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41.
42.
云南及周边地区野菜和野果资源 总被引:2,自引:0,他引:2
本文是根据“云南及周边地区生物资源调查”项目的系统调查结果汇总的。云南及周边地区野菜和野果资源,指的是该地区栽培蔬菜、果树及其野生近缘植物之外的可食的野菜和野果。云南及周边地区是多个少数民族聚居区,各少数民族都有采食野菜和野果的习俗,并且在长期采食野菜和野果中,积累了丰富的食用方法。本文介绍云南及周边地区的野菜和野果,旨在为深入研究和开发利用这些资源,并为国家制定野生植物保护有关政策提供基础数据和信息。 相似文献
43.
云南及周边地区农作物野生近缘植物 总被引:1,自引:0,他引:1
高爱农 《植物遗传资源学报》2013,14(2):193-201
"云南及周边地区生物资源调查"项目是国家科技部基础性工作专项,现已通过国家验收。云南及周边地区是低纬度高海拔地区,也是我国少数民族聚居区,农作物的种类和物种多样性及遗传多样性都十分丰富,并且孕育了丰富的农作物野生近缘植物。本文仅介绍云南及周边地区粮食作物、经济作物、蔬菜作物、果树作物的野生近缘植物,旨在为这些野生近缘植物的研究和开发,制定国家野生植物多样性保护政策提供基础数据和相关信息。 相似文献
44.
Rachel Wooliver Silas B. Tittes Seema N. Sheth 《Evolution; international journal of organic evolution》2020,74(8):1699-1710
Evolutionary rescue can prevent populations from declining under climate change, and should be more likely at high-latitude, “leading” edges of species’ ranges due to greater temperature anomalies and gene flow from warm-adapted populations. Using a resurrection study with seeds collected before and after a 7-year period of record warming, we tested for thermal adaptation in the scarlet monkeyflower Mimulus cardinalis. We grew ancestors and descendants from northern-edge, central, and southern-edge populations across eight temperatures. Despite recent climate anomalies, populations showed limited evolution of thermal performance curves. However, one southern population evolved a narrower thermal performance breadth by 1.31°C, which matches the direction and magnitude of the average decrease in seasonality experienced. Consistent with the climate variability hypothesis, thermal performance breadth increased with temperature seasonality across the species’ geographic range. Inconsistent with performance trade-offs between low and high temperatures across populations, we did not detect a positive relationship between thermal optimum and mean temperature. These findings fail to support the hypothesis that evolutionary response to climate change is greatest at the leading edge, and suggest that the evolution of thermal performance is unlikely to rescue most populations from the detrimental effects of rapidly changing climate. 相似文献
45.
Susanne von Bargen Rim Al Kubrusli Thomas Gaskin Stephanie Fürl Florian Hüttner Dag-Ragnar Blystad David G. Karlin Risto Jalkanen Carmen Büttner 《The Annals of applied biology》2020,176(3):210-222
Since Emaraviruses have been discovered in 2007 several new species were detected in a range of host plants. Five genome segments of a novel Emaravirus from mosaic-diseased Eurasian aspen (Populus tremula) have been completely determined. The monocistronic, segmented ssRNA genome of the virus shows a genome organisation typical for Emaraviruses encoding the viral RNA-dependent RNA polymerase (RdRP, 268.2 kDa) on RNA1 (7.1 kb), a glycoprotein precursor (GPP, 73.5 kDa) on RNA2 (2.3 kb), the viral nucleocapsid protein (N, 35.6 kDa) on RNA3 (1.6 kb), and a putative movement protein (MP, 41.0 kDa) on RNA4 (1.6 kb). The fifth identified genome segment (RNA5, 1.3 kb) encodes a protein of unknown function (P28, 28.1 kDa). We discovered that it is distantly related to proteins encoded by Emaraviruses, such as P4 of European mountain ash ringspot-associated virus. All proteins from this group contain a central hydrophobic region with a conserved secondary structure and a hydrophobic amino acid stretch, bordered by two highly conserved positions, thus clearly representing a new group of homologues of Emaraviruses. The virus identified in Eurasian aspen is closely associated with observed leaf symptoms, such as mottle, yellow blotching, variegation and chloroses along veins. All five viral RNAs were regularly detectable by RT-PCR in mosaic-diseased P. tremula in Norway, Finland and Sweden (Fennoscandia). Observed symptoms and testing of mosaic-diseased Eurasian aspen by virus-specific RT-PCR targeting RNA3 and RNA4 confirmed a wide geographic distribution of the virus in Fennoscandia. We could demonstrate that the mosaic-disease is graft-transmissible and confirmed that the virus is the causal agent by detection in symptomatic, graft-inoculated seedlings used as rootstocks as well as in the virus-infected scions used for graft-inoculation. Owing to these characteristics, the virus represents a novel species within the genus Emaravirus and was tentatively denominated aspen mosaic-associated virus. 相似文献
46.
Rocío Santos-Gally Rocío Pérez-Barrales Violeta I. Simón Juan Arroyo 《Annals of botany》2013,111(2):317-328
Background and Aims
Heterostyly and related style polymorphisms are suitable model systems to evaluate the importance of functional pollinators in the maintenance of population variability. In Narcissus papyraceus different functional pollinators, incompatibility system and flower morphology have been proposed to influence the maintenance of polymorphism through their effect on disassortative mating. Here a test is done to find out if the visitation rate of long- versus short-tongued pollinators correlates with the morph ratio and if the latter is related to other flower traits of the species across its main geographic range.Methods
Floral traits from 34 populations in the south-west of the Iberian Peninsula and in north-west Africa were measured, perianth variation was described and a comparison was made of allometric relationships between sex organs and floral tube. Correlations between pollinator guilds, stigma–anther separation of reciprocal morphs (our proxy for disassortative mating) and morph-ratio variation were analysed. Finally, the incompatibility system of the species in the northern and southern borders of its distribution are described.Key Results
Flowers from southern populations were significantly larger than flowers from centre and northern populations. The abundance of short-styled plants decreased gradually with increasing distance from the core region (the Strait of Gibraltar), with these disappearing only in the northern range. Although there was a significant difference in stigma–anther separation among populations, morph ratio was not associated with reciprocity or floral tube length. Long-style morph frequency increased with short-tongued pollinator visitation rate. Populations from both edges of the distribution range were self-incompatible and within- and between-morph compatible.Conclusions
The style morph ratio changed gradually, whereas perianth trait variation showed abrupt changes with two morphotypes across the range. The positive relationship between the visitation rate of short-tongued pollinators and the decrease of the short-style morph supports our initial hypothesis. The results highlight the importance of different pollinators in determining the presence of style polymorphism. 相似文献47.
Marine Pouget Sami Youssef Jérémy Migliore Marianick Juin Frédéric Médail Alex Baumel 《Annals of botany》2013,112(7):1409-1420
Background and Aims
Understanding the factors that shape variation in genetic diversity across the geographic ranges of species is an important challenge in the effort to conserve evolutionary processes sustaining biodiversity. The historical influences leading to a central–marginal organization of genetic diversity have been explored for species whose range is known to have expanded from refugia after glacial events. However, this question has rarely been addressed for Mediterranean endemic plants of azonal habitats such as rocky slopes or screes. In this context, this comprehensive study examined molecular and field data from Arenaria provincialis (Caryophyllaceae), a narrow endemic plant of south-eastern France.Methods
Across the whole geographic range, an investigation was made of whether high levels of abundance and genetic diversity (estimated from amplified fragment length polymorphism markers) are centrally distributed, to evaluate the relevance of the central–marginal hypothesis. Phylogeographic patterns inferred from chloroplast DNA (cpDNA) were used, applying Bayesian methods to test the influence of past biogeographic events. Multivariate analysis combining phylogeographic and ecological data was used to reveal the historical and ecological distinctiveness of populations.Key Results
Despite the narrow distribution of A. provincialis, a high level of nucleotide variation is found within cpDNA loci, supporting its persistence throughout the Pleistocene period. The area characterized by the highest genetic diversity is centrally located. Structured phylogeography and Bayesian factor analysis supported the hypothesis that the central area of the distribution was the source of both westward and eastward migrations, probably during arid periods of the Pleistocene, and more recently was a crossroads of backward migrations. By contrast, the two areas located today at the range limits are younger, have reduced genetic diversity and are marginal in the ecological gradients.Conclusions
This study highlights a case of strong population distinctiveness within a narrow range. Phylogeography sheds light on the historical role of the areas centrally situated in the distribution. The current range size and abundance patterns are not sufficient to predict the organization of genetic diversity. 相似文献48.
Hasan Hosseinzadeh Saeid Nasrollanejad Zahra Dordiani Vahid Jamshidnezhad 《Archives Of Phytopathology And Plant Protection》2013,46(16):1879-1883
Sharka disease is one of the most damaging diseases of fruit trees in the world, which is caused by Plum pox virus (PPV) that belongs to the genus Potyvirus in the family Potyviridae. Each year, this virus decreases the yield and causes substantial economic damages to its host plants worldwide. This virus is quarantined in Iran but in recent years, suspicious symptoms of the disease were observed in different grown areas, such as Golestan province. During 2010, 420 samples with mosaic, chlorosis, necrosis, ring pattern, blotches, etc. symptoms were collected from the gardens in Golestan province that included 100 samples from plum, 100 from peach and 240 from nectarine. These samples were evaluated using a double-antibody sandwich-ELISA (DAS-ELISA) method and a polyclonal antibody. The results of this survey indicated that among the total of 420 samples, none of them showed positive reaction in DAS-ELISA test. 相似文献
49.
50.
Julienne Ng Emily L. Landeen Ryane M. Logsdon Richard E. Glor 《Evolution; international journal of organic evolution》2013,67(2):573-582
Although the importance of signals involved in species recognition and sexual selection to speciation is widely recognized, the processes that underlie signal divergence are still a matter of debate. Several possible processes have been hypothesized, including genetic drift, arbitrary sexual selection, and adaptation to local signaling environments. We use comparative analyses to investigate whether the remarkable geographic variation of dewlap phenotype in a Hispaniolan trunk Anolis lizard (A. distichus) is a result of adaptive signal divergence to heterogeneous environments. We recover a repeated pattern of divergence in A. distichus dewlap color, pattern, and size with environmental variation across Hispaniola. These results are aligned with ecological models of signal divergence and provide strong evidence for dewlap adaptation to local signaling environments. We also find that A. distichus dewlaps vary with the environment in a different manner to other previously studied anoles, thus expanding upon previous predictions on the direction dewlaps will diverge in perceptual color space in response to the environment. 相似文献