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1.
Exhibit A: Objects of Intrigue. Museum of Anthropology, University of British Columbia, Vancouver, March 9, 1999–March 31, 2000.
Objects and Expressions: Celebrating the Collections of the Museum of Anthropology at the University of British Columbia. Vancouver: Museum of Anthropology, University of British Columbia, 1999.  相似文献   

2.
We previously obtained somaclonal variants of the important French fry processing cultivar Russet Burbank with significantly enhanced resistance to common scab disease. In this study we have shown the commercial merit of a proportion of these variants through comparison of relative yield and tuber quality with the parent cultivar Russet Burbank. Whilst we showed a weak negative correlation between tuber yield (as assessed by weight of tubers per plant) and relative disease resistance within selected variants, we identified several with equivalent yields to the parent cultivar. Furthermore, two disease-resistant variants (TC-RB8 and NZ-24B) consistently yielded more tuber mass than the parent. The majority of our Russet Burbank variants showed equivalent tuber quality characteristics (occurrence of defects, tuber specific gravity and dry matter content, and flesh colour) and cooking qualities (fry colour and presence of dark end defects) to the parent cultivar. Independent testing by a commercial French fry processor confirmed these quality characteristics. We present data demonstrating that highly common scab disease-resistant somaclonal variants of Russet Burbank have commercially acceptable tuber yield and quality characteristics, comparable to the industry standard and parent Russet Burbank cultivar. We also demonstrate the value of in vitro cell selection techniques for potato cultivar improvement.  相似文献   

3.
In addition to cultural practices, the application of the fungicide mefenoxam is an important disease management tactic used to control both pink rot and leak on potato tubers grown in the USA. Mefenoxam resistance has been identified in many of the potato growing regions, and therefore resistance management strategies are very important for retaining this fungicide as a tool to manage these storage rot diseases. The relationship between mefenoxam efficacy and cultivar susceptibility to pink rot and leak was assessed in post‐harvest inoculation studies. Mefenoxam was applied to potato (Solanum tuberosum) cultivars known to express varying levels of susceptibility to pink rot and leak caused by Phytophthora erythroseptica and Pythium ultimum, respectfully. Tubers harvested from plants treated with in‐furrow and foliar applications of mefenoxam were inoculated with isolates sensitive to the fungicide. Incidence and severity of both diseases ranged widely among cultivars. Russet Norkotah was the most susceptible to infection by P. erythroseptica, while cvs Pike and Atlantic were the most resistant. Cultivars Dark Red Norland, Russet Norkotah, Goldrush and Russet Burbank were most susceptible to infection by P. ultimum whereas Snowden was most resistant. Control of pink rot differed significantly among cultivars following mefenoxam treatment, ranging from 28% (cv. Goldrush) to 67% (cv. Snowden) and generally provided the greatest level of disease control on susceptible and moderately susceptible cultivars such as Russet Norkotah and Snowden, respectively. In contrast, the impact of mefenoxam on leak development was minimal and disease control did not differ significantly among the cultivars. The fungicide failed to control leak in the susceptible cvs Atlantic and Pike and control ranged from 1.7% to 5.2% in cvs Goldrush, Russet Norkotah, Dark Red Norland, Russet Burbank and Kennebec. The greatest level of leak control was achieved with the moderately resistant cv., Snowden, at 12.7%. Cultivars most likely to benefit from mefenoxam treatments should be targeted as part of a pink rot management programme. Judicious use of the fungicide, when matched with the level of cultivar susceptibility, may prove to be an efficient and effective approach to reduce infection rates and possibly manage mefenoxam resistance thereby maintaining longevity of the compound.  相似文献   

4.
Pathogenesis of M. chitwoodi associated with potato (Solanum tuberosura cv. Russet Burbank) followed a pattern characteristic of root-knot nematodes. Giant ceils developed in the phloem tissues of roots, stolons, and tubers and appeared to arise by hypertrophy and karyokinesis rather than cellular fusion. Gall formation was a function of parasite density and developed by hypertrophy of cortical cells. Brownish lesions which are symptomatic of tuber infection resulted from lignification of cortical cell walls in contact with egg matrix.  相似文献   

5.
The aim of this study was to determine if endophytic bacteria could contribute to cultivar specific interactions between red clover (Trifolium pratense L.) and potatoes (Solanum tuberosum L.) in crop rotations. Endophytic bacteria were isolated from the roots of four red clover cultivars (AC Charlie, Altaswede, Marino and Tempus) grown in the field. Populations of bacteria from each cultivar were similar. The most abundant genus was Rhizobium, but species of Curtobacterium, Pseudomonas, and Xanthomonas were common to all cultivars. Plantlets of two potato cultivars, Russet Burbank and Shepody, were inoculated individually with the seven bacterial isolates most frequently recovered from each red clover cultivar, and grown in Magenta vessels for 6 wk. Significant differences were found for plant height, and wet weights of roots, shoots and their total. Potato cultivars differed for root wet weight only, while red clover cultivar, as a source of bacteria, had a significant effect on all traits except plant height. Differences among bacteria were significant for all traits except shoot wet weight. There was a significant interaction of potato cultivar by red clover cultivar. The potato cultivar Russet Burbank did best with bacteria from the red clover cultivar, Marino; and Shepody, with bacteria from Altaswede.  相似文献   

6.
Second growth is an important physiological disorder of thepotato (Solanum tuberosum L.) plant. A model system to studysecond growth was developed using one-leaf cuttings. Photoperiod,temperature, decapitation and leaf removal treatments were carriedout on the plants from which the cuttings were taken and onthe cuttings themselves. Tuberized, one-leaf cuttings takenfrom moderately-induced plants and exposed to 35 °C afterleaf removal showed 95% second growth within 10 d after treatmentinitiation. Conditions that promoted second growth also reducedstarch and dry-matter content, even in tubers that did not developsecond growth. Cuttings, second growth, potato, Solanum tuberosum L, cv, Bintje, Solanum tuberosum L. cv., Désirée, Solanum tuberosum L. cv., Russet Burbank, tuberization, starch content, dry-matter, heat, photoperiod, decapitation, leaf removal  相似文献   

7.
Sixteen natural stands of Abies lasiocarpa (Hook.) Nutt. were sampled from British Columbia and Washington to investigate patterns of intraspecific variation in this species and to evaluate Hunt and von Rudloff's recognition of two species of subalpine fir. Principal components analysis and canonical variates analysis were performed separately on seed-cone data, needle morphology data, and needle flavonoid data. Analysis of cone data indicated no geographical patterning of populations, but eastern and western groups of populations were segregated in both the needle morphology and flavonoid analyses. With the exception of the Vancouver Island population, three geographic groups were discerned based on their needle morphology: 1) populations from the coastal mountains of British Columbia, 2) those from the Cascade Mountains of Washington, and 3) those from the eastern interior of British Columbia. Although the Vancouver Island population was grouped with the interior British Columbia populations based on needle morphology, it was similar to the other coastal populations based on flavonoid data. These inconsistent results among the three different types of taxonomic evidence underscore the need to consider a variety of traits when drawing taxonomic conclusions in Abies. Although the delineation of eastern and western groups is not wholly consistent for the different data sets, the results support recognition of coastal and interior varieties of subalpine fir.  相似文献   

8.
9.
Single female cuhures of Pratylenchus penetrans were established from soil and root samples collected from 10 geographically isolated locations in North America. The resultant isolates were used to evaluate nematode egression from and multiplication on roots of potato clones to distinguish intraspecific differences among isolates. The 10 nematode isolates were statistically separated into four groups based on percentage of nematodes that egressed from the P. penetrans-resistant potato done L 118-2. The Cornell (CR), Wisconsin (WI), Long Island (LI), and Adirondack (AD) isolates, selected as representative isolates of each of the four groups, exhibited 53%, 39%, 25%, and 10% egression from L118-2, respectively. Reproduction of these four isolates was measured on three potato cultivars (Russet Burbank, Butte, and Hudson) and two breeding lines (NY85 and L118-2). The LI and AD isolates reproduced well on all five potato clones. The CR isolate reproduced well on Russet Burbank and NY85 but significantly less on Butte, Hudson, and L118-2. Reproduction of the WI isolate was less than the LI and AD isolates but more than the CR isolate on all potato clones tested except Russet Burbank. Reproduction of the WI isolate on Russet Burbank was less than the other three isolates. Based on these results, four distinct intraspecific variants of P. penetrans are proposed: Cornell, Wisconsin, Long Island, and Adirondack.  相似文献   

10.
G. R. Gray  R. B. Marion 《CMAJ》1978,119(7):701-704
A number of varieties of thalassemia were found to be common in the Vancouver area and in other parts of British Columbia. Of 3117 patients whose blood samples were studied by hemoglobin electrophoresis at the Vancouver General Hospital between Jan 1, 1965 and June 30,1977, 813 had the beta-thalassemia trait, 18 had homozygous beta-thalassemia, 97 had alpha-thalassemia trait, 24 had hemoglobin H disease and 14 had miscellaneous variants. Eight patients had interactions of beta-thalassemia with hemoglobin S,C, D, O arab or Vancouver, and one patient had alpha thalassemia associated with hemoglobin Constant Spring. Twelve other variants were noted. They included hemoglobins B2, E, Q, GHsi Tsou, J Bangkok, British Columbia, KOLN, Lepore, Rampa, Tacoma, St. Claude and an unidentified alpha-chain variant.  相似文献   

11.
Cryptococcus gattii has recently emerged as a primary pathogen of humans and wild and domesticated animals in British Columbia, particularly on Vancouver Island. C. gattii infections are typically infections of the pulmonary and/or the central nervous system, and the incidence of infection in British Columbia is currently the highest reported globally. Prior to this emergence, the environmental distribution of and the extent of colonization by C. gattii in British Columbia were unknown. We characterized the environmental sources and potential determinants of colonization in British Columbia. C. gattii was isolated from tree surfaces, soil, air, freshwater, and seawater, and no seasonal prevalence was observed. The C. gattii concentrations in air samples were significantly higher during the warm, dry summer months, although potentially infectious propagules (<3.3 microm in diameter) were present throughout the year. Positive samples were obtained from many different areas of British Columbia, and some locations were colonization "hot spots." C. gattii was generally isolated from acidic soil, and geographic differences in soil pH may influence the extent of colonization. C. gattii soil colonization also was associated with low moisture and low organic carbon contents. Most of the C. gattii isolates recovered belonged to the VGIIa genetic subtype; however, sympatric colonization by the VGIIb strain was observed at most locations. At one sampling site, VGIIa, VGIIb, VGI, and the Cryptococcus neoformans serotype AD hybrid all were coisolated. Our findings indicate extensive colonization by C. gattii within British Columbia and highlight an expansion of the ecological niche of this pathogen.  相似文献   

12.
Role of Endogenous Abscisic Acid in Potato Microtuber Dormancy   总被引:8,自引:1,他引:7       下载免费PDF全文
Potato (Solanum tuberosum L. cv Russet Burbank) microtubers generated in vitro from single-node explants contained substantial amounts (approximately 250 pmol/g fresh weight) of free abscisic acid (ABA) and were completely dormant for a minimum of 12 weeks. Microtubers that developed in the presence of 10 [mu]M fluridone (FLD) contained considerably reduced amounts (approximately 5-25 pmol/g fresh weight) of free ABA and exhibited a precocious loss of dormancy. Inclusion of exogenous racemic ABA in the FLD-containing medium suppressed the premature sprouting of these microtubers in a dose-dependent manner. At a concentration of 50 [mu]M, exogenous ABA restored internal ABA levels to control values and completely inhibited FLD-induced precocious sprouting. Exogenous jasmonic acid was ineffective in suppressing FLD-induced sprouting. Application of FLD to preformed, fully dormant microtubers also resulted in a reduction in internal ABA content and precocious sprouting. These results indicate that endogenous ABA is essential for the induction and maintenance of potato microtuber dormancy.  相似文献   

13.
Callus derived from Lemhi Russet and Russet Burbank tuber tissue was incubated at 20°C and 30°C on a high sucrose medium for starch-formation and subjected to simulated storage and reconditioning treatments at 5°C and 25°C after transfer of the callus to a medium without a carbon source. Percent dry weight of callus from both cultivars averaged about 21% after starch formation and 5% after storage and reconditioning treatments. Total sugars were higher in callus incubated on the starch forming treatment. Lemhi Russet callus contained predominantly reducing sugars, while Russet Burbank callus contained mostly non-reducing sugars. Total sugar content was generally lower for both cultivars after the storage and reconditioning treatment in callus after starch formation at 20°C. Starch content was generally higher in Lemhi Russet tissue. After starch formation at 20°C Lemhi Russet had higher starch after the storage and reconditioning treatment than tissue from 30°C, while the opposite trend was found in Russet Burbank tissue. Total protein declined in Russet Burbank tissue during the storage and reconditioning treatment regardless of prior incubation conditions, while this decline only occurred in Lemhi Russet tissue initially incubated at 30°C during the starch formation treatment. In tissue of both cultivars, ATP- and PPi-dependent phosphofructokinase activities were inversely proportional to total sugar concentrations, while in RB callus ADP glucose pyrophosphorylase activities were proportional to starch content.Research Paper 91B1 of the Idaho Agricultural Experiment Station.  相似文献   

14.
Cryptococcus gattii causes life-threatening disease in otherwise healthy hosts and to a lesser extent in immunocompromised hosts. The highest incidence for this disease is on Vancouver Island, Canada, where an outbreak is expanding into neighboring regions including mainland British Columbia and the United States. This outbreak is caused predominantly by C. gattii molecular type VGII, specifically VGIIa/major. In addition, a novel genotype, VGIIc, has emerged in Oregon and is now a major source of illness in the region. Through molecular epidemiology and population analysis of MLST and VNTR markers, we show that the VGIIc group is clonal and hypothesize it arose recently. The VGIIa/IIc outbreak lineages are sexually fertile and studies support ongoing recombination in the global VGII population. This illustrates two hallmarks of emerging outbreaks: high clonality and the emergence of novel genotypes via recombination. In macrophage and murine infections, the novel VGIIc genotype and VGIIa/major isolates from the United States are highly virulent compared to similar non-outbreak VGIIa/major-related isolates. Combined MLST-VNTR analysis distinguishes clonal expansion of the VGIIa/major outbreak genotype from related but distinguishable less-virulent genotypes isolated from other geographic regions. Our evidence documents emerging hypervirulent genotypes in the United States that may expand further and provides insight into the possible molecular and geographic origins of the outbreak.  相似文献   

15.
Molecular analyses of the mitochondrial genome using restriction fragment length polymorphism (RFLP) were utilized to determine the existence of discrete populations of the tidepool sculpin Oligocottus maculosus from the Barkley Sound region of south-western Vancouver Island, British Columbia. Fifty-five haplotypes were found with three haplotypes making up 38, 16 and 8% of the total sample, respectively. Within individual tidepools, haplotype diversity ranged from 0·30 to 0·92, but haplotypes were typically closely related to one another (nucleotide diversity ranged from 0·0004 to 0·005). The majority of haplotype variation (96–97%) was located within tidepools, but a significant amount of variation ( c . 3–4%) was detected among tidepools within single islands. By contrast, there was no significant differentiation among islands or between samples from the Barkley Sound area and a single sample from north-eastern Vancouver Island. The results suggest a low level of population structure within the sample area and that the distribution of haplotypes and haplotype divergences represents a demographic expansion from a single ancestral lineage beginning between 300 000 and 1 000 000 years ago. The low level of population subdivision resolved suggests that despite their ecological specialization in tidepool habitats, tidepool sculpins are influenced by demographic and genetic processes that operate on spatial scales much larger than single tidepools or islands.  相似文献   

16.
Mesophyll cell protoplasts were isolated from potato (Solanum tuberosum L. cv. Russet Burbank) leaves and induced to proliferate in culture. Protoplast division was observed only among preparations isolated from plants previously conditioned under short periods of low intensity illumination. Sustained growth and development of protoplast-derived calli (p-calli) occurred when they were maintained on defined media at 24 C under 500 lux lighting. Shoot bud development within p-calli was controlled by a number of factors including light, temperature, basic medium composition, nature and source of phytohormones, the continued presence of an osmoticum, low concentrations of a utilizable carbohydrate, and the developmental stage of the p-callus.  相似文献   

17.
Geographic variation in minisatellite DNA variation was examined in 18 stocks of coho salmon Oncorhynchus kisutch from British Columbia and three stocks from Kamchatka or Western Alaska. Genomic DNA was restricted with Mbo I or Hae III and hybridized with two minisatellite probes (p Ssa -A34, Ots PBS-1). Allele frequencies and DNA band counts derived from the two probes were combined with band counts from the probe Ssa to show a regional stock structure. In British Columbia, stocks from the Fraser River were distinct from those on Vancouver Island, and all were differentiated from those on the mainland of British Columbia. Average heterozygosity at the Ssa -A34 locus was 71%. Compared with a previous study of British Columbia coho salmon population structure in which variation at 26 allozyme loci was examined, greater population differentiation and higher heterozygosity were observed at minisatellite loci. Estimated stock compositions of simulated mixtures of fishery samples from British Columbia stocks were accurate and precise, with the potential of identifying stocks within the drainage basin of a major river, the Fraser River. Minisatellite DNA variation may provide accurate and precise estimates of stock composition in actual fishery applications, and has the potential of identifying individual fish to region or stock of origin.  相似文献   

18.
Twelve years'' experience in providing summer employment for students in official health agencies in British Columbia is reviewed and a two-week orientation course given prior to employment in 1964 is described. In the program, which provides experience in teaching, research and community service, a total of 43 students have been employed. Students seeking this type of employment and accepted for it tend to have high academic standing. They prefer employment in or near Vancouver irrespective of their original home location. Two main employers have been available: specialized agencies in metropolitan Vancouver, or “rural” health units. Students serving in health units showed a strong tendency to enter general practice after graduation. Urban experience tended to lead to specialization.  相似文献   

19.
A unique provincial medical library service has been established in British Columbia. Under the direction of professional librarians, the central library in Vancouver is building an extensive, largely clinical collection while 30 smaller branch libraries in hospitals throughout the province are establishing basic, up-to-date collections. Financial support comes from an annual fee of $25.00 per doctor paid to the College of Physicians and Surgeons of British Columbia. Photoduplication, mail and telephone services meet many reference needs. Reading is vital to continuing medical education. The library works closely with the University of British Columbia''s Department of Continuing Medical Education to bring current medical knowledge to every doctor in British Columbia.  相似文献   

20.
Opportunities for selfing through geitonogamy are possible if more than one flower within the same clone, inflorescence, or floral unit is open at the same time. In a total of 200 inflorescences in two natural populations of Iris versicolor, flowers were observed and classified daily on the basis of anther dehiscence and stigma receptivity. Analysis of the flowering phenology demonstrated that (1) protandry limits opportunities for autogamy, (2) flowers mature sequentially within a floral unit (defined as a cluster of flowers borne on a single branch within an inflorescence), preventing the opportunity for geitonogamous fertilization between flowers of the same floral unit, and (3) 77% of all flowers had no opportunity to be pollinated by another flower within the same inflorescence. Both the number and the proportion of flowers with opportunities for geitonogamy increased with the number of flowers open in each population, and opportunities for geitonogamy also increased with the number of floral units within inflorescences. These morphological and phenological controls suggest that when selfing occurs in this species, it is most likely to occur between flowers on different inflorescences within the same clone. Since the organization of whole inflorescences in space is determined primarily by rhizome placement, clonal architecture may play an important role in mating system regulation in this species.  相似文献   

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