMO基因、DREB1A基因已经成功整合到草地早熟禾的植物基因组中。 相似文献
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Pedro E. Gundel Cyd E. Hamilton Charlotte E. Seal Marjo Helander María Alejandra Martínez-Ghersa Claudio M. Ghersa Beatriz R. Vázquez de Aldana Iñigo Zabalgogeazcoa Kari Saikkonen 《Symbiosis (Philadelphia, Pa.)》2012,58(1-3):73-80
Vertically transmitted fungal endophytes can be beneficial for host grasses. While the alkaloid-mediated mechanism for herbivore resistance has been widely studied, underlying physiological mechanisms for increased tolerance to abiotic stress remain scarcely explored. In this study we used three maternal lines of perennial grass Festuca rubra to examine the role of antioxidants in endophyte-mediated effects on seed viability over long-term storage. Uncolonized plants (E?) were generated by removing the endophyte from ramets of naturally endophyte-colonized (E+) plants. The E?+ and E? ramets were planted in a common garden in Salamanca, Spain. Seeds produced in 2009, 2010 and 2011 were harvested at maturity, dried and stored at 10 °C until 2011 when we tested seed and endophyte viability, and measured antioxidants. Seed viability and α-tocopherol antioxidant were negatively affected by the endophyte in two maternal lines. In these same lines, the endophyte viability was lowest at the longest storage time. In the maternal line that showed the highest negative effect of endophyte on seed viability, the pattern of glutathione was opposite to that observed for tocopherols since it was higher for E?+ than for E? seeds. In all maternal lines, the glutathione half-cell reduction potential (EGSSG/2GSH) and % glutathione disulphide (GSSG) increased with storage time but there was no clear pattern associated with endophyte symbiosis. Whether these parameters are good predictors of seed and endophyte longevity in storage and natural conditions should be further explored. 相似文献
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Genetic and morphological differentiation in Populus nigra L.: isolation by colonization or isolation by adaptation?
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Identifying processes underlying the genetic and morphological differences among populations is a central question of evolutionary biology. Forest trees typically contain high levels of neutral genetic variation, and genetic differences are often correlated with geographic distance between populations [isolation by distance (IBD)] or are due to historic vicariance events [isolation by colonization (IBC)]. In contrast, morphological differences are largely due to local adaptation. Here, we examined genetic (microsatellite) and morphological (from a common garden experiment) variation in Populus nigra L., European black poplar, collected from 13 sites across western Europe and grown in a common garden in Belgium. Significant genetic differentiation was observed, with populations from France displaying greater admixture than the distinct Spanish and central European gene pools, consistent with previously described glacial refugia (IBC). Many quantitative traits displayed a bimodal distribution, approximately corresponding to small‐leaf and large‐leaf ecotypes. Examination of nine climatic variables revealed the sampling locations to have diverse climates, and although the correlation between morphological and climatic differences was significant, the pattern was not consistent with strict local adaptation. Partial Mantel tests based on multivariate summary statistics identified significant residual correlation in comparisons of small‐leaf to large‐leaf ecotypes, and within the small‐leaf samples, but not within large‐leaf ecotypes, indicating that variation within the small‐leaf morphotype in particular may be adaptive. Some small‐leaf populations experience climates very similar to those in large‐leaf sites. We conclude that adaptive differentiation and persistent IBC acted in combination to produce the genetic and morphological patterns observed in P. nigra. 相似文献
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Anne E. Storey 《Ethology : formerly Zeitschrift fur Tierpsychologie》1994,98(2):89-100
I investigated alternative hypotheses concerning the functions of pre-implantation male-induced pregnancy disruption in meadow voles. Disruptions may be viewed as: 1. Postcopulatory male competition; 2. A mechanism for postcopulatory mate choice by females; and 3. A means of benefitting females by terminating investment in litters that may be harmed by new males. Female voles were paired with a second male 3 d after mating with their first mate. Behavioural interactions between the female and each male were compared for females that disrupted or retained the pregnancy sired by the first male. Whether they were the females' first or second mates, males siring litters showed similar high levels of approach and moderately high aggression, behaviour that differed from the females' other mates. Disrupted females huddled sooner with their second mates than females that retained their original pregnancies, and females tended to approach males that approached them. These results suggest that females influence whether a disruption occurs by the amount of contact they initiate with the second male, and thus pregnancy disruption may facilitate postcopulatory mate choice by females. This pre-implantation disruption did not enhance female reproductive success: pup survival was the same whether or not a disruption occurred, and males living with pups they had sired (after a disruption) spent as much time with them as males with unrelated pups (females did not disrupt). 相似文献
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