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Plant mating systems are known to influence population genetic structure because pollen and seed dispersal are often spatially restricted. However, the reciprocal outcomes of population structure on the dynamics of polymorphic mating systems have received little attention. In gynodioecious sea beet (Beta vulgaris ssp. maritima), three sexual types co‐occur: females carrying a cytoplasmic male sterility (CMS) gene, hermaphrodites carrying a non‐CMS cytoplasm and restored hermaphrodites that carry CMS genes and nuclear restorer alleles. This study investigated the effects of fine‐scale genetic structure on male reproductive success of the two hermaphroditic forms. Our study population was strongly structured and characterized by contrasting local sex‐ratios. Pollen flow was constrained over short distances and depended on local plant density. Interestingly, restored hermaphrodites sired significantly more seedlings than non‐CMS hermaphrodites, despite the previous observation that the former produce pollen of lower quality than the latter. This result was explained by the higher frequency of females in the local vicinity of restored (CMS) hermaphrodites as compared to non‐CMS hermaphrodites. Population structure thus strongly influences individual fitness and may locally counteract the expected effects of selection, suggesting that understanding fine scale population processes is central to predicting the evolution of gender polymorphism in angiosperms.  相似文献   
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Summary The nutrient status of soybean seeds fermented to daddawa has been evaluated by chemical analyses. Soybean daddawa is nutritionally rich, containing 45.91% crude protein, 33.44% lipid, 13.69% carbohydrate and 3.60% crude fibre. The amino acids lysine, threonine, valine, methionine, isoleucine, leucine, tyrosine, phenylalanine, histidine, arginine, asparagine, serine, glutamic acid, proline and glycine were present in unfermented and fermented bean samples. The amounts of most of the amino acids including methionine increased however, when the beans were fermented to daddawa.
Resumen El valor nutritivo de semillas de soja fermentadas para elaborar daddawa se ha evaluado mediante analísis químicos. El daddawa obtenido a partir de soja es muy rico en nutrientes ya que contiene: proteina cruda: 45.91%, lípidos: 33.44%, carbohidratos: 13.69%, fibra 3.60%. Los siguientes aminoácidos se encontraron en muestras fermentadas y no fermentadas de semillas: lisina, treonina, valina, metionina, isoleucina, leucina, tirosina, fenilalanina, histidina, arginina, asparagina, serina, ácido glutámico, prolina y glicina. Las cantidades de estos aminoácidos, incluyendo la metionina, eran, sin embargo, superiores cuando la soja estaba fermentada formando daddawa.

Résumé La valeur nutritive du daddawa (graines de soja fermentées) a été évaluée par analyse chimique. Nutritionnellement riche, le daddawa contient 45,91% de protéine brute, 33,44% de lipides, 13,69% de carbohydrates et 3,60% de fibres brutes. Dans les graines fermentées et nonfermentées, on a mis en évidence les amino-acides suivants: lysine, thréonine, valine, méthionine, isoleucine, leucine, tyrosine, phénylalanine, histidine, arginine, asparagine, sérine, acide glutamique, proline et glycine. Cependant, les teneurs de la plupart de ces amino-acides, y compris la méthionine, sont plus élevées après fermentation du soja en daddawa.
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14-3-3 proteins are known to play a pivotal role in cell survival, apoptosis and signal transduction. The 14-3-3ζ isoform has been cloned and characterized from many eukaryotic organisms, including the fruit fly and silkworm. However, no study on mosquito 14-3-3 has been reported to date. In an attempt to investigate the function of 14-3-3 in midgut epithelial cells undergoing apoptosis, a cDNA library was generated from the malaria vector, Anopheles sinensis , which was treated with apoptosis-inducing Actinomycin-D. We were able to identify and obtain A. sinensis 14-3-3ζ cDNA ( Ansi14-3-3ζ ) from expressed sequence tags (EST) analysis after conducting massive sequencing of the A. sinensis cDNA library. Ansi14-3-3ζ has very high homology to 14-3-3 homologs of various insects, such as Anopheles gambiae (100%), Aedes aegypti (100%), Drosophila melanogaster (96%), Bombyx mori (93%), Apis mellifera (93%) and Mus musculus (81%), indicating that mosquito 14-3-3ζ is a highly conserved gene in diverse organisms. Analysis of temporal expression patterns showed that Ansi14-3-3ζ mRNA is highly expressed in egg, early pupae and adult stages and is also expressed, although at low levels, in fourth instar larvae and late pupae. In response to two immune elicitors (lipopolysaccharide and laminarin), no striking induction of 14-3-3ζ mRNA was observed in A. sinensis . Further studies of the precise biological function, inducibility and subcellular distribution of 14-3-3ζ are required in Plasmodium invasion-induced apoptotic midgut cells in A. sinensis in the context of the Time Bomb model.  相似文献   
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Apolipophorin‐III is known to play a role in transporting lipids in insects, and much attention has been paid to lepidopteran insects' apolipophorin. Thus, we were interested in examining the effects of blood‐meal on the expression pattern of apolipophorin‐III in mosquitoes. This led us to clone and partially characterize the full‐length cDNA of apoLp‐III (AnsiApoLp‐III) from Anopheles sinensis. Analysis of AnsiApoLp‐III cDNA shows that the 728‐bp sequence has a 582‐bp protein‐coding region with 94 bp of putative 5′ untranslated region and 152 bp of 3′ untranslated region. The deduced amino acid sequence begins with a methionine codon at position 95 and extends to position 674, encompassing a polypeptide of 193 amino acids. AnsiApoLp‐III has the highest identity (63%) to Culex quinquefasciatus apoLp‐III. Temporal expression pattern analysis shows that although AnsiApoLp‐III was expressed at all developmental stages, it was highly detected at egg and adult stages in the female mosquitoes. In addition, we found out that AnsiApoLp‐III was induced in An. sinensis adult females after uptaking a blood‐meal. Spatial expression patterns of AnsiApoLp‐III shows that AnsiApoLp‐III mRNA was strongly induced at day 1 and gradually decreased from day 1 to day 4 in the ovaries. Most interestingly, AnsiApoLp‐III mRNA in the Malpighian tubule was strongly induced at day 1, decreased during days 1–3, and then became elevated again at day 4. These data suggest that blood‐meal influences AnsiApoLp‐III mRNA induction in ovaries and Malpighian tubules. It remains to further elucidate the biological roles of AnsiApoLp‐III in these organs.  相似文献   
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The identification of northern and southern components in different vertebrate species led researchers to accept a two‐component hypothesis for the Brazilian Atlantic forest (BAF). Nevertheless, neither a formal proposal nor a meta‐analysis to confirm this coincidence was ever made. Our main objective here was therefore to systematically test in how many vertebrate components the BAF could be divided by analysing existing empirical data. We used two approaches: (1) mapping and comparing the proposed areas of vertebrate endemism in the BAF and (2) analysing studies mentioning spatial subdivisions in distinct forest‐dependent vertebrates within the biome, by the use of panbiogeography. The four large‐scale endemism area components together with the six small‐scale panbiogeographical ones allowed the definition of three BAF greater regions, subdivided into nine vertebrate components, latitudinally and longitudinally organized. Empirical time estimates of the diversification events within the BAF were also reviewed. Diversification of these vertebrates occurred not only in the Pleistocene but also throughout the Miocene. Our results confirm the BAF's complex history, both in space and time. We propose that future research should be small‐scale and focused in the vertebrate components identified herein. Given the BAF's heterogeneity, studying via sections will be much more useful in identifying the BAF's historical biogeography. © 2012 The Linnean Society of London, Biological Journal of the Linnean Society, 2012, ??, ??–??.  相似文献   
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为重新分析韩国大麝鼩种群与相邻的俄罗斯远东种群之间的遗传分化情况,我们获得9 条来自韩国4 个地点和俄罗斯3 个地点的大麝鼩线粒体细胞色素b 基因(Cyt b)全序列,并将其与来自GenBank 的4 条Cyt b 全序列和4 条Cyt b 部分序列进行比较。结果发现韩国的大麝鼩并非只有一种基因型,因此,在利用Cyt b 部分序列进行种群遗传学分析时需格外注意。基于Cyt b 全序列分析,发现韩国的大麝鼩与俄罗斯远东地区的大麝鼩之间存在1.08% 的平均JC 距离和7 个位点的差异,推测韩国的大麝鼩与俄罗斯远东地区的大麝鼩在包括末次冰盛期在内的很长时期都没有进行过遗传交流。目前的测序结果不支持当前认为大麝鼩为单系群的亚种分类理论,支持韩国大麝鼩是C. l. thomasi 亚种的分类理论,但还需进一步对中国东北地区的样品进行测序分析后才能最终确认。  相似文献   
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1. Although theory suggests that intraguild predation destabilises food webs and may result in exclusion of species, empirical observations of food webs reveal that it is a common interaction. It has been proposed that habitat structure reduces the interaction strength of intraguild predation, thus facilitating the coexistence of species. 2. This was tested using acarodomatia, tiny structures on plant leaves, and predatory mites, which usually reside in these domatia. Sweet pepper plants (Capsicum annuum L.) were used, which possess domatia consisting of tufts of hair, and coffee plants (Coffea arabica L.) with pit‐shaped domatia. 3. On sweet pepper, the predatory mites Neoseiulus cucumeris Oudemans and Iphiseius degenerans Berl. feed on each other's juveniles. Larvae of each of the species were therefore used as intraguild prey with adult females of the other species as intraguild predators. On coffee, a similar set‐up was used, with larvae and adult females of Amblyseius herbicolus Chant and Iphiseiodes zuluagai Denmark & Muma as intraguild prey and intraguild predators, respectively. 4. Domatia on detached, isolated sweet pepper and coffee leaves were either closed with glue or left open, after which larvae and adult predators were released. As a control, larvae were released on leaves with open or closed domatia without an adult predator. 5. Survival of larvae was high in the absence of the adult (intraguild) predator. In the presence of the intraguild predator, survival was significantly higher on leaves with open domatia than on leaves with closed domatia. 6. This shows that even such tiny structures as plant domatia may significantly affect the interaction strength of intraguild predation.  相似文献   
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Abstract Understanding the factors that affect plant species distribution and coexistence in areas with high plant species diversity is a challenge for ecologists. According to some authors, species occupy specific niches, but for others, species coexistence and geographical distribution patterns are random. Floristic composition of the family Leguminosae was studied on moist and dry slopes of the Baturité mountains in semi‐arid northeastern Brazil and was compared with findings for other plant formations elsewhere in Brazil. Substantial floristic differences were found between the moist windward and dry leeward slopes of the Baturité mountains despite their close geographical proximity. The leeward slope was slightly more diverse than the windward slope. Similarity analyses showed that the windward face is floristically allied to the Amazon forest, whereas the leeward slope is similar to other dry‐area formations of northeastern Brazil, such as thorny woodland (caatinga) and seasonal forests. The strong floristic differences that were observed between the windward and leeward slopes corroborate the theory of ecological niche conservatism, which holds that species occurrence is closely linked to environmental factors, such as temperature and precipitation.  相似文献   
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