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81.
Yang YuZhe 《保鲜与加工》2005,(3):5
By review of region study in recent development of history science, geography and Sciences of Human Settlements, this paper points out that material collecting without interrelated analyzing as well as focusing on main question and assumption without enough argumentation are main problems in this field now. The method renovation & combination with related subjects are discussed, this paper concludes that strengthen interdisciplinary study with Geography is a key issue in the future development of region study in Sciences of Human Settlements and possible approach to "technical development' and "humanity concern'. 相似文献
82.
LIU Xin-rong~ 《保鲜与加工》2004,(3):32-36
Based on the experimental study of the compound rock's behavior at rock salt's over-layer under single compression and tri-axial compression condition, the basic mechanical properties of the rock have been obtained. It could serve as reference to research work and production. 相似文献
83.
84.
Summary Six Festuca rubra populations from Europe and Scandinavia were studied for variation at three isozyme loci; phosphoglucoisomerase (PGI-2), glutamate oxaloacetate transaminase (GOT-3) and superoxide dismutase (SOD-1). Seven alleles were found at the Pgi-2 locus, four at the Got-3 locus and five at the Sod-1 locus. Most plants were heterozygous and up to five alleles were found in the same plant at the Pgi-2 locus. Each population could be distinguished by the presence or absence of certain alleles or by differences in the frequencies of the alleles present. Values for the Shannon diversity index were calculated which showed that there was considerable heterogeneity both within and between loci. In general, 53% of this diversity could be attributed to within population variation. 相似文献
85.
对杂交油菜种子进行科学的质量分级,是当前种子生产和质量管理方面急待解决的问题,通过试验研究认为,对于育成时间短,应用面积小的杂种组合进行种子质量分级,条件尚不成熟。但对推广时间长。面积大,质量比较稳定的质不育“三系”和核不育“两系”杂交组合制定种子质量标准则是可行的。该文依据试验结果,探讨了质不育“三系”和核不育“两系”油菜杂交种种子质量的分级问题。 相似文献
86.
我国农产品加工业的整体实力还比较薄弱,质量还有待提升,带动作用还应进一步增强,这些问题的解决不能光靠农产品加工业本身,还需要国家财政的扶持。从公共财政、财政支农、农产品加工业的产业特点等方面探讨了公共财政扶持农产品加工业的理论依据,并提出了相关的政策建议与措施。 相似文献
87.
Isolation and characterization of microsatellites in Bambusa arundinacea and cross species amplification in other bamboos 总被引:3,自引:0,他引:3
Isolation and characterization of microsatellites was analysed in Bambusa arundinacea and cross species amplification studied in other bamboos. Microsatellites, tandem repeats of short nucleotide (1–6 bp) sequences, are the DNA marker of choice because of their highly polymorphic, ubiquitous distribution within the genome, ease of genotyping through Polymerase chain reaction, selectively neutral, co‐dominant and multiallelic nature. Six microsatellites, three polymorphic and three monomorphic have been characterized for the first time in a bamboo species, Bambusa arundinacea belonging to the family Poaceae. The numbers of alleles per locus ranged from 2 to 13. Cross species amplification was tested in 18 other bamboo species. Monomorphic simple sequence repeats (SSRs) were found to be cross amplified in most of the species tested and polymorphic ones in only three to four species. The utility of SSR loci in a genetic diversity study of B. arundinacea and other cross‐amplified bamboo species has been discussed. This study will help in population genetic studies in bamboo species. 相似文献
88.
Development and application of functional markers in maize 总被引:8,自引:0,他引:8
Thomas Lübberstedt Imad Zein Jeppe Reitan Andersen Gerhard Wenzel Birte Krützfeldt Joachim Eder Milena Ouzunova Shi Chun 《Euphytica》2005,146(1-2):101-108
Summary Functional markers (FMs) are derived from polymorphic sites within genes causally involved in phenotypic trait variation (Andersen,
J.R. & T. Lübberstedt, 2003. Trends Plant Sci 8: 554–560). FM development requires allele sequences of functionally characterized
genes from which polymorphic, functional motifs affecting plant phenotype can be identified. In maize and other species with
low levels of linkage disequilibrium, association studies have the potential to identify sequence motifs, such as a few nucleotides
or insertions/deletions, affecting trait expression. In one of the pioneering studies, nine sequence motifs in the dwarf8 gene of maize were shown to be associated with variation for flowering time (Thornsberry, J.M., M.M. Goodman, J. Doebley,
S. Kresovich, D. Nielsen & E.S. Buckler, 2001. Nat Genet 28: 286–289). Proof of sequence motif function can be obtained by
comparing isogenic genotypes differing in single sequence motifs. At current, the most appropriate approach for this purpose
in crops is targeting induced local lesions in genomes (TILLING) (McCallum, C.M., L. Comai, E.A. Greene & S. Henikoff, 2000.
Nat Biotechnol 18: 455–457). In central Europe, maize is mainly grown as forage crop, with forage quality as major trait,
which can be determined as proportion of digestible neutral detergent fiber (DNDF). Brown midrib gene knock out mutations have been shown to be beneficial for forage quality but disadvantageous for overall agronomic performance.
Two brown midrib genes (bm1 and bm3) have been shown to be involved in monolignol biosynthesis. These two and additional lignin biosynthesis genes have been
isolated based on sequence homology. Additional candidate genes putatively affecting forage quality have been identified by
expression profiling using, e.g., isogenic bm lines. Furthermore, we identified an association between a polymorphism at the COMT locus and DNDF in a collection of European
elite inbred lines. 相似文献
89.
Abstract: Harold Brookfield's academic career spans more than half a century, traversing small tropical and subtropical islands and mountainous uplands, focusing on people–environment relations and linking to a diversity of institutions and disciplines. His unwavering commitment to fieldwork at the local level and to comparative study is paralleled by a healthy scepticism with respect to academic trends and orthodoxy of any kind, whether intellectual or physical. It is the farmers of the developing world who are the source of much of his inspiration. His theoretical contributions are based essentially on his observations of their practices and his learning from their experiences. His academic insights into the processes of change in rural areas of Melanesia, East and South‐East Asia, Africa and South America, where small‐scale ecological studies are linked to global forces, are of lasting significance. 相似文献
90.
电厂建设项目土壤加速侵蚀系数测算研究 总被引:2,自引:2,他引:2
采用实验小区法、类比法、实地调查和地面观测等多种方法对萍乡赣能电厂建设项目的厂区扩建区、施工区、施工临时用地区、厂外公路、临时堆土弃渣场和取料场等区域施工当中的土壤加速侵蚀系数进行测算,结果表明:厂区扩建区和施工临时用地区的土壤加速侵蚀系数为21,施工区的土壤加速侵蚀系数为32;厂外公路路堑边坡土壤加速侵蚀系数为35,路堤边坡土壤加速侵蚀系数为44、路面土壤加速侵蚀系数为21;取料场采挖边坡的土壤加速侵蚀系数为76,采挖台面的土壤加速侵蚀系数为64;临时堆土场、弃渣场的年均流弃比为6.4%。 相似文献