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1.
动物分子育种:一门发展中的新型学科   总被引:10,自引:0,他引:10  
动物分子育种的理论基础是分子遗传学和分子数量遗传学,操作方法依赖于DNA重组技术,同时也将结合一些经典的育种技术。分子育种的目标不仅仅是改良畜禽的重要生产性状,也将创造一些非常性经济性状。本文简要地介绍了动物分子育种的主要研究内容及其发展现状,也提出了在育种实践应用分子育种的策略与方法,这将有助于我国在动物分子育种领域内积极地进行探索。  相似文献   

2.
甘蓝型油菜(Brassica napus,AACC,2n=38)是中国种植面积最大的油料作物.单核苷酸多态性(single nucleotide polymorphism,SNP)分子标记作为最重要的分子标记技术对正向遗传学研究有极其重要的作用.过去五年,白菜(Brassica rapa)、甘蓝(Brassica oleracea)以及甘蓝型油菜的基因组序列的组装完成,更增大了SNP分子标记在油菜中的研究潜力.本文分析了SNP的生物性质及其技术研究,回顾SNP在甘蓝型油菜中的应用现状,重点关注SNP在连锁图谱构建以及关联分析中的应用,同时,综述了SNP在甘蓝型油菜种质资源分析、群体进化分析,以及分子标记辅助育种等方面的众多应用,旨在为理解和研究SNP分子标记在甘蓝型油菜中的应用提供参考.  相似文献   

3.
为了利用生物学技术和手段来解决农业问题,让基因组测序技术、转基因及基因编辑等现代分子生物学技术为农业遗传育种服务,实现常规育种与分子设计育种的紧密结合,加速作物精准育种进程,近年颇受学术界关注。现梳理了一些分子生物学专用名词概念,概述了目前在正向遗传学研究中如何利用极端表型材料基于全基因组测序的BSA-Seq方法(MutMap法、MutMap+法、MutMap-Gap法、QTL-seq法)快速定位重要农艺性状的QTL/基因,为快速定位和克隆候选基因提供新思路。  相似文献   

4.
DNA双螺旋结构的发现和重组DNA技术、PCR技术的产生极大的促进了分子遗传学的发展。几十年来,DNA一直被认为是决定生命遗传信息的主要物质。但是,大量的事实表明,生命遗传信息从来就不是基因所能完全决定的。例如,同卵双生的双胞胎具有完全相同的基因组,在相同的环境下长大后,他们在性格、健康等方面都会有较大的差异,这并不符合经典遗传学理论预期的情况,让人产生疑问;  相似文献   

5.
分子标记辅助选择(Marker-assisted-selection;MAS)是作物遗传改良的有效工具。随着高通量低成本SNP标记的开发应用和生物信息学的快速发展,MAS的应用拓展到了全基因组选择(Genomic Selection,GS),大大地提高了选择的效率和精准性。因技术和费用的限制,MAS未能广泛应用。为拓展MAS在作物育种中的应用路径,并发挥其最大潜力。通过查阅相关文献,综述了MAS在作物育种中的优势及其应用途径;分析了MAS应用受限的原因所在,并针对具体问题提出了对策;预测了MAS的应用前景:因高通量基因分型及基因组测序技术等的快速发展,未来MAS费用肯定显著降低,选择效率将大幅提升,致使MAS的应用空间更为广阔。  相似文献   

6.
徐江  梁劬 《核农学通报》1995,16(2):89-93
遗传图谱的建立,是遗传学研究中一个很重要的领域,是对基因组进行系统性研究的基础,也是遗传育种的依据。90年代发展起了一种DNA多态性分析的新方法-RAPD技术,克服了以往RFLP和PCR技术的很多缺陷,已被广泛应用于基因组研究的各个方面。文中介绍了RAPD技术的原理,研究成果,以及未来展望。  相似文献   

7.
农业生物信息学   总被引:3,自引:0,他引:3  
20世纪80年代末,人类基因组计划(Human Genome Project,HGP)的启动推动了生物信息学的产生和蓬勃发展。人类基因组计划的直接结果是获得了大量不连续的数据。对这些数据的收集、存储、分析和解释,从中获取有用的生物学信息,导致了生物信息学的产生。生物信息学在农作物基因组分析中的深入应用产生了农业生物信息学,本文在介绍生物信息学理论和国内外研究进展的基础上,分析了生物信息学在农作物育种及农作物基因组学等方面的应用前景,提出了我国农业生物信息学的研究和开发建议。  相似文献   

8.
全基因组关联分析在作物育种研究中的应用   总被引:1,自引:0,他引:1  
曹英杰  杨剑飞  王宇 《核农学报》2019,33(8):1508-1518
全基因组关联分析(GWAS)是一种针对全基因组范围内的遗传变异进行基因分型,寻找某一群体内性状与分子标记或候选基因间关系的分析方法。GWAS对于连锁标记开发、目的基因挖掘和复杂性状的遗传研究具有重要作用,在作物数量性状研究和作物育种中得到了广泛的应用。本文简要综述了利用GWAS挖掘与作物重要性状关联基因的研究过程中,群体结构、群体数量、连锁不平衡(LD)等因素对GWAS的影响,并重点分析了GWAS在粮食作物育种研究中取得的最新进展,初步讨论了GWAS对作物遗传育种的意义、存在的问题和未来发展趋势等,为利用GWAS在作物育种方面的运用,促进作物分子标记辅助育种以及提高育种效率提供了一定的理论依据。  相似文献   

9.
远缘杂交是观赏植物种质创新和品种改良的重要方法,但远缘杂交易出现假杂种,对远缘杂交后代进行杂种真实性鉴定、筛选出目的杂种在观赏植物远缘杂交育种中具有重要作用。本文简要介绍了观赏植物远缘杂交后代中假杂种的可能产生途径,详细阐述了形态特征、细胞遗传学、分子细胞遗传学、分子标记、生理生化指标等主要方法在观赏植物远缘杂种鉴定上的研究进展,重点总结了FISH、GISH等原位杂交技术和RAPD、AFLP、SSR等分子标记鉴定方法的应用情况;并提出观赏植物远缘杂交育种中杂种真实性鉴定方法的选择策略,对未来的发展方向进行展望,以期为相关研究提供参考。  相似文献   

10.
全基因组测序(whole genome sequencing,WGS)是指通过高通量测序技术对物种个体或群体的基因组进行测序,并通过生物信息学技术对序列特征进行分析,以在全基因组水平探究物种的进化规律和筛选功能基因,主要包括从头测序(de novo)和重测序(re-sequencing).WGS具有信息全面、精确、高效等优点,尤其能对未知基因和未知结构变异进行高效探索,随着高通量测序技术的发展,WGS成本快速降低,使其迅速超越传统策略,成为当前群体进化分析和功能基因挖掘的最主要研究策略,并在畜禽中得到广泛应用.目前已经对鸡(Gallus gallus)、猪(Sus scrofa)、牛(Bos taurus)、绵羊(Ovis aries)、山羊(Caprahircus)、马(Equus caballus)、鸭(Anas platyrhynchos)和狗(Canis lupus)等畜禽进行了大量WGS研究,探究了畜禽进化规律,并挖掘出许多关键功能基因.此外,WGS在未来畜禽泛基因组的构建和全基因组选择育种中也将有广泛的应用.本文主要对WGS的特征和发展进行了介绍,概述和讨论了其在畜禽群体进化和功能基因挖掘中的应用,并简述了其关键要点和应用前景,以期为WGS在畜禽中得到进一步的应用提供理论参考.  相似文献   

11.
低氮和干旱胁迫对富士和秦冠生长及氮素利用的影响   总被引:2,自引:2,他引:0  
【目的】以富士(Fuji)、 秦冠(Qinguan)嫁接在平邑甜茶(Malus hupehensis Rehd.)上的当年生盆栽苗为试验材料,采用砂培方法,研究了缺氮胁迫和干旱对富士和秦冠生长情况、 光合参数、 植株各部位氮磷钾含量及氮素利用效率的影响,分析比较了低氮干旱条件下富士和秦冠生长及氮素利用的差异,以期为果树生产高效肥水利用提供理论指导。【方法】试验共设四个处理: 正常氮正常水(ZZ)、 低氮正常水(DZ)、 正常氮干旱(ZG)、 低氮干旱(DG)。氮素和水分均设置两个水平,分别为正常氮(6 mmol/L NO-3-N)、 低氮(0.3 mmol/LNO-3-N)、 正常供水(保持盆中砂子相对含水量为饱和含水量的80%~85%)、 干旱处理(保持盆中砂子相对含水量为饱和含水量的60%~65%)。【结果】富士和秦冠的生物量(茎和叶)、 株高茎粗等生长指标以及光合速率、 气孔导度、 蒸腾速率均为正常氮正常水(ZZ)>低氮正常水(DZ)>正常氮干旱(ZG)>低氮干旱(DG),并且相对应处理下秦冠的以上指标均高于富士;正常供水下,缺氮处理使富士、 秦冠的根冠比比正常氮处理均有所增加,富士提高了2.05%,秦冠提高了22.40%。富士和秦冠的氮、 磷、 钾含量均表现出正常氮正常水(ZZ)>低氮正常水(DZ)>正常氮干旱(ZG)>低氮干旱(DG); 氮、 钾元素含量在植株各部位的分布顺序依次是叶>根>茎,磷元素则是根>叶>茎;光合氮素利用效率(PNUE)和氮素利用效率表现为秦冠处理之间差异极显著,富士处理之间差异不显著;秦冠的PNUE和NUE明显高于富士,在低氮正常水(DZ)处理下,秦冠氮肥利用率比富士高42.07%,在低氮干旱(DG)处理下高64.14%;低氮胁迫下富士和秦冠的NUE显著提高,并且秦冠提高的幅度高于富士。【结论】施用氮肥能够显著提高富士与秦冠的干物质量,同等水肥条件下,秦冠生长优于富士;水分亏缺会减少叶片对氮的吸收,干旱条件下适度增施氮肥,可提高果树的抗旱能力;低氮干旱胁迫下秦冠的生长指标、 光合指标及氮素利用效率指标均优于富士,表现出较强的抗低氮干旱胁迫的能力。  相似文献   

12.
Laser-induced breakdown spectroscopy (LIBS) is a new technique for the analysis of plant material. This study investigates the application of LIBS to pasture-based plant samples. The LIBS measurements were obtained from pelletized pasture samples (100 samples) that had been also analyzed by inductively coupled plasma–optical emission spectroscopy (ICP-OES) following microwave digestion for calibration and comparison purposes. Comparisons for elements sodium (Na), potassium (K), magnesium (Mg), calcium (Ca), manganese (Mn), iron (Fe), copper (Cu), zinc (Zn), boron (B), phosphorus (P), and sulfur (S) showed that LIBS could be used for almost all the standard profile total elements with concentrations down to low mg/kg levels (observed error of Na: 0.024 percent, K: 0.18 percent, Mg: 0.016 percent, Ca: 0.073 percent, P: 0.017 percent, Mn: 31 mg/kg, Fe: 150 mg/kg, Zn: 6.6 mg/kg, and B: 1.1 mg/kg). Elemental analysis at less than mg/kg levels was not possible using LIBS. The elements S and Cu were particularly difficult to analyze with reliability using LIBS at the concentration levels found in the plant samples. Replacing microwave digestion and subsequent ICP analysis with a direct analysis of dried plant samples using LIBS has the potential to improve the productivity and reduce the cost of testing.  相似文献   

13.
“Wicked” problems are those that are complex and that change when solutions are applied. Many conflicts in conservation fall into this category. The study approached the problem of how to constrain the apparent wickedness of a problem in the conservation management of a species by using simple empirical indicators to carry out iterative assessment of the risk to a population and to document how this risk evolves in relation to the addition of new data and the implementation of management actions. Effects of high levels of uncertainty within data and also concerning population structure were examined through stochastic simulation and by exploration of scenarios. Historical trends in the example used, the Steller sea lion, showed rapid declines in abundance in some regions during the 1980s. The current total population is 130,000-150,000 Steller sea lions through Alaska and British Columbia and this number has been stable since about 1990 in spite of regional differences in population dynamics. Regional differences in the sequence of changes in the number of pups and non-pups, suggested that an internal re-distribution of juveniles could have happened between 1980 and 1990. Current productivity also appears close to the long-term mean. Stochastic population projection using various scenarios showed that, based upon this history, the risk of extinction for the population has declined and is below reasonable thresholds for considering the population to be endangered. The trends in risk suggest that management actions taken since 1990 have probably been effective. Consequently, the conservation management objectives for the Steller sea lion are probably being met. The approach provides a mechanism, based upon experience and scenario analysis, for exploring future policy options and may help to constrain the debate amongst stakeholders about the cost-benefit trade-offs associated with different options.  相似文献   

14.
Nutrient distributions under no tillage (NT) compared with conventional disk-and-bed tillage (CT) management in the warm, humid region of the southeastern USA need to be assessed so that future placement, quantity, and type of fertilizers can be altered, if necessary, to efficiently match crop demands. We determined soil-profile distributions of pH, N, P, S, K, Ca, Mg, Na, Zn, Fe, Mn, and Cu to a depth of 0.9 m at the end of 8.5 years of continuous CT and NT management on a Weswood silty clay loam (fine, mixed, thermic Fluventic Ustochrept) in southcentral Texas. Most dramatic changes occurred within the 0–0.05 m depth, where soil under NT had lower pH, Fe, and Cu than under CT, but greater P, K, Zn, and Mn. Greater P and K under NT than under CT also occurred below the till-zone (0.15–0.3 m). At a depth of 0–0.3 m, soil under NT contained greater amounts of extractable P, K, Zn, Fe, Mn, and Cu than under CT. Nitrogen fertilization had little effect on nutrient distributions, except resulting in greater extractable K at 0–0.05 m and greater nitrate at 0–0.15 m. Few changes in soil-profile distributions were observed for extractable S, Ca, Mg, and Na. Long-term continuous use of NT on this fine-textured, high-fertility (except for N) soil had no apparent adverse effects on nutrient distributions relative to CT, but enhanced conservation and availability of P, K, Zn, Fe, Mn, and Cu near the soil surface where crop roots proliferate.  相似文献   

15.
正The Center for Agricultural Resources Research(CARR),the Institute of Genetics and Developmental Biology(IGDB),Chinese Academy of Sciences,invites applicants for several research group leader positions.CARR is one of the research organizations in Chinese Academy of Sciences(CAS).We seek nominations and applications from individuals who have expertise and a record of accomplishment in research areas related to ecology,agro-hydrology,  相似文献   

16.
The responses of tallgrass prairie plant communities and ecosystem processes to fire and grazing are well characterized. However, responses of invertebrate consumer groups, and particularly soil-dwelling organisms, to these disturbances are not well known. At Konza Prairie Biological Station, we sampled soil macroinvertebrates in 1994 and 1999 as part of a long-term experiment designed to examine the effects and interactions of annual fire, mowing, and fertilization (N and P) on prairie soil communities and processes. For nearly all taxa, in both years, responses were characterized by significant treatment interactions, but some general patterns were evident. Introduced European earthworms (Aporrectodea spp. and Octolasion spp.) were most abundant in plots where fire was excluded, and the proportion of the total earthworm community consisting of introduced earthworms was greater in unburned, unmowed, and fertilized plots. Nymphs of two Cicada genera were collected (Cicadetta spp. and Tibicen spp.). Cicadetta nymphs were more abundant in burned plots, but mowing reduced their abundance. Tibicen nymphs were collected almost exclusively from unburned plots. Treatment effects on herbivorous beetle larvae (Scarabaeidae, Elateridae, and Curculionidae) were variable, but nutrient additions (N or P) usually resulted in greater densities, whereas mowing usually resulted in lower densities. Our results suggest that departures from historical disturbance regimes (i.e. frequent fire and grazing) may render soils more susceptible to increased numbers of European earthworms, and that interactions between fire, aboveground biomass removal, and vegetation responses affect the structure and composition of invertebrate communities in tallgrass prairie soils.  相似文献   

17.
Abstract

A 3-year study was carried out to investigate quality parameters in 14 tree fruit and berry species grown in southern Norway. The species were blueberry, apple, aronia, sour cherry, sweet cherry, red raspberry, strawberry, blackcurrant, gooseberry, red currant and elderberry, harvested along with wild bilberry, cloudberry and lingonberry. Significant differences between species were identified for all quality parameters. The coefficient of variation between species was lowest for pH (12.5%), dry matter (18.9%) and soluble solids (25.3%), followed by titratable acids (59.3%), total phenolics (83.8%), antioxidant capacity FRAP (85.7%) and antiradical power by the DPPH-assay (97.8%), total monomeric anthocyanins (132%) and ascorbic acid (137%). Average coefficient of variation within species were lower and ranged from 4 (pH) to 62% (ascorbic acid). Only the FRAP values were significantly affected by harvesting year with lower levels in 2004 than in 2005 and 2006. There were significant interactions between species and harvesting year for dry matter, soluble solids, pH, ascorbic acid and FRAP. The results indicate generic ranges in composition within species independent upon growing location and climate, and the composition of the tree fruits and berries is not likely to deviate from these ranges. It is concluded that desirable composition of tree fruits and berries and their products should primarily be achieved by selection among species rather than searching fors broadened variation within individual species.  相似文献   

18.
To evaluate the feasibility of long-term desert reforestation technology of mixed vegetation, cardon cactus (Pachycereus pringlei) seedlings from indoor and outdoor nurseries were planted in the field adjacent to one seedling of potential legume nurse trees: mesquite amargo (Prosopis articulata), yellow palo verde (Parkinsonia microphylla), and blue palo verde (Parkinsonia florida). Some of the planting holes were also supplemented with common dairy compost. Additionally, the combinations of legume tree–cactus were inoculated with either a consortium of desert arbuscular mycorrhizal (AM) fungi, plant growth promoting bacteria (PGPB; the diazotroph Azospirillum brasilense Cd, and the phosphate solubilizer Paenibacillus sp.), or a mixture of all. The field experiments were evaluated periodically during 30 months for survival and growth. Cardons reared in an outdoor screen house survived better in the field than those reared in a controlled growth chamber and hardened later outdoors. Association with any legume nurse tree increased survival and enhanced growth of untreated cardons. For cardons growing alone, application of either compost, AM fungi, and all the treatments combined increased survival. For these plants, no treatment affected plant growth during the first 3 months after transplanting. Later, all treatments, except for AM fungi, enhanced plant growth. However, only 2 years after transplanting the enhanced growth effect of AM fungi was also significant. In the presence of the legume nurse trees, transient positive effects on cardon growth were recorded. General evaluation after 30 months of cultivation showed that the treatments positively affected cardon growth when growing alone or in combination only with mesquite amargo but not with the other two legume trees. This study proposes that young legume trees have the capacity to enhance survival and growth of cardon cactus, depending on the legume cactus combination. Additional treatments such as compost or PGPB can either amplify the effect or else attenuate it.  相似文献   

19.
Detailed karyotypes and 4C DNA amounts have been studied in five cultivars of Cajanus cajan and 20 species belonging to Cajanus, Rhynchosia, Dunbaria, Flemingia and Paracalyx. C. cajan shows intraspecific variability and its karyotype is most similar to that of C. cajanifolius (sect. Cajanus) in the morphology and number of satellite chromosomes and the lack of any correlation between chromosome size within the complement and asymmetry. Karyotypes of C. lineatus and C. sericeus belonging to sect. Atylia are similar with respect to maximum r-index and the ratio of longest and shortest chromosomes in their respective complements. C. acutifolius (sect. Frutocosa) is distinct in having a very low ratio (1.44) between the longest and the shortest chromosomes, while in C. albicans, C. goensis, C. scarabaeoides (sect. Cantharospermum) there is no chromosome pair with r-index >2.0. C. mollis and C. volubilis (sect. Volubilis) show similarity with regard to ratio between the longest and the shortest chromosomes and a distinct chromosome pair with an arm ratio of 2.7 and C. platycarpus is distinct (sect. Rhynchosoides) in having the smallest ratio (1.36) between the longest and the shortest chromosomes. 4C DNA amounts in Cajanus and Rhynchosia vary between 3.28 pg to 11.69 pg and 4.92 pg to 11.13 pg respectively, while in Dunbaria, Flemingia and Paracalyx these vary between 4.70 and 7:06 pg. In the genus Cajanus karyotypic features and 4C DNA amounts agree with the sectional classification and bring out a close relationship between C. cajan and C. cajanifolius. This is supported by studies based on seed protein patterns, isozyme analysis, trypsin and chymotrypsin inhibitor patterns, RFLP and RAPD data and crossability relationships. A clear relation between DNA amount and abnormalities effecting the extent of pairing and recombination in interspecific hybrids shows the importance of this study in developing future breeding programme involving C. cajan and its wild relatives that are of potential value.  相似文献   

20.
Potassium (K) fixation and release in soil are important factors in the long-term sustainability of a cropping system. Changes in K concentration and characteristics of K fixation and release in rhizosphere and nonrhizosphere soils in the rapeseed (Brassica napus L.)–rice (Oryza sativa L.) rotation were investigated using a rhizobox system. The concentrations of different forms of K in both rhizosphere and nonrhizosphere soils decreased with plants compared to without plants, regardless of K fertilizer application. Potassium uptake by crops mainly came from the rhizosphere soil. In the treatment without K fertilizer (–K), the main form of K supplied by the soil to the crops was 1.0 mol L?1 nitric acid (HNO3) nonextractable K, followed by nonexchangeable K, and then exchangeable K. In the treatment with K fertilizer (+K), the main K forms supplied by the soil to the crops were exchangeable K and nonexchangeable K. The amount and rate of K fixation after one cycle of the rapeseed–rice rotation was greater in rhizosphere soil than in nonrhizosphere soil. The amount and rate of K fixation of soil in the +K treatment were significantly less than in the –K treatment. The cumulative amounts of K released with 1.0 mol L?1 ammonium acetate (NH4OAc) and 1.0 mol L?1 HNO3 extraction increased with the increasing numbers of extractions, but the K-releasing power of soil by successive extraction decreased gradually and finally became almost constant. The release of K was less in rhizosphere soil than in nonrhizosphere soil. The release of K in the +K treatment was similar to that in the –K treatment in rhizosphere soil, but the K release in nonrhizosphere soil was greater with the +K than the –K treatment. Overall, the information obtained in this study will be helpful in formulating more precise K fertilizer recommendations for certain soils.  相似文献   

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