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121.
A pyramided FHB resistance line of wheat (WSY) was previously developed from three FHB resistant cultivars (Sumai 3, Wangshuibai,
and Nobeokabouzu) in the Jiangsu Academy of Agricultural Sciences, China. In the present study, we analyzed the genetic relationship
between WSY and the three parental cultivars using DNA markers in order to clarify how many and which resistance genes had
accumulated in WSY. We analyzed 282 DNA markers from the 21 wheat chromosomes. WSY was found to include different chromosome
regions that harbored putative FHB QTLs of the three parental germplasm. Haplotypes of DNA markers on these QTL regions revealed
that the 1BL, 2BL, 5AS, and 7AL QTL regions were from Sumai 3, the 2AS, 2DS, 3AS, and 6BS QTL regions were from Wangshuibai,
and the 3BS QTL region was from Nobeokabouzu. This study showed that different resistance genes from the different resistant
germplasm had indeed accumulated in WSY. WSY is a potential resistant resource for FHB resistance in wheat breeding programs. 相似文献
122.
Marie Helleberg Bamenla Q Goka Bartholomew D Akanmori George Obeng-Adjei Onike Rodriques Jorgen AL Kurtzhals 《Malaria journal》2005,4(1):1-7
In sub-Saharan Africa the highest overlap between malaria and HIV infections occurs in female adolescents. Yet control activities for these infections are directed to different target groups, using disparate channels. This reflects the lack of priority given to adolescents and the absence of an accepted framework for delivering health and health-related interventions to this high-risk group. In this paper it is argued that female adolescents require a continuum of care for malaria and HIV – prior to conception, during and after pregnancy and that this should be provided through adolescent services. The evidence for this conclusion is presented. A number of African countries are commencing to formulate and implement adolescent-friendly policies and services and disease control programs for malaria and HIV will need to locate their interventions within such programs to ensure widespread coverage of this important target group. Failure to prioritize adolescent health in this way will seriously limit the success of disease control programs for malaria and HIV prevention. 相似文献
123.
Cultivated plant species diversity in home gardens of an Amazonian peasant village in Northeastern Peru 总被引:1,自引:0,他引:1
Research on agrobiodiversity points to the importance of home gardens in situ conservation, yet few studies to date explicate
the origins and dynamics of plant species diversity. In this paper, we examine inter-household variations in cultivated plant
species diversity among house gardens in a traditional peasant community, near Iquitos, Peru. In-depth household interviews
(n = 24) and garden/field surveys reveal that home gardens are clearly the site of highest plant diversity in farmers’ field
portfolios, and that substantial differences exist in garden composition, plant diversity, and the sources of garden planting
material across households. Statistical analyses indicate that home garden diversity is related strongly to specific garden
characteristics, household socioeconomic features, and access to planting material including seeds, cuttings, and suckers.
The role and implications of differential access to planting material in the development and maintenance of crop species diversity
is signaled as an important theme for future study in economic botany. 相似文献
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125.
T. Yamamoto T. Kimura Y. Sawamura K. Kotobuki Y. Ban T. Hayashi N. Matsuta 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2001,102(6-7):865-870
Apple simple sequence repeats (SSRs) were intergenerically applied to the characterization of 36 pear accessions, including
19 Japanese pears (Pyrus pyrifolia), 7 Chinese pears (P. bretschneideri, P. ussuriensis), 5 European pears (P. communis), 3 wild relatives (P. calleryana), and 2 hybrids between P. pyrifolia and P. communis. All of the tested SSR primers derived from apple produced discrete amplified fragments in all pear accessions. Nucleotide
repeats were detected in the amplified bands by both Southern blot and sequencing analysis, and nucleotide sequences of pear
were compared with those of apple. The differences in fragment size among pear or between pear and apple were, in many cases,
due to the differences in repeat number. Interestingly, the DNA sequence of flanking regions in apple was highly conserved
in pear. Hybrids from P. pyrifolia×P. communis showed one fragment inherited from each parent in all scorable cases, which suggested that each primer pair amplified fragments
originating from the same locus. A total of 79 alleles were detected from seven SSR loci in pear, and all pear varieties except
for the mutants could be differentiated. In conclusion, SSRs isolated from apple are highly conserved in pear and could be
utilized as DNA markers in the latter genus.
Received: 17 July 2000 / Accepted: 22 September 2000 相似文献
126.
T. Yamamoto T. Kimura M. Shoda Y. Ban T. Hayashi N. Matsuta 《Molecular ecology resources》2002,2(1):14-16
Thirteen polymorphic microsatellite loci were developed in the Japanese pear (Pyrus pyrifolia Nakai) by using an enriched genomic library. The obtained microsatellite loci showed a high degree of polymorphism in the Japanese pear with 3–6 alleles per locus. The average values of observed and expected heterozygosities among these 13 loci were 0.69 and 0.71, respectively. Ten microsatellites could successfully amplify loci in the European pear (Pyrus communis L.), which were highly polymorphic as well. 相似文献
127.
Martin Scaal Felicitas Pr?ls Ernst Martin Füchtbauer Ketan Patel Christoph Hornik Thomas K?hler Bodo Christ Beate Brand-Saberi 《Mechanisms of development》2002,110(1-2):51-60
Bone morphogenetic protein (BMP) signaling is known to be involved in multiple inductive events during embryogenesis including the development of amniote skin. Here, we demonstrate that early application of BMP-2 to the lateral trunk of chick embryos induces the formation of dense dermis, which is competent to participate in feather development. We show that BMPs induce the dermis markers Msx-1 and cDermo-1 and lead to dermal proliferation, to expression of β-catenin, and eventually to the formation of ectopic feather tracts in originally featherless regions of chick skin. Moreover, we present a detailed analysis of cDermo-1 expression during early feather development. The data implicate that cDermo-1 is located downstream of BMP in a signaling pathway that leads to condensation of dermal cells. The roles of BMP and cDermo-1 during development of dermis and feather primordia are discussed. 相似文献
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