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High levels of genetic diversity throughout the range of the Portuguese wheat landrace 'Barbela' 总被引:5,自引:0,他引:5
Ribeiro-Carvalho C Guedes-Pinto H Igrejas G Stephenson P Schwarzacher T Heslop-Harrison JS 《Annals of botany》2004,94(5):699-705
BACKGROUND AND AIMS: Landrace populations represent an important intra-crop reservoir of biodiversity and source of novel gene alleles for use in breeding programmes. Here the aim was to measure the diversity of a wheat landrace, 'Barbela', from the north of Portugal. METHODS: DNA was extracted from 59 accessions of Barbela collected across its geographical range. Diversity was measured by microsatellite length polymorphisms using 27 primer pairs amplifying 34 polymorphic microsatellite loci. KEY RESULTS: High levels of polymorphism were found, with an average polymorphism information content of 0.52; an average of 4.77 alleles (range 2-11) were present at each locus, and half of these loci showed an additional allele in the reference variety 'Chinese Spring'. CONCLUSIONS: 'Barbela' is maintained from seeds collected by farmers, but it maintains high allelic variation, and no groupings of accessions were detected when analysed by geographical region, farm or climate, indicating that the wheat landrace is a homogeneous entity. The diversity within the farmer-maintained landrace demonstrates the importance of characterization and maintenance of landrace collections before valuable genetic combinations are lost as uniform commercial crops are introduced. 相似文献
95.
Timothy M Coskran Daniel Morton Frank S Menniti Wendy O Adamowicz Robin J Kleiman Anne M Ryan Christine A Strick Christopher J Schmidt Diane T Stephenson 《The journal of histochemistry and cytochemistry》2006,54(11):1205-1213
A monoclonal antibody directed against the amino terminal of rat phosphodiesterase 10A (PDE10A) was used to localize PDE10A in multiple central nervous system (CNS) and peripheral tissues from mouse, rat, dog, cynomolgus macaque, and human. PDE10A immunoreactivity is strongly expressed in the CNS of these species with limited expression in peripheral tissues. Within the brain, strong immunoreactivity is present in both neuronal cell bodies and neuropil of the striatum, in striatonigral and striatopallidal white matter tracks, and in the substantia nigra and globus pallidus. Outside the brain, PDE10A immunoreactivity is less intense, and distribution is limited to few tissues such as the testis, epididymal sperm, and enteric ganglia. These data demonstrate that PDE10A is an evolutionarily conserved phosphodiesterase highly expressed in the brain but with restricted distribution in the periphery in multiple mammalian species. 相似文献
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In previous studies, we have investigated the strength of self-incompatibility (SI) in Solanum carolinense, a highly successful weed with a fully functional SI system that inhabits early successional and other disturbed habitats.
We have found that the SI response in S. carolinense is a plastic trait—its strength being affected by the age of the flowers, and the presence of developing fruits and that
there are genetic differences among families in their self-fertility. However, in species with a fully functional SI response,
selfing would not be that common. As a result, deleterious recessives scattered though the genome of horsenettle are only
occasionally exposed to selection. It has been suggested that deleterious recessives accumulate near S-alleles in strong SI species because the S-locus is located in a non-recombining region of the genome and because strong S-alleles are never in the homozygous state, thus sheltering some of the genetic load near the S-locus from selection. We performed a series of laboratory and greenhouse experiments to determine the extent to which sheltered
load adds to the overall magnitude of inbreeding depression in horsenettle. Specifically, we amplified and sequenced the S-alleles from 16 genets collected from a large population in Pennsylvania and performed a series of controlled self-pollinations.
We then grew the selfed progeny in the greenhouse; recorded various measures of growth and reproductive output; and amplified
and sequenced their S-allele(s). We found that the heterozygous progeny of self-pollinations produce more flowers and have a greater ability to
set both self and cross seed than S-homozygous progeny. We also found evidence of variation in the magnitude of load among S-alleles. These results suggest that sheltered load might slow the fixation of weak (partially compatible) S-alleles in this population, thus adding to the maintenance of a mixed mating system rather than leading to the fixation of
the selfing alleles. 相似文献
98.
Amanda Wendt Rob Stephenson Melissa Young Amy Webb-Girard Carol Hogue Usha Ramakrishnan Reynaldo Martorell 《PloS one》2015,10(3)
Background
In Bihar, India, high maternal anemia prevalence and low iron and folic acid supplement (IFA) receipt and consumption have continued over time despite universal IFA distribution and counseling during pregnancy.Purpose
To examine individual and facility-level determinants of IFA receipt and consumption among pregnant women in rural Bihar, India.Methods
Using District Level Household Survey (2007–08) data, multilevel modeling was conducted to examine the determinants of two outcomes: IFA receipt (any IFA receipt vs. none) and IFA consumption (≥90 days vs. <90 days). Individual-level and facility-level factors were included. Factor analysis was utilized to construct antenatal care (ANC) quality and health sub-center (HSC) capacity variables.Results
Overall, 37% of women received any IFA during their last pregnancy. Of those, 24% consumed IFA for 90 or more days. Women were more likely to receive any IFA when they received additional ANC services and counseling, and attended ANC earlier and more frequently. Significant interactions were found between ANC quality factors (odds ratio (OR): 0.37, 95% confidence interval (CI): 0.25, 0.56) and between ANC services and ANC timing and frequency (OR: 0.68, 95% CI: 0.56, 0.82). No HSC factors were significantly associated with IFA receipt. Women were more likely to consume IFA for ≥90 days if they attended at least 4 ANC check-ups and received more ANC services. IFA supply at the HSC (OR: 1.37, 95% CI: 1.04, 1.82) was also significantly associated with IFA consumption.Conclusions
Our findings indicate that individual and ANC factors (timing, frequency, and quality) play a key role in facilitating IFA receipt and consumption. Although HSC capacity factors were not found to influence our outcomes, significant variation at the facility level indicates unmeasured factors that could be important to address in future interventions. 相似文献99.
Ameeta S. Kalokhe Ratnaprabha R. Potdar Rob Stephenson Kristin L. Dunkle Anuradha Paranjape Carlos del Rio Seema Sahay 《PloS one》2015,10(3)
Domestic violence (DV) is reported by 40% of married women in India and associated with substantial morbidity. An operational research definition is therefore needed to enhance understanding of DV epidemiology in India and inform DV interventions and measures. To arrive at a culturally-tailored definition, we aimed to better understand how definitions provided by the World Health Organization and the 2005 India Protection of Women from Domestic Violence Act match the perceptions of behaviors constituting DV among the Indian community. Between September 2012 and January 2013, 16 key informant interviews with experts in DV and family counseling and 2 gender-concordant focus groups of lay community members were conducted in Pune, India to understand community perceptions of the definition of DV, perpetrators of DV, and examples of DV encountered by married women in Pune, India. Several key themes emerged regarding behaviors and acts constituting DV including 1) the exertion of control over a woman’s reproductive decision-making, mobility, socializing with family and friends, finances, and access to food and nutrition, 2) the widespread acceptance of sexual abuse and the influences of affluence on sexual DV manifestations, 3) the shaping of physical abuse experiences by readily-available tools and the presence of witnesses, 4) psychological abuse for infertility, dowry, and girl-children, and 5) the perpetration of DV by the husband and other members of his family. Findings support the need for a culturally-tailored operational definition that expands on the WHO surveillance definition to inform the development of more effective DV intervention strategies and measures. 相似文献
100.
J Groffen N Heisterkamp N Spurr S Dana J J Wasmuth J R Stephenson 《Nucleic acids research》1983,11(18):6331-6339
A molecular probe was prepared with specificity for the human cellular homologue of transforming sequences represented within the McDonough strain of feline sarcoma virus (v-fms). By analysis of a series of mouse-human somatic cell hybrids containing variable complements of human chromosomes it was possible to assign this human oncogene, designated c-fms, to chromosome 5. Regional localization of c-fms to band q34 on chromosome 5 was accomplished by analysis of Chinese hamster-human cell hybrids containing as their only human components, terminal and interstitial deleted forms of chromosome 5. The localization of c-fms to chromosome 5 (q34) is of interest in view of reports of a specific, apparently interstitial, deletion involving approximately two thirds of the q arm of chromosome 5 in acute myelogenous leukemia cells. 相似文献