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81.
美国黑核桃SSR反应体系优化 总被引:2,自引:1,他引:1
优化SSR-PCR反应体系是黑核桃(Juglans nigra L.)SSR基因鉴定和群体遗传等研究的基础。本研究通过对PCR反应中Mg2+浓度、牛血清白蛋白(Bovine Serum Albumin,BSA)浓度、Taq聚合酶用量、dNTPs浓度、引物浓度和模板DNA量的组合以及PCR程序组合试验,确定了黑核桃SSR的最佳反应体系,即在10 μL的PCR反应体系中,含10 ng模板DNA,0.1 mg·mL-1牛血清蛋白(BSA),0.25 mmol·L-1 dNTPs,1.5 mmol·L-1 Mg2+ 1 μL 10X Taq DNA聚合酶反应缓冲液,0.5 U Taq聚合酶,1.0 mmol·L-1单对引物(0.5 mmol·L-13对引物)。SSR-PCR反应扩增程序为:94℃变性3 min;93℃变性15 s,50℃或者53.5℃退火1 min,72℃延伸30 s,32个循环;72℃后延伸10 min,置4℃保存。利用此反应体系对黑核桃进行PCR扩增并电泳检测,其结果清晰、稳定、可靠,适合进一步对黑核桃群体遗传、基因型鉴定和分子生态研究。 相似文献
82.
Forgách P Bakonyi T Tapaszti Z Nowotny N Rusvai M 《Journal of invertebrate pathology》2008,98(2):235-238
A survey on the occurrence of six honeybee-pathogenic viruses was carried out using one-step RT-PCR assays. Samples were collected between 1999 and 2004 in 52 Hungarian apiaries located in different regions of the country. The results of the assays on samples of adult honeybees and Varroa destructor mites were compared to similar surveys from France and Austria. The study demonstrates geographical differences in the prevalence of honeybee viruses between Hungary and the older EU member states. The results could serve as a basis for monitoring further changes in the distribution of honeybee viruses in Europe. 相似文献
83.
ROBERT W. KLAVER JONATHAN A. JENKS CHRISTOPHER S. DEPERNO STEVEN L. GRIFFIN 《The Journal of wildlife management》2008,72(2):343-353
ABSTRACT Delineating populations is critical for understanding population dynamics and managing habitats. Our objective was to delineate subpopulations of migratory female white-tailed deer (Odocoileus virginianus) in the central Black Hills, South Dakota and Wyoming, USA, on summer and winter ranges. We used fuzzy classification to assign radiocollared deer to subpopulations based on spatial location, characterized subpopulations by trapping sites, and explored relationships among survival of subpopulations and habitat variables. In winter, Kaplan-Meier estimates for subpopulations indicated 2 groups: high (S = 0.991 ± 0.005 [x̄ ± SE]) and low (S = 0.968 ± 0.007) weekly survivorship. Survivorship increased with basal area per hectare of trees, average diameter at breast height of trees, percent cover of slash, and total point-center quarter distance of trees. Cover of grass and forbs were less for the high survivorship than the lower survivorship group. In summer, deer were spaced apart with mixed associations among subpopulations. Habitat manipulations that promote or maintain large trees (i.e., basal area = 14.8 m2/ha and average dbh of trees = 8.3 cm) would seem to improve adult survival of deer in winter. 相似文献
84.
To locate quantitative trait loci (QTL) for intramuscular fat deposition (marbling) in a local population of Japanese Black cattle, we performed a genome scan using a paternal half-sib family of Bull A. A marbling QTL was mapped in the region flanked by DIK0079 (20.7 cM) and TGLA303 (39.3 cM) on bovine chromosome (BTA) 7, affecting 5.0% of the total family variance. Haplotype analysis of the QTL region revealed that the marbling-increasing Q allele was transmitted from the dam. On the other hand, Bull B, a maternal half-sib of Bull A, did not receive the Q allele from its dam, based on the following findings: (i) a marbling QTL on BTA7 was not detected in the Bull B paternal half-sib family; (ii) recombination between DIK0079 (20.7 cM) and RM006 (25.4 cM) in the QTL region was observed in the maternal chromosome of Bull B; and (iii) the Q -harbouring steers from Bull A exhibited significantly higher marbling than the steers from Bull B and the remaining steers from Bull A. To precisely compare the maternal chromosomes of both bulls, we constructed a bacterial artificial chromosome contig covering the region between DIK0079 and RM006 and developed DNA markers. The recombination occurred between DIK8042 and DIK8044 , indicating that the marbling QTL was in a 2.9-cM region flanked by DIK0079 and DIK8044 . 相似文献
85.
Lindsey Nielsen Dawn Meehan-Meola Annelisa Kilbourn Acacia Alcivar-Warren 《Conservation Genetics》2008,9(1):239-242
As the population sizes of the black and white rhinoceroses continues to decline, more efforts are needed in multiple areas
to help with the conservation efforts. One area being explored is the use of genetic diversity information to aid conservation
decisions. In this study, we designed 21 microsatellite primers for white and black rhinoceroses, 16 and 17 of which amplified
bands in the white and black rhinoceros, respectively. Out of these primers all 16 were polymorphic in the white rhinoceros
and 12 of the 17 were polymorphic in the black rhinoceros. The mean number of alleles was 3.31 and 2.12, the expected heterozygosities
were 0.420 and 0.372, and the observed heterozygosities were 0.436 and 0.322 for the white and black rhinoceroses, respectively.
Seven of the primers produced different allele sizes and variations that distinguished between black and white rhinoceroses.
Further genetic analyses with larger wild population sample sizes and markers are recommended to obtain a better understanding
of the genetic structure of the black and white rhinoceros populations in order to be useful in the conservation efforts of
these critically endangered species.
A. Kilbourn—In memoriam. 相似文献
86.
Tim Rixen Antje Baum Thomas Pohlmann Wolfgang Balzer Joko Samiaji Christine Jose 《Biogeochemistry》2008,90(2):129-140
The Siak is a black water river in central Sumatra, Indonesia, which owes its brown color to dissolved organic matter (DOM)
leached from surrounding, heavily disturbed peat soils. The dissolved organic carbon (DOC) concentrations measured during
five expeditions in the Siak between 2004 and 2006 are among the highest reported world wide. The DOM decomposition appeared
to be a main factor influencing the oxygen concentration in the Siak which showed values down to 12 μmol l−1. Results derived from a box-diffusion model indicated that in addition to the DOC concentration and the associated DOM decomposition
the water-depth also plays a crucial role in regulating the oxygen levels in the river because of its impact on the turbulence
in the aquatic boundary layer and the surface/volume ratio of water in the river. Model results imply furthermore that a reduced
water-depth could counteract an increased oxygen consumption caused by an enhanced DOM leaching during the transition from
dry to wet periods. This buffer mechanism seems to be close to its limits as indicated by sensitivity studies which showed
in line with measured data that an increase of the DOC concentrations by ~15% could already lead to anoxic conditions in the
Siak. This emphasizes the sensitivity of the Siak against further peat soil degradation, which is assumed to increase DOC
concentrations in the rivers. 相似文献
87.
Fuying?Ma Zheng?Xiong Yubin?Zheng Xiaochen?Yu Xiaoyu?ZhangEmail author 《World journal of microbiology & biotechnology》2008,24(11):2627-2632
A repeated batch operation is developed for the treatment of alkaline pulp black liquor, through a process of biological acidification
precipitation of lignin using brown rot fungus Fomitopsis sp. IMER2. The results showed that COD and color removal of black liquor was dependent on the biomass concentration, pH decrease
and initial COD. Based on these results, the repeated batch process was successfully carried out 12 times over 36 days in
an air bubble column bioreactor. The average reduction of COD and color was approximately 40% and 70%, respectively. 相似文献
88.
SUMMARY: State and federal natural resource management agencies often collect age-structured harvest data. These data represent finite realizations of stochastic demographic and sampling processes and have long been used by biologists to infer population trends. However, different sources of data have been combined in ad hoc ways and these methods usually failed to incorporate sampling error. In this article, we propose a "hidden process" (or state-space) model for estimating abundance, survival, recovery rate, and recruitment from age-at-harvest data that incorporate both demographic and sampling stochasticity. To this end, a likelihood for age-at-harvest data is developed by embedding a population dynamics model within a model for the sampling process. Under this framework, the identification of abundance parameters can be achieved by conducting a joint analysis with an auxiliary data set. We illustrate this approach by conducting a Bayesian analysis of age-at-harvest and mark-recovery data from black bears (Ursus americanus) in Pennsylvania. Using a set of reasonable prior distributions, we demonstrate a substantial increase in precision when posterior summaries of abundance are compared to a bias-corrected Lincoln-Petersen estimator. Because demographic processes link consecutive abundance estimates, we also obtain a more realistic biological picture of annual changes in abundance. Because age-at-harvest data are often readily obtained, we argue that this type of analysis provides a valuable strategy for wildlife population monitoring. 相似文献
89.
长期培肥黑土微生物量磷动态变化及影响因素 总被引:20,自引:5,他引:15
长期采用两种不同量有机肥(M2、M4)、化肥(NPK)方式培肥黑土,研究微生物量P在作物生长季动态变化.结果表明。施用有机肥微生物量P显著高于施用化肥(NPK)和不施肥(CK),微生物量P分别为M48.75~47.68mg·kg^-1,M2 3.02~37.16mg·kg^-1,NPK1.59~10.62mg·kg^-1,CK0.76~6.74mg·kg^-1之间,波动性较大.M4、M2处理微生物量P最大值出现在抽雄吐丝期,NPK、CK处理最大值出现在大喇叭口期;施肥数量和种类不同所引起的黑土微生物量P的差异并未因季节变化及玉米生育时期影响而明显改变.微生物量P的动态变化与绝大多数黑土生物、理化特性指标的动态变化没有显著的相关性;微生物量P与黑土生物、理化特性(除全钾外),植物氮、磷、钾含量有极显著的正相关关系,与黑土含水量呈显著正相关关系. 相似文献
90.
An Ethnographic Filmflam: Giving Gifts, Doing Research, and Videotaping the Native Subject/Object 总被引:1,自引:0,他引:1
JOHN L. JACKSON JR. 《American anthropologist》2004,106(1):32-42
Using the discussion of self-reflexivity as an organizing principle, this article examines how mobilizing digital video technology during fieldwork opens up empirical and theoretical space for reconceptualizing the relationship between anthropologists and informants. Placing the field of visual anthropology into critical conversation with long-standing theoretical arguments about the objectivist limitations of native anthropologists, I argue that the slipperiness of nativity as an anthropological designation helps to provide analytical tools for examining filmmaking as a kind of gift-giving process between native ethnographic filmmakers and the subjects of their films. This article highlights some of the ways in which my own filmic and videographic exploits in Harlem, New York, mark integral connections between seeing and being the proverbial other, probing social exchanges predicated on the usefulness of low-budget digital technology as a means of fostering politically and epistemologically valuable ethnographic collaborations. 相似文献