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121.
122.
农村人力资源开发在建设社会主义新农村中起着战略性、基础性和决定性的作用。笔者结合建设新农村的具体要求,通过分析农村人力资源开发现状中存在的问题,指出了在建设新农村时期开发农村人力资源,必须要处理好自然资源开发与人力资源开发的关系,要加强农村保障体制和组织化程度建设,要重视农村教育的战略地位、农村劳动力技能培训的主导地位、建设学习型社会的根本地位,这样才能培育新农民,全面提高农民素质,为建设社会主义新农村提供人力支持和智力保障。 相似文献
123.
早籼稻品种更替过程中农艺性状的演变特征 总被引:9,自引:0,他引:9
以南方稻区品种更替过程中大面积推广的18个早籼稻代表品种为材料,按高秆品种、矮秆品种、矮抗品种、优超品种4个演变阶段,采用常规栽培方法研究其农艺性状的演变特征。结果表明,随着品种的演变,产量、收获指数、每穗粒数均有提高;有效穗、结实率、千粒重变化不大。进一步分析表明,每穗粒数的增加是着粒密度改良所致。农艺性状与年代的回归分析表明,生物量与株高在1980年后有增加的趋势,生育期有缩短的趋势。相关分析表明,决定早籼稻产量的农艺性状为生物量、株高、收获指数和每穗粒数。 相似文献
124.
Summary The genomic DNAs of 42 Pisum sativum genotypes, representing four wild and cultivated subspecies were used as templates in RAPD reactions. Amplification with eight decamer primers generated 149 polymorphic products. Genetic similarities of RAPD profiles were estimated via a coefficient of Jaccard and then the data were processed by cluster analysis (UPGMA). Each genotype was clearly identified and separated from the others. Our results show that RAPD technology is a rapid, precise and sensitive technique for identification of pea genotypes. However, the phylogenetic relationships within the Pisum sativum, which we tested by bootstrap analysis (Wagner parsimony), must be interpreted with caution. 相似文献
125.
Lemon (Citrus limon (L.) Burm. f.) is one of the most important Citrus fruit for Turkey because of its great amount of production and export. It has been cultivated for a long time in Turkey, and therefore variations for agronomical traits are likely among cultivated lemons due to bud mutations and, hybridizations. The objectives of this study were to determine variations for some selected agronomical traits and genetic markers among 12 new lemons derived from selections. Tree growth, yield, fruit quality, and molecular diversification of these clones were determined. After four years of evaluation, ‘Kutdiken’ M-51 indicated the highest canopy volume. For yield per tree, the best clone was ‘Kutdiken’ M-51. After five years of evaluation, ‘Kibris’ M-54 had the highest fruit weight and acidity. ‘Italian Memeli’ M-56 contained the lowest seed number and the highest total soluble solids. Molecular analysis, as assessed with 22 random amplification of polymorphic DNA (RAPD) and 11 inter simple sequence repeats (ISSR) primers, indicated that seven of twelve clones were separated with RAPD markers, whereas four were distinguished with ISSR markers. Combined analysis of RAPD and ISSR data detected that similarity values among the lemons clones were between 0.97 and 1.00. It can be concluded that variations in orchards are abundant and mainly due to mutations. 相似文献
126.
Bermudagrass (Cynodon ssp.) germplasm is genetically diverse and widely distributed in the world. The study was conducted to identify and assess the molecular variation and relationship among 24 cultivars developed in China, Australia and the USA. Sequence-Related Amplified Polymorphism (SRAP) was applied to cultivars identification in this study for the first time. Thirty of the 90 SRAP primer combinations generated a total of 274 clearly bands encompassing 249 (91%) polymorphic. Each bermudagrass cultivar has its unique binary code and can be distinguished from the others. Three distinct clusters were obtained by unweighted pair-group method with arithmetic averages based on the polymorphic markers. Coefficients of genetic distance among the genotypes ranged from 0.57 to 0.97. The results demonstrated that SRAP marker is a stable molecular marker technique for the identification of bermudagrass cultivars and their genetic relationships. 相似文献
127.
This work reports the transferability and polymorphism of previously reported SSRs in 10 Prunus species. The availability of a large number of SSRs in the genus Prunus makes marker choice random, while preventing comparison of results in fingerprinting studies. The availability of SSR markers, polymorphic in a wide sample of Prunus species, would facilitate marker choice, while allowing the comparison of results. In this work, microsatellite markers useful for analyzing 10 different Prunus species (P. persica, P. dulcis, P. armeniaca, P. domestica, P. insititia, P. salicina, P. cerasifera, P. avium, P. cersus and P. mahaleb) were searched through screening SSRs previously reported to be conserved and/or polymorphic in more than one Prunus species. A selected group of 13 SSRs, transferable to the 10 species, was analyzed in terms of their usefulness for analyzing these species. The amplification range, polymorphism and variability detected by these loci are reported. The information provided will be useful for Prunus genetic studies as well as conservation and management of Prunus germplasm resources. 相似文献
128.
129.
生物信息学以及植物新基因的发现研究 总被引:2,自引:0,他引:2
新基因的发现对植物生命科学的研究及发展起着不可估量的作用,可以增强植物抗逆性、提高作物产量、改善经济植物品质等.然而,在发现植物新基因的方法中,生物信息学始终扮演着重要的角色. 相似文献
130.
不同木豆品种的生物学和品质特性比较研究 总被引:2,自引:0,他引:2
以广西地方木豆品种为对照,与引进的其他7个木豆新品种进行田间比较试验,评价引进木豆品种的种性和生态适应性.结果表明:不同木豆品种的根、茎、叶、花、荚、籽粒、株型等形态特征,萌芽、生长、开花、生长期、抗病虫性等生长特性以及茎、叶、籽粒的粗蛋白、粗脂肪、粗淀粉含量都有显著差异.根据不同品种的表现:广西品种、非洲品种、缅甸品种、ICPL87119比较适应喀斯特石山区荒地、山地种植,可作为饲料、水土保持、生态保护、薪炭林等用途,ICPH8、IC-PL87091可作蔬菜和粮食用,其中ICPL87091是一个比较有希望的品种. 相似文献