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Публикации с 31 по 45 из 64 всего
Просмотров: 285 Rating Star
Генетическое разнообразие четырех фрагментов мтДНК и пяти микросателлитных локусов хпДНК изучалось в шести выборках лиственницы с территории СихотэАлинского биосферного заповед ника (Северное Приморье). Образцы отбирались по трансектам вдоль побережья Японского моря и с разным удалением в направл...ении от моря с целью выявить возможные видовые различия между ними. По ряду морфологических признаков некоторыми авторами предполагается, что в прибреж ной части заповедника произрастает лиственница ольгинская, заменяющаяся по мере продвиже ния в глубь материка на лиственницу Гмелина. По другим источникам северная граница ареала лиственницы ольгинской не достигает территории заповедника. Данные сравниваются с аналогич ными, полученными ранее в трех выборках с юга Приморья, в том числе из locus classicus листвен ницы ольгинской. У совокупности особей лиственниц (186 для мтДНК и 200 для хпДНК) были вы явлены пять митотипов и 52 хлоротипа. По результатам AMOVA доля изменчивости, которая при ходится на различия между всеми изученными выборками Larix по обоим типам маркеров, была выше: NST = 0.435 (мтДНК), RST = 0.041 (хпДНК), чем только между выборками внутри заповедни ка: NST = 0.079, RST = 0.005. Различий между группами “прибрежных” и “материковых” популяций не выявлено.
Подробнее Год издания: 2013
A revision of the Asian Pinus subsection Strobus (Pinaceae)
Просмотров: 327 Rating Star
The Asian taxa of Pinus subsect. Strobus are revised, based on available type and other authentic material as well as on extensive field studies, including populations at the type localities. P. fenzeliana is neotypified and transferred to P. subsect. Flexiles. Statistical evaluation of ample mater...ial revealed that the original description of P. kwangtungensis is based on heterogeneous material, including a population from Hainan Island, which is here distinguished and described as the new species P. orthophylla. The continental P. kwangtungensis s. str., which is morphologically very close to P. wangii, is recognized as a subspecies of the latter, besides subsp. varifolia. An isolated population inN Vietnam, near the Laotian border, hitherto also considered to belong to P. kwangtungensis, is described as the new species P. eremitana. The Japanese P. parviflora, with two subspecies, is found to be closely related to P. wangii and P. eremitana. The imperfectly known Taiwanese P. uyematsui, mostly included in the other Taiwanese endemic P. morrisonicola, is maintained as a separate species similar to the Vietnamese P. dalatensis, and a hybrid between the two Taiwanese species is described as the nothospecies P. ×hayatana. The E Himalayan P. bhutanica is recognized as a subspecies of P. wallichiana.Akey to all members of P. subsect. Strobus, comprising nine Eurasian and six American species, and a revised classification of the Eurasian species in two series and three subseries, one series and two subseries here described as new, are provided.
Подробнее Год издания: 2004
Nuclear and cytoplasmic genetic diversity reveals long-term population decline in Abies semenovii, an endemic fir of central Asia
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The genus Abies is one of the largest conifer genera and many of the marginal species remain poorly characterized. Abies semenovii B. Fedtsch. is a rare mountain fir species from central Asia, and its species status is still disputed. We used both nuclear (allozymes and AFLP) and chloroplastic (cpS...SR) markers to show that A. semenovii deserves to be considered as a species and that its low genetic diversity justifies more a proactive conservation policy. First, A. semenovii was significantly differentiated from the Siberian fir Abies sibirica Ledeb. and we did not detect gene flow between the two species. Second, A. semenovii has a very low nuclear genetic diversity, suggesting a prolonged restricted effective population size. Abies semenovii had low cpSSR diversity too but the identification of seven closely related haplotypes suggests that these mutations accumulated recently during a phase of population expansion. This agrees well with the palynological record and is in contrast with the situation observed in another rare Eurasian fir endemic to Kamchatka, Abies gracilis Kom., which was devoid of variation in cpSSRs but that also had a more substantial nuclear marker diversity than A. semenovii, thereby suggesting a more recent but less severe population bottleneck.
Подробнее Год издания: 2012
Post-glacial history and introgression in Abies (Pinaceae) species of the Russian Far East inferred from both nuclear and cytoplasmic markers
Просмотров: 283 Rating Star
The main aim of the present study is to infer the post-glacial history of Abies species from north-east Asia and to test the hypotheses that coastal Abies populations suffered less from climatic fluctuations during Pleistocene glacial periods than their more continental counterparts, and that Sakha...lin was a major area of introgression.
Подробнее Год издания: 2011
Molecular Phylogenetic Analysis of the Genus Abies (Pinaceae) Based on the Nucleotide Sequence of Chloroplast DNA
Просмотров: 276 Rating Star
A phylogenetic study of firs (Abies Mill.) was conducted using nucleotide sequences of several chloroplast DNA regions with a total length of 5580 bp. The analysis included 37 taxa, which represented the main evolutionary lineages of the genus, and Keteleeria davidiana. According to phylogenetic re...construction, the Abies species were subdivided into six main groups, generally corresponding to their geographic distribu tion. The phylogenetic tree had three basal clades. All of these clades contained American species, and only one of them contained Eurasian species. The divergence time calibrations, based on paleobotanical data and the chloroplast DNA mutation rate estimates in Pinaceae, produced similar results. The age of diversification among the basal clades of the presentday Abies was estimated as the end of the Oligocene–beginning of Miocene. The age of the separation of Mediterranean firs from the Asian–North American branch corre sponds to the Miocene. The age of diversification within the young groups of Mediterranean, Asian, and “boreal” American firs (A. lasiocarpa, A. balsamea, A. fraseri) was estimated as the Pliocene—Pleistocene. Based on the phylogenetic reconstruction obtained, the most plausible biogeographic scenarios were sug gested. It is noted that the existing systematic classification of the genus Abies strongly contradicts with phy logenetic reconstruction and requires revision.
Подробнее Год издания: 2014
Genetic Differentiation of Spruce Populations in Northwest Russia According to the Results of Microsatellite Loci Analysis
Просмотров: 389 Rating Star
Analysis of the genetic diversity of the spruce populations in the northwest of the European part of Russia using microsatellite markers revealed two relatively isolated genetic clusters. One of them is com posed of trees that were identified as P. abies according to morphological traits. Another ...cluster unites spruces that were determined as P. obovata and P. fennica. The results of SSR analysis do not support the idea of the taxonomic independence of the hybridogeneous P. fennica species. The frequency of genotypes attributed to P. abies (according to the results of microsatellite markers) decreases significantly from south to north.
Подробнее Год издания: 2013
Pinus fenzeliana Hand.-Mazz. (Pinaceae) still misinterpreted?
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Despite the clarification of long-lasting problems with the interpretation of the name Pinus fenzeliana Hand.-Mazz. by Businsky 2004 and the selection of a neotype, at least two authors have recently connected this name with fundamentally different taxa following the old concept based on several co...nfusions caused by insufficiency and later through the absence of original material. Relevant misinterpretations are reviewed and a photo of the neotype specimen of P fenzeliana is given along with a photo of the most commonly confused taxon, P. wangii H. H. Hu & W. C. Cheng subsp. kwangtungensis (Chun ex Tsiang) Businsky. Diagnostic characters of P. fenzeliana (leaves ± drooping, mostly 12-19 cm long and less than 1 mm wide, cones erecto-patent, seeds mostly 10-15 mm long, with a rudimentary, lacerate, ineffective wing) and five other taxa (all of P. sect. Quinquefoliae) often confused with it are summarized.
Подробнее Год издания: 2010
Typification of specific and infraspecific names in Abies, Larix, Picea, and Pinus (Pinaceae)
Просмотров: 393 Rating Star
In connection with systematic studies of the genera Abies, Larix, Picea, and Pinus (Pinaceae) lectotypes are designated for Abies pinsapo var. baborensis, Larix × czekanowskii (= L. gmelinii × L. sibirica), Larix dahurica, L. griffithii, Picea abies var. arctica, P. maximowiczii, P. schrenkiana, Pi...nus brunoniana (≡ Tsuga brunoniana), P. canariensis, P. coronans, P. × neilreichiana (= P. nigra × P. sylvestris), P. smithiana (≡ Picea smithiana), and P. sylvestris vars. baliosperma, leucosperma, melanocarpa, mongolica, mongolica, and phaeosperma. Lectotypes and epitypes are designated for Pinus pumilio var. applanata and P. uncinata var. rotundata f. mughoides, as well as an epitype for P. mugo. Furthermore, various original material has been located for Abies sibirica, Pinus altamiranoi, P. ayachahuite, P. khasya, P. × litvinovii (P. sylvestris × tabulaeformis), P. pityusa, and P. pringlei, as well as Tsuga longibracteata (≡ Nothotsuga longibracteata).
Подробнее Год издания: 2006
Просмотров: 286 Rating Star
Анализ генетического разнообразия популяций ели на Северо-Западе Европейской части России с использованием микросателлитных маркеров выявил два относительно обособленных генетических кластера. Один из них составляют деревья, идентифицированные по морфологическим признакам как P.abies. Другой класте...р объединяет ели, определенные как P.obovata и P.fennica. Результаты SSR-анализа не поддерживают идею о таксономической самостоятельности гибридогенного вида P.fennica. Частота встречаемости генотипов, отнесенных по результатам микросателлитного маркирования к P.abies, достоверно убывает с юга на север.
Подробнее Год издания: 2015
К систематике и географическому распространению Ели финской (Picea fennica (Regel) Kom., Pinaceae)
Просмотров: 289 Rating Star
В статье приведены история изучения, отличительные морфологические признаки вегетативных и репродуктивных органов и географическое распространение Picea fennica (Regel) Kom. и близких к ней видов P. abies (L.) H. Karst. и P. obovata Ledeb. Высказано мнение о гибридогенной природе P. fennica — молод...ого, не до конца сложившегося вида. Показано, что на протяжении своего обширного ареала ель финская встречается в двух основных формах: близкой к P. abies и близкой к P. obovata. Отмечена также промежуточная форма P. fennica, которая по морфологии шишек проявляет промежуточные признаки, но по вегетативным признакам более близка к P. obovata. Выявлены интересные закономерности в географическом распространении этой промежуточной формы.
Подробнее Год издания: 2014
Taxonomic Revision and Conspectus of Pinus in Vietnam
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Vietnam shows one of the greatest conifer diversity in Eurasia, and Pinus is the genus with the highest species richness (8 species). There is a great taxonomic confusion or there are only provisional identifications of Pinus species in the relevant literature. In this study Vietnamese populations ...of pines with controversial identities have been taxonomically reassessed. All taxa are summarised and geographical distribution on the basis of the author’s field knowledge of Asian pine species is given.
Подробнее Год издания: 2013
Southern montane populations did not contribute to the recolonization of West Siberian Plain by Siberian larch (Larix sibirica): a range-wide analysis of cytoplasmic markers
Просмотров: 263 Rating Star
While many species were confined to southern latitudes during the last glaciations, there has lately been mounting evidence that some of the most cold-tolerant species were actually able to survive close to the ice sheets. The contribution of these higher latitude outposts to the main recolonizatio...n thrust remains, however, untested. In the present study, we use the first range-wide survey of genetic diversity at cytoplasmic markers in Siberian larch (Larix sibirica; four mitochondrial (mt) DNA loci and five chloroplast (cp) DNA SSR loci) to (i) assess the relative contributions of southern and central areas to the current L. sibirica distribution range; and (ii) date the last major population expansion in both L. sibirica and adjacent Larix species. The geographic distribution of cpDNA variation was uninformative, but that of mitotypes clearly indicates that the southernmost populations, located in Mongolia and the Tien-Shan and Sayan Mountain ranges, had a very limited contribution to the current populations of the central and northern parts of the range. It also suggests that the contribution of the high latitude cryptic refugia was geographically limited and that most of the current West Siberian Plain larch populations likely originated in the foothills of the Sayan Mountains. Interestingly, the main population expansion detected through Approximate Bayesian Computation (ABC) in all four larch species investigated here pre-dates the LGM, with a mode in a range of 220 000–1 340 000 years BP. Hence, L. sibirica, like other major conifer species of the boreal forest, was strongly affected by climatic events pre-dating the Last Glacial Maximum.
Подробнее Год издания: 2013
Просмотров: 301 Rating Star
A new species of Pinus subgen. Strobus, discovered for the fi rst time in 2006 on the Vietnamese border of Laos at 17°40´N, is described as Pinus anemophila on the basis of the author’s new collection. According to the species’ morphology, es pecially the cones and large seeds with a relatively sho...rt wing, it belongs to P. sect. Quinquefoliae subsect. Strobus subser. Wangianae. It is a local relict limited to the eastern margin of Phou Ak sandstone plateau in Khammouan Province (central Laos) between 800 and 1100 m.
Подробнее Год издания: 2010
Morphological, anatomical and genetic differentiation of Cornus mas, Cornus officinalis and their interspecific hybrid
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Cornus mas L., C. officinalis Sieb. et Zucc. and their putative interspecific hybrid specimens were examined in order to describe their morphological, anatomical and genetic differentiation. Petiole length, number of leaf veins, pedicel and bract length, stone size, thickness of pericarp layers, th...e size and number of locules and the number of cavities were measured. Pedicels and bracts were shown to be significantly longer for C. mas (7.22 and 6.95 mm) and for the putative hybrid (9.11 and 6.61 mm) than for C. officinalis (6.86 and 5.81 mm, respectively). Average values of stone width and thickness, exocarp and mesocarp thickness, the number of cavities in the endocarp obtained for the putative hybrid differed significantly in comparison to C. mas and were similar to C. officinalis. Genotypes of the examined species were evaluated for genetic relationships using random amplified polymorphic DNA (RAPD) markers. Initial screening of the bulks of C. mas and C. officinalis compared with their putative hybrid using 72 decamer random primers resulted in the identification of 24 primers differentiating both species and their putative hybrid and showing reliable polymorphisms. Among a total of 485 amplified fragments, 89.7% were polymorphic, 18.8% were specific to C. mas individuals, and 18.6% were specific to the individuals of C. officinalis. In obtained profiles of the examined hybrid individual specific products absent in the genotypes of both parents were observed. The phylogenetic tree revealed two separate clusters including C. mas and C. officinalis accessions, respectively. The biggest genetic distance was observed for hybrid specimens, although the hybrid belonged to the C. mas cluster.
Подробнее Год издания: 2012
Problems in the Field of Systematics and Investigation of Conifers in Russia
Просмотров: 222 Rating Star
The largest and most important family in Russian conifers is Pinaceae (27-29 species). The most important problems in the field of systemitics concern some critical taxa. In the result of author’s research, the new signs of vegetative and reproductive organs have been checked out and elaborated. It... leads to the clarifying of new taxonomic status and geographical distribution of certain critical taxa. A set of species are threatened and need special measures for their conservation. There are 13 species and one variety which are included into the Red Data Book of Russian Federation.
Подробнее Год издания: 2013