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161.
E. W. JONES 《The New phytologist》1935,34(2):155-155
162.
M. A. HANNAN‐JONES A. J. LOWE K. D. SCOTT G. C. GRAHAM J. P. PLAYFORD M. P. ZALUCKI 《Molecular ecology resources》2005,5(4):770-773
Nine microsatellite loci were developed, and are transferable, across the Madagascan succulents Bryophyllum daigremontianum, Bryophyllum delagoense (mother‐of‐millions) and their horticultural hybrid (Houghton's), from enriched libraries of the later two species. For B. delagoense, a tetraploid, three to 13 alleles per locus were found for native Madagascan (HO = 0.4–1.0), and one to nine in invasive Australian (HO = 0.0–1.0) samples. In addition for 91 Australian samples, only five multilocus genotypes were found (95% of individuals were of two genotypes), suggesting extensive clonality in its introduced range. These loci will be used to examine genetic diversity, hybrid origin and mating system in natural and introduced populations. 相似文献
163.
DAVID A. SIMPSON fls A. MUTHAMA MUASYA KONGKANDA CHAYAMARIT JOHN A. N. PARNELL fls SOMRAN SUDDEE BART D. E. WILDE MICHAEL B. JONES JEREMY J. BRUHL RACHUN POOMA 《Botanical journal of the Linnean Society. Linnean Society of London》2005,149(3):357-364
Khaosokia caricoides , D.A. Simpson, Chayam. & J. Parn., a newly discovered genus and species of Cyperaceae is described and illustrated. The genus is characterized by a narrowly paniculate dioecious inflorescence with 2–4 nodes, each of the nodes having a leaf-like inflorescence bract that exceeds the inflorescence. Spikelets in both sexes are linear-cylindric and each flower has seven perianth bristles. The nutlet was immature in the specimens examined. The photosynthetic pathway is C3 . Khaosokia is endemic to limestone cliffs in peninsular Thailand; its conservation status is assessed as Vulnerable (VU B1a + 2a). It has affinities to tribes Cariceae, Dulichieae and some members of Scirpeae, but the exact nature of these relationships has yet to be determined. A revised key to the genera of Cyperaceae in Thailand is presented. © 2005 The Linnean Society of London, Botanical Journal of the Linnean Society , 2005, 149 , 357–364. 相似文献
164.
MARK BOLTON ANDREA L. SMITH ELENA GÓMEZ‐DÍAZ VICKI L. FRIESEN RENATA MEDEIROS JOËL BRIED JOSE L. ROSCALES ROBERT W. FURNESS 《Ibis》2008,150(4):717-727
The existence of two seasonally distinct breeding populations of Oceanodroma storm‐petrels in the Azores islands was first documented in 1996. The discovery of morphological differences between the populations led to the suggestion that they may represent cryptic sibling species. Recent mtDNA and microsatellite analysis from storm‐petrel populations has considerably advanced our understanding of their taxonomic relationships. Here we present new information on the timing of breeding and moult of the two Azores populations, the extent of exchange of individuals between seasons, and diet from feather isotopes. We conclude that the hot‐season Azores population should be considered a new species for which we propose the name Oceanodroma monteiroi, Monteiro's Storm‐petrel. The species is both genetically distinct and genetically isolated from the sympatric cool‐season population of Madeiran Storm‐petrel Oceanodroma castro, and from all other populations of Oceanodroma castro in the Atlantic and Pacific Oceans examined to date. Differences in the vocalizations permit species recognition, and the extent of primary feather wear and stage of moult aids separation of the two species in the Azores, which is especially valuable during August when both attend the breeding colonies in large numbers. Feather carbon and nitrogen isotopes reveal that the diet of Monteiro's Storm‐petrel differs from that of the sympatric Madeiran Storm‐petrel during both breeding and non‐breeding seasons, and unlike the Madeiran Storm‐petrel, Monteiro's Storm‐petrel appears to maintain the same foraging environment during the summer and winter months, though it shows a dietary shift to higher trophic levels during the non‐breeding season. Monteiro's Storm‐petrel is thought to be confined to the Azores archipelago, where it is currently known to nest on just two small neighbouring islets. The total population size was estimated at 250–300 pairs in 1999. 相似文献
165.
KATHERINE M. PEASE ADAM H. FREEDMAN JOHN P. POLLINGER JOHN E. MCCORMACK† WOLFGANG BUERMANN† JEFF RODZEN‡ JIM BANKS‡ ERIN MEREDITH‡ VERNON C. BLEICH§ ROBERT J. SCHAEFER¶ KEN JONES ROBERT K. WAYNE† 《Molecular ecology》2009,18(9):1848-1862
Landscape genetics is an emerging discipline that utilizes environmental and historical data to understand geographic patterns of genetic diversity. Niche modelling has added a new dimension to such efforts by allowing species–environmental associations to be projected into the past so that hypotheses about historical vicariance can be generated and tested independently with genetic data. However, previous approaches have primarily utilized DNA sequence data to test inferences about historical isolation and may have missed very recent episodes of environmentally mediated divergence. We type 15 microsatellite loci in California mule deer and identify five genetic groupings through a Structure analysis that are also well predicted by environmental data. We project the niches of these five deer ecotypes to the last glacial maximum (LGM) and show they overlap to a much greater extent than today, suggesting that vicariance associated with the LGM cannot explain the present-day genetic patterns. Further, we analyse mitochondrial DNA (mtDNA) sequence trees to search for evidence of historical vicariance and find only two well-supported clades. A coalescence-based analysis of mtDNA data shows that the genetic divergence of the mule deer genetic clusters in California is recent and appears to be mediated by ecological factors. The importance of environmental factors in explaining the genetic diversity of California mule deer is unexpected given that they are highly mobile species and have a broad habitat distribution. Geographic differences in the timing of reproduction and peak vegetation as well as habitat choice reflecting natal origin may explain the persistence of genetic subdivision. 相似文献
166.
167.
PHILLIP D. JONES SCOTT L. EDWARDS STEPHEN DEMARAIS 《The Journal of wildlife management》2009,73(4):488-496
ABSTRACT Stand establishment techniques involving multiple herbicide applications are commonly used on industrial pine (Pinus spp.) plantations, raising concern over potential effects on white-tailed deer (Odocoileus virginianus) forage production. We tested effects of stand establishment intensity on deer forage in 1–5-year-old loblolly pine (Pinus taeda) plantations (n = 4) in the East Gulf Coastal Plain of Mississippi using forage biomass and 4 measures of nutritional carrying capacity that reflected crude protein or digestible energy requirements for body maintenance and lactation. We also assessed whether forage biomass combined with a deer use rating effectively indexed nutritional carrying capacity. Treatments were combinations of mechanical site preparation, chemical site preparation (CSP), and herbaceous weed control (HWC). Total forage biomass and forage biomass of grasses and forbs were reduced by broadcast HWC. Forage biomass of vines was reduced both by CSP and by multiple broadcast HWC applications. Maintenance-level carrying capacity estimates were reduced by broadcast HWC; lactation-level estimates were higher in moderate-intensity treatments. We believe the inherently low fertility of this region makes high-quality forage production a more important management priority than increasing forage quantity. Chemical or chemical and mechanical site preparation combined with banded HWC provided the best option for providing both forage quality and quantity in open-canopied, intensively managed pine plantations. Biomass-based indices may be suitable for indexing protein-based maintenance-level carrying capacity in this region, but our results indicated they were not useful for indexing other carrying capacity estimates. 相似文献
168.
MYRIAN RYBAK GERALD V. MINSAVAGE ROBERT E. STALL JEFFREY B. JONES 《Molecular Plant Pathology》2009,10(2):249-262
We provide the first conclusive evidence that Xanthomonas axonopodis pv. citri Asiatic strain (Xac-A) and, in particular, Xac-Aw , a unique citrus canker A strain isolated from Key lime in Wellington, Florida, induces a hypersensitive reaction (HR) in grapefruit leaves. Using the heterologous tomato pathogen X. perforans , as a recipient of the Xac-Aw genomic library, we identified a 1599-bp open reading frame responsible for HR in grapefruit, but not Key lime, and designated it avrGf 1. Xac-Aw Δ avrGf 1 produced typical, although visibly reduced, citrus canker symptoms (i.e. raised pustules) in grapefruit and typical canker symptoms in Key lime. We also determined that the X. perforans transconjugant carrying an Xac-Aw hrpG elicited HR in grapefruit and Key lime leaves, and that xopA in X. perforans was partly responsible for HR. Xac-A transconjugants carrying the X. perforans xopA were reduced in ability to grow in grapefruit leaves relative to wild-type Xac-A. The X. perforans xopA appears to be a host-limiting factor. An avrBs3 homologue, which contained 18.5 repeats and induced HR in tomato, was designated avrTaw . This gene, when expressed in a pustule-minus Xac-Aw , did not complement pustule formation; however, pthAw , a functional pthA homologue, complemented the mutant strain to produce typical pustules in Key lime, but markedly reduced pustules in grapefruit. Both avrBs3 homologues, when expressed in a typical Xac-A strain, resulted in typical citrus canker pustules in grapefruit, indicating that neither homologue suppressed pustule size in grapefruit. Xac-Aw contains other unidentified factors that suppress development in grapefruit. 相似文献
169.
STEPHEN J. THACKERAY TIMOTHY H. SPARKS MORTEN FREDERIKSEN SARAH BURTHE PHILIP J. BACON JAMES R. BELL MARC S. BOTHAM TOM M. BRERETON PAUL W. BRIGHT LAURENCE CARVALHO TIM CLUTTON‐BROCK ALISTAIR DAWSON MARTIN EDWARDS J. MALCOLM ELLIOTT RICHARD HARRINGTON DAVID JOHNS IAN D. JONES JAMES T. JONES DAVID I. LEECH DAVID B. ROY W. ANDY SCOTT MATT SMITH RICHARD J. SMITHERS IAN J. WINFIELD SARAH WANLESS 《Global Change Biology》2010,16(12):3304-3313
Recent changes in the seasonal timing (phenology) of familiar biological events have been one of the most conspicuous signs of climate change. However, the lack of a standardized approach to analysing change has hampered assessment of consistency in such changes among different taxa and trophic levels and across freshwater, terrestrial and marine environments. We present a standardized assessment of 25 532 rates of phenological change for 726 UK terrestrial, freshwater and marine taxa. The majority of spring and summer events have advanced, and more rapidly than previously documented. Such consistency is indicative of shared large scale drivers. Furthermore, average rates of change have accelerated in a way that is consistent with observed warming trends. Less coherent patterns in some groups of organisms point to the agency of more local scale processes and multiple drivers. For the first time we show a broad scale signal of differential phenological change among trophic levels; across environments advances in timing were slowest for secondary consumers, thus heightening the potential risk of temporal mismatch in key trophic interactions. If current patterns and rates of phenological change are indicative of future trends, future climate warming may exacerbate trophic mismatching, further disrupting the functioning, persistence and resilience of many ecosystems and having a major impact on ecosystem services. 相似文献
170.
ADORA THABAH STEPHEN J. ROSSITER TIGGA KINGSTON SHUYI ZHANG STUART PARSONS KHIN MYA MYA AKBAR ZUBAID GARETH JONES 《Biological journal of the Linnean Society. Linnean Society of London》2006,88(1):119-130
The intermediate leaf-nosed bat ( Hipposideros larvatus ) is a medium-sized bat distributed throughout the Indo-Malay region. In north-east India, bats identified as H. larvatus captured at a single cave emitted echolocation calls with a bimodal distribution of peak frequencies, around either 85 kHz or 98 kHz. Individuals echolocating at 85 kHz had larger ears and longer forearms than those echolocating at 98 kHz, although no differences were detected in either wing morphology or diet, suggesting limited resource partitioning. A comparison of mitochondrial control region haplotypes of the two phonic types with individuals sampled from across the Indo-Malay range supports the hypothesis that, in India, two cryptic species are present. The Indian 98-kHz phonic bats formed a monophyletic clade with bats from all other regional populations sampled, to the exclusion of the Indian 85-kHz bats. In India, the two forms showed 12–13% sequence divergence and we propose that the name Hipposideros khasiana for bats of the 85-kHz phonic type. Bats of the 98-kHz phonic type formed a monophyletic group with bats from Myanmar, and corresponded to Hipposideros grandis , which is suggested to be a species distinct from Hipposideros larvatus . Differences in echolocation call frequency among populations did not reflect phylogenetic relationships, indicating that call frequency is a poor indicator of evolutionary history. Instead, divergence in call frequency probably occurs in allopatry, possibly augmented by character displacement on secondary contact to facilitate intraspecific communication. © 2006 The Linnean Society of London, Biological Journal of the Linnean Society , 2006, 88 , 119–130. 相似文献