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1.
Jan Timbrook 《Economic botany》1990,44(2):236-253
At least 150 plant species were used for food, medicine, material culture, and religious practices by the Chumash Indians of southern California. A great deal of traditional Chumash plant knowledge survived into the present century, despite massive deculturation. The most significant source of information on Chumash ethnobotany is the extensive, unpublished field notes of John P. Harrington, based on interviews conducted from 1912 into the 1950s. Several hundred voucher specimens collected by some of Harrington’s consultants have also been preserved, along with the original notes, at the Smithsonian Institution. Data are presented here on knowledge and uses of plants in this important California Indian culture, as reconstructed from the Harrington material. Changes in plant knowledge resulting from Euro-American contact are also discussed. 相似文献
2.
Lesley T. Lancaster Kathleen M. Kay 《Evolution; international journal of organic evolution》2013,67(4):1041-1054
The California Floristic Province exhibits one of the richest floras on the planet, with more than 5500 native plant species, approximately 40% of which are endemic. Despite its impressive diversity and the attention it has garnered from ecologists and evolutionary biologists, historical causes of species richness and endemism in California remain poorly understood. Using a phylogenetic analysis of 16 angiosperm clades, each containing California natives in addition to species found only outside California, we show that CA's current biodiversity primarily results from low extinction rates, as opposed to elevated speciation or immigration rates. Speciation rates in California were lowest among Arcto‐Tertiary lineages (i.e., those colonizing California from the north, during the Tertiary), but extinction rates were universally low across California native plants of all historical, geographic origins. In contrast to long‐accepted ideas, we find that California diversification rates were generally unaffected by the onset of the Mediterranean climate. However, the Mediterranean climate coincided with immigration of many desert species, validating one previous hypothesis regarding origins of CA's plant diversity. This study implicates topographic complexity and climatic buffering as key, long‐standing features of CA's landscape favoring plant species persistence and diversification, and highlights California as an important refuge under changing climates. 相似文献
3.
Evolution is receiving increased attention as a potentially important factor in invasions. For example, hybridization may
have stimulated the evolution of invasiveness in several well-known plant pests. However, the mechanism for success of such
hybrid-derived lineages remains unknown in the majority of the cases studied. Here we ask whether increased reproductive success
(in terms of maternal fitness) has evolved in an invasive lineage with confirmed hybrid ancestry. We compare the relative
fitness of the non-native, hybrid-derived California wild radish (Raphanus sativus) to that of its two progenitor species in field experiments at different sites and in different years. We found that California
wild radish has high survivorship and produces more fruits per plant and more seeds per plant than either of its progenitors
in several environments. Furthermore, populations of California wild radish display a strong genotype-by-environment interaction,
indicating that maintenance of genetic and phenotypic diversity between populations may be responsible for the weed’s ability
to invade a wide breadth of California habitats. Our results suggest that hybridization may contribute the evolution of enhanced
invasiveness and, also, that by limiting the introduction and subsequent hybridization of congeners, we may be able to prevent
the evolution of new invasive lineages. 相似文献
4.
Islands, Exotic Herbivores, and Invasive Plants: Their Roles in Coastal California Restoration 总被引:2,自引:0,他引:2
Abstract The Pacific islands off southern California, U.S.A. and Baja California, Mexico hold potential for the conservation and restoration of California Mediterranean coastal ecosystems. However, the presence of exotic herbivores and invasive plants pose threats to these systems. Here, we use introduced herbivore removal as a large‐scale experimental manipulation to examine the importance of top‐down and bottom‐up processes to a large‐scale restoration effort. Using a paired approach on the Todos Santos Islands, Mexico we removed herbivores from one island, while they temporarily remained on an adjacent and similar island. We augmented this experiment with smaller scale herbivore exclosures on the control island. At both scales we failed to detect an herbivore effect on the plant community; rather plant community dynamics appeared to be dominated by El Niño related precipitation and exotic annuals. A parallel experiment on the San Benito Islands, Mexico revealed a different dynamic: Top‐down effects on the plant community by exotic herbivores were evident. Differences in the response from the plant communities to both exotic herbivore presence and removal between these two island groups, along with Santa Barbara Island, U.S.A., where restoration has been on‐going, raise important questions in ecosystem restoration. The history of anthropogenic disturbance, exotic plant abundance, and aridity play roles in postherbivore removal recovery. Although island conservation practitioners have honed the ability to remove exotic mammals from islands, development of invasive plant removal techniques is needed to fully capitalize on the conservation potential of California island ecosystems. 相似文献
5.
Contemporary patterns in a historical context: phylogeographic history of the pipevine swallowtail,Battus philenor (Papilionidae) 总被引:1,自引:0,他引:1
Abstract We examined mitochondrial DNA (mtDNA) variation in pipevine swallowtail butterflies ( Battus philenor ) from throughout its extant range to provide a historical, phylogeographical context for ecological studies of the disjunct population in California. We evaluate current hypotheses regarding host plant use, behavior, and mimetic relationships of B. philenor populations and generate alternative hypotheses. Compared to populations throughout the rest of the species' range, California populations are ecologically distinct in that they lack mimics, lay significantly larger clutches of eggs, and exclusively use a unique, endemic larval host plant. Analysis of molecular variance, tests of population differentiation, and nested clade analysis of mtDNA variation indicate that, despite low levels of population genetic structure across the species' range, there is evidence of recent range expansion from presumed Pleistocene refuge(s) in southeastern North America. Colonization of California appears to have been a recent event. This phylogeographic investigation also suggests that the evolution of life-history adaptations to a novel larval host has occurred rapidly in California and the lack of mimics in California may be attributable to the recency of colonization. 相似文献
6.
Nicolas Rasmussen 《Journal of the history of biology》1999,32(2):245-261
The physiology of plant hormones was one of the most dynamic fields in experimental biology in the 1930s, and an important
part of T. H. Morgan's influential life science division at the California Institute of Technology. I describe one episode
of plant physiology research at the institution in which faculty member James Bonner discovered that the B vitamin thiamin
is a plant growth regulator, and then worked in close collaboration with the Merck pharmaceutical firm to develop it as a
growth-boosting agrichemical. This episode allows one to draw continuities between certain fields of life science in the United
States circa 1940 and the biotechnology industry today, and also foregrounds a number of similarities between plant physiology
of the late 1930s and the molecular biology of the period.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
7.
Luis Inostroza Alejandro del Pozo Ivan Matus Dalma Castillo Patrick Hayes Stephen Machado Ann Corey 《Molecular breeding : new strategies in plant improvement》2009,23(3):365-376
Grain yield and plant height of 80 recombinant chromosome substitution lines (RCSLs) of barley were measured in six environments
with contrasting available moisture profiles. Two environments were in OR, USA (Moro and Pendleton) during one growing season
(2004), and four in Chile (Cauquenes and Santa Rosa) during two growing seasons (2004/2005 and 2007/2008). From the yield
data obtained in the different environments, yield adaptability (Finlay–Wilkinson slope) and stability (deviations from regression)
were calculated. Two commercial cultivars (Harrington and Baronesse) were used as checks in all environments. Marker-quantitative
trait associations were identified using 47 simple sequence repeats (SSRs) and the general linear model (GLM) implemented
in TASSEL. The mean plant height and grain yield of the 80 RCSLs differed greatly across environments, reflecting differences
in water availability. In all environments, there were significant differences (P < 0.05) in grain yield among RCSLs. There was also abundant variation in yield adaptability, indicating a differential response
of the RCSLs to environmental conditions across environments. Using principal component analysis, it was possible to identify
genotypes with better agronomic performance than the recurrent parent cv. Harrington. The association analysis revealed 21
chromosomal regions that were highly correlated with differences in grain yield, plant height and/or yield adaptability (Finlay–Wilkinson
slope). In approximately one-fourth of the cases, the H. spontaneum donor contributed favorable alleles. The associations were referenced to the quantitative trait loci (QTL) for the same traits
reported in the literature. 相似文献
8.
Aphytis melinus DeBach (Hymenoptera: Aphelinidae) is a biological control agent of diaspidid scale insects. The parasitoid has a narrow host range but its hosts are polyphagous. We determined the source of volatile cues the wasp uses to locate its few host species when those hosts occur on more than one host plant species. We addressed four questions in regard to the use of volatile cues in host location of California red scale, Aonidiella aurantii (Maskell) (Homoptera: Diaspididae): (1) Does A. melinus use volatile cues to assist in host location? (2) Are these cues innately recognized or learned? (3) Are cues produced by female California red scale, or from other sources? (4) Are the cues specific to the host or host plant? These questions were tested through the use of a Y-tube olfactometer. Female A. melinus used volatile cues to orient toward both infested and uninfested host plant material. Wasps learned these cues by associating odors from the host plant with host presence. They had no innate preferences for scale insect or host plant volatile stimuli. Contrary to previous studies, we found no evidence of orientation toward the female-produced sex pheromone of California red scale, nor to volatile cues from the attacked host stage. Wasps given experience with scale insects growing on lemon fruit subsequently oriented toward lemon and orange fruit and leaves. The scale species with which the wasp was given experience did not affect this preference. Wasps given experience with California red scale growing on squash did not orient toward infested lemon fruit. The host ranges of the parasitoid and its hosts are used to explain the adaptive value for the evolution of learned rather than fixed responses to cues used in foraging behavior. 相似文献
9.
Invasive species cover,soil type,and grazing interact to predict long‐term grassland restoration success
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Grasslands are undergoing tremendous degradation as a result of climate change, land use, and invasion by non‐native plants. However, understanding of the factors responsible for driving reestablishment of grassland plant communities is largely derived from short‐term studies. In order to develop an understanding of the factors responsible for longer term restoration outcomes in California annual grasslands, we surveyed 12 fields in Davis, CA, U.S.A., in 2015 that were seeded with native species mixtures starting in 2004. Using field surveys, we investigated how invasive plant richness and cover, native plant richness and cover, aboveground biomass, grazing, soil type, and restoration species identity might provide utility for explaining patterns of restoration success. We found a negative relationship between invasive cover and restoration cover, which was attributed to the slow establishment of seeded species and subsequent dominance by weeds. The relationship between invasive cover and restoration cover was modified by grazing, likely due to a change in the dominance of exotic forbs, which have a more similar growing season to restoration species, and therefore compete more strongly for late season moisture. Finally, we found that soil type was responsible for differences in the identity and abundance of invasive plants, subsequently affecting restoration cover. This work highlights the value of focusing resources on reducing invasive species cover, limiting grazing to periods of adequate moisture, and considering soil type for successful long‐term restoration in California annual grasslands. Moreover, observations of long‐term restoration outcomes can provide insight into the way mechanisms driving restoration outcomes might differ through time. 相似文献
10.
Lee Sung J. Penner Greg A. 《Molecular breeding : new strategies in plant improvement》1997,3(6):457-462
Application of marker-assisted selection with RFLP based markers has been constrained by high cost and time requirements in situations involving a large number of plants. RFLP markers mapped on a Harrington/TR306 population have been identified elsewhere as linked to quantitative trait loci (QTL) governing malting quality. The probes ABG610, ABC622, as well as probes for the Nar1, Amy1 and Nar7 were sequenced and locus specific primers developed. These locus specific primers were applied to genomic DNA from both Harrington and TR306. Sequence analysis of the resultant monomorphic fragments revealed sequence divergence for the Xabg610, Xabc622, Amy1 and Nar1 loci, but not for the Nar7 locus. Application of a set of Hor2 primers to genomic DNA from the barley lines Harrington and TR306 led to the direct amplification of codominant alleles. Allele-specific primers were designed based on the sequence divergence identified among the Xabg610, Xabc622 and Nar1 alleles. Amplification conditions were optimized for each of these alleles such that only the favourable allele from Harrington was amplified. The usefulness of these primers for selecting Harrington alleles was demonstrated by their failure to amplify the corresponding alleles from the lines, Sterling, Stella and WM872. The Amy1 allele-specific amplicon was only capable of differentiating this locus between Harrington and TR306. The conversion of these markers into PCR amplifiable, allele-specific amplicons would greatly facilitate their application to barley breeding programs. 相似文献
11.
Knowledge of population genetic structure of tanoak (Lithocarpus densiflorus) is of interest to pathologists seeking natural variation in resistance to sudden oak death disease, to resource managers who need indications of conservation priorities in this species now threatened by the introduced pathogen (Phytophthora ramorum), and to biologists with interests in demographic processes that have shaped plant populations. We investigated population genetic structure using nuclear and chloroplast DNA (cpDNA) and inferred the effects of past population demographic processes and contemporary gene flow. Our cpDNA results revealed a strong pattern of differentiation of four regional groups (coastal California, southern Oregon, Klamath mountains, and Sierra Nevada). The chloroplast haplotype phylogeny suggests relatively deep divergence of Sierra Nevada and Klamath populations from those of coastal California and southern Oregon. A widespread coastal California haplotype may have resulted from multiple refugial sites during the Last Glacial Maximum or from rapid recolonization from few refugia. Analysis of nuclear microsatellites suggests two major groups: (1) central coastal California and (2) Sierra Nevada/Klamath/southern Oregon and an area of admixture in north coastal California. The low level of nuclear differentiation is likely to be due to pollen gene flow among populations during postglacial range expansion. 相似文献
12.
Spread of exotic plants in the landscape: the role of time,growth habit,and history of invasiveness 总被引:1,自引:0,他引:1
Robert G. Ahern Douglas A. Landis Anton A. Reznicek Douglas W. Schemske 《Biological invasions》2010,12(9):3157-3169
We investigated the relative contribution of minimum residence time, growth habit, and history of invasiveness to the spread
of exotic plants in Michigan and California. Our data include minimum residence time as estimated by earliest herbarium collection
records, growth habit, and history of invasiveness for over 2000 records from two herbaria (MI = 943, CA = 1131). Our data
support the hypothesis that minimum residence time is highly associated with landscape spread, explaining 39–44% of variation
in the number of counties invaded. In contrast, growth habit and history of invasiveness explained a small fraction of variation
in spread in California but not Michigan. Over the past 30 years exotic plant species frequently became established in Michigan
and California (≥50 species per decade), suggesting that many more species will become invasive over time. There is an urgent
need to develop effective policies for exotic plant management. In both states we found significant positive correlations
between minimum residence time and species occurrence on state invasive plant lists. Further, we found historical information
on the pest status of a plant species introduced into a similar environment to be relevant in determining landscape spread
of exotic plants. We conclude that efforts to predict exotic species spread based on biological characteristics may have limited
success, and instead endorse pest risk analysis for proposed new imports coupled with rapid detection and early response for
unintended and unwanted introductions. 相似文献
13.
Clare E. Aslan 《Biological invasions》2011,13(12):2829-2845
I examined the role of bird dispersal in invasiveness of three non-native plant species in California, USA: Triadica sebifera, Ligustrum lucidum, and Olea europaea. I selected these species because their invasiveness in California is uncertain, but a survey of ornithologists highlighted
them as likely bird-dispersed. I quantified bird frugivory of these plants, compared them with a native species (Heteromeles arbutifolia), and explored the management implications of dispersal mutualisms for these and other incipient invasive plants. Fruit removal
by birds was sufficient to permit spread for all study species. Seed dispersers (rather than seed predators) and pulse feeders
(flocking species with potential for long distance dispersal) performed most fruit removal for the non-native species, a pattern
indicative of an effective dispersal regime. The number of fruiting trees per stand was a significant predictor of bird visitation.
Founding population size may thus be important in management of invasive, bird-dispersed plants. Disperser-defined niches
were relatively narrow because a few disperser species performed the majority of fruit removal from study trees, but each
fruit species was consumed by a variety of potential dispersers. This results in strong pairwise niche overlap between some
plant species. Ordinated by bird use, study site-species combinations clustered more by geographic location than by plant
species, emphasizing the opportunistic nature of bird foraging. None of the non-native focal plant species appears dispersal
limited, and all have formed novel mutualisms in California. It is possible that these plants are now in lag phases preceding
bird-mediated invasion. Consideration of bird dispersal when evaluating invasiveness is therefore an imperative. 相似文献
14.
M. Kat Anderson 《Economic botany》1996,50(4):409-422
Deergrass (Muhlenbergia rigens, Poaceae), a once abundant and widespread native perennial bunchgrass in California, was utilized extensively by at least twenty tribes for its flower stalks, incorporated into many types of coiled baskets. The craft of coiled basketry required the annual harvesting of thousands of culms by each village and the frequent setting of small-scale fires in many plant community types to eliminate detritus, recycle nutrients, increase culm production and prohibit shrub or tree encroachment. Detailed examination of Native American past fire management practices will provide insights into the cultural processes that shaped various ecosystem states, and unravel the ecological principles embedded in ancient land management systems. There are at least 300 contemporary Native American weavers and the successful revival of basketry in California is inextricably tied to access to and availability of plant resources on public lands. 相似文献
15.
Objective To compare the utilisation of hospital beds in the NHS in England, Kaiser Permanente in California, and the Medicare programme in the United States and California.Design Analysis of routinely available data from 2000 and 2001 on inpatient admissions, lengths of stay, and bed days in populations aged over 65 for 11 leading causes of use of acute beds.Setting Comparison of NHS data with data from Kaiser Permanente in California and the Medicare programme in California and the United States; interviews with Kaiser Permanente staff and visits to Kaiser facilities.Results Bed day use in the NHS for the 11 leading causes is three and a half times that of Kaiser''s standardised rate, almost twice that of the Medicare California''s standardised rate, and more than 50% higher than the standardised rate in Medicare in the United States. Kaiser achieves these results through a combination of low admission rates and relatively short stays. The lower use of bed days in Medicare in California compared with Medicare in the United States suggests there is a “California effect” as well as a “Kaiser effect” in hospital utilisation.Conclusion The NHS can learn from Kaiser''s integrated approach, the focus on chronic diseases and their effective management, the emphasis placed on self care, the role of intermediate care, and the leadership provided by doctors in developing and supporting this model of care. 相似文献
16.
We investigated one causal explanation for geographic variation in clutch size and aggregative feeding of the pipevine swallowtail, Battus philenor. Populations in California lay larger clutches than those in Texas, and larger feeding aggregations grow at an accelerated rate on the California host plant. Using reciprocal transplant experiments with larvae from California and Texas populations, we found that the benefit of increased growth rate associated with feeding in larger groups occurred only on the California host plant and was observed for larvae from both populations. These results are consistent with the hypothesis that larger clutch size and aggregative feeding are adaptations to characteristics of the California host plant. Future studies on the evolution of clutch size and aggregative feeding of herbivorous insects should consider how these life-history traits affect host plant suitability. 相似文献
17.
Edith A. Read 《Restoration Ecology》1994,2(2):80-86
Community classification has emerged from ecology textbooks into the arena of environmental impact evaluation and mitigation. This development is especially apparent in southern California, where the fate of a community called coastal sage scrub is being decided. Regional plans for development, mitigation, preservation, and restoration are being formulated that will permanently affect the natural landscape. This paper demonstrates the potential for the name of a plant community to affect tradeoffs in planning processes that are intended to offset removal of habitat by development. The discussion focuses on two types of classification systems. One system is hierarchical, with established nomenclatorial rules that allow natural variation to refine the community definitions. Names of plant associations directly reflect the dominant species in the association, as in Artemisia californica—Eriogonum fasciculatum (California sagebrush—California buckwheat). The second system is nonhierarchical, in which observations of natural landscapes are fit into established definitions of community types, such as Diegan coastal sage scrub. Advantages and disadvantages of both types of systems are discussed and illustrated by two examples of problems in classifying coastal sage scrub. The discussion concludes with the point that the name of a community has the potential to significantly affect the extent to which equal tradeoffs between community types are actually achieved in mitigation and restoration efforts. 相似文献
18.
The evolutionary processes that take place in invasive plant populations are not well documented or understood. Interspecific hybridization between cultivated radish (Raphanus sativus) and R. raphanistrum is known to be responsible for the origin of the invasive California wild radish, but little is known about the nature of the hybridization events that produced the hybrid-derived lineage. We analyzed the trnL-rpl32 intergenic region of chloroplast DNA (cpDNA) obtained from 37 cultivated radish individuals from four different cultivars, 53 R. raphanistrum individuals from six European populations and 104 California wild radish individuals from 11 populations covering its entire range throughout the state. We found that cultivated radish and R. raphanistrum shared no cpDNA haplotypes but that they both shared haplotypes with California wild radish, evidence for bidirectional hybridization between the progenitor species in the creation of the California lineage. We also found evidence that multiple cultivars and multiple European source populations contributed to the diversity of cpDNA haplotypes within California. Studies like this will continue to be important for our understanding of the origin of invasive populations and the mechanisms by which they succeed. 相似文献
19.
Elizabeth Moot O’Hern 《The Botanical review》1996,62(3):209-271
“Profiles of Pioneer Women Scientists: Katherine Esau” tells the story of a noted botanist, plant anatomist, and electron microscopist who was born in the Russian Ukraine (in 1898), forced to flee the Bolshevik Revolution with her family—her father a mayor of Ekaterinoslav under the Czar—to Germany, where she received a bachelor’s degree in agriculture, education she put to good use in America. Beginning in a sugarbeet field in Salinas, California, she progressed through the doctoral degree at the University of California at Davis (UC Davis) and there began her exceptional research on plant anatomy and plant viral diseases. Her textbookPlant Anatomy became known among college students as “Aunt Kitty’s Bible,” and all of her textbooks have gone into second, and some to third, editions. Transferring to the University of California at Santa Barbara (with its new Chancellor, V. I. Cheadle) only two years before retirement, she blossomed anew, producing some of her best work there and obtaining National Science Foundation support for a new electron microscope and other research funds through her 89th year. Katherine Esau started accruing awards and honors at a relatively early age (Faculty Research Lecturer at age 50, election to the National Academy of Sciences at 59) and has never stopped (the President’s Medal of Science at age 91, a UC Santa Barbara building named for her at age 93). It has been her good fortune to live to enjoy these honors. The short autobiography of her father, a truly enterprising engineer, is included here, as are the recollections of Celeste Turner Wright. Celeste, who arrived at UC Davis the same year as Katherine Esau, became an acclaimed poet, and chaired the English Department for many years. She has added a lively reminiscence of the days she and Katherine spent at UC Davis. The introduction to the book by one of Esau’s former graduate students, Ray Franklin Evert, himself a renowned plant pathologist, provides a heartfelt tribute to his greatly admired professor. 相似文献