我国短季棉50年早熟性育种成效研究与评价

通过第一次收花率、生育期、营养生长期与生殖生长期比较等性状总结了我国短季棉早熟性育种的成效。对不同年代短季棉品种的基因型值分析表明,短季棉生育期缩短9~14 d,本试验不同年代品种平均缩短2.5 d。通过对早熟性多个性状的对比,分析了辽棉系列短季棉与中棉所系列短季棉的不同育种策略。     

应用RAPD对短季棉品种遗传多样性的初步评价

短季棉在我国未来棉业可持续发展中有着不可替代的作用.迄今为止,我国已育成近200多个短季棉品种,但却未对其进行系统的遗传多样性分析.本研究则利用RAPD标记对我国29份不同年代不同生态区的早熟短季棉品种进行了遗传多样性的比较分析,使育种工作者更全面地了解早熟短季棉的亲缘关系和遗传基础,并且为指导早熟短季棉育种,合理利用种质资源提供参考数据.     

中国短季棉遗传改良研究进展及发展方向

短季棉品种遗传改良是实现麦棉两熟棉区粮棉双丰收的有效途径。从早熟种质资源金字棉的引进,早熟短季棉品种中棉所10号的育成,抗枯萎病品种中棉所16、辽棉10号的选育,生化辅助育种技术育成早熟不衰品种中棉所24、27和36,转单价Bt基因抗虫棉中棉所30、中棉所42和鲁棉研19,转双价Bt＋CpTI基因抗虫棉中棉所50、中棉所58的培育,到航天诱变特早熟品种中棉所64,综述了中国短季棉品种选育的主要研究进展;提出了短季棉育种应加强抗黄萎病材料创制、克服产量和早熟性负相关和解决特早熟品种早衰等遗传改良重点;指出借助分子育种与常规育种技术相结合,培育麦后直播特早短季棉和杂交短季棉是今后短季棉遗传育种的方向。     

山东省短季棉品种的更新及推广中存在的问题

山东省地处黄河流域棉区,短季棉自20世纪70年代中期开始种植,至80年代中期得到快速发展,这与短季棉品种的更新有着密切的联系,科学地认识和了解我省短季棉品种的更新与发展及推广中存在的问题,将有利于短季棉品种得到科学而合理的应用。1短季棉品种的更新与发展山东省短季棉自20世纪70年代中期开始试种,种植品种主要是聊夏棉1号、黑山棉1号、岱字棉15号等,由于这些品种生育期偏长(120天左右),生产技术不配套,推广面积不大。1981年中棉所10号开始在我省试种,该品种生育期较聊夏棉1号、黑山棉1号提前8～10天,且丰产性较好,试种较为成功,这使我…     

我国短季棉品种的演变及发展前景

本文概述了短季棉的基本概念，分析总结了我国短季棉品种的演变，并研究展望了其发展前景。     

早熟不早衰短季棉品种(系)及其杂交后代抗氧化酶系统活性变化

在短季棉育种中,早熟性是最主要的性状,但早熟品种容易早衰,从而影响短季棉的产量和纤维品质。以早熟不早衰品种、早衰品种、F1和F2为材料,对不同基因型短季棉抗氧化酶系统的活性进行了比较研究,旨在探索棉花早熟不早衰的生理学机制及其遗传性,为早熟不早衰的短季棉品种选育提供指导。1材料和方法1.1试验材料试验材料选用短季棉品种(系)10个,其中早衰类型品种(系)5个,即中棉所10、中450407、中652585、中619和豫早28;早熟不早衰品种(系)5个,分别是辽4086、中925383、中061723、中961662和豫1201。同时,利用以上材料配成5个早熟不早衰×早衰…     

短季棉品种比较试验

短季棉是生产上实行麦(油)棉两熟制的品种类型，对于稳定粮油生产，提高棉田经济效益有 十分重要意义。对外引的短季棉新品种(系)，进行田间对比试验，进一步鉴 定其丰产性、早熟性、抗病性及适应性。为棉麦(油)两熟技术和麦棉套种技术推广对棉花品 种的选择提供科学依据。     

我国短季棉50年产量育种成效研究与评价

对198份短季棉材料的系谱分析和短季棉品种的基因型值分析表明:①20世纪90年代品种皮棉单产比50年代增产50.29%,比60年代增产51.44%,比70年代增产26.6%、比80年代增产20.8%。②在产量构成因素中以衣分和铃重提高为主要增产模式,提高枯黄萎病抗性也是重要增产因素。③育种技术从50年代系统选育到杂交、复交、多父本混交、辐射育种、空间技术育种、生物技术育种对品种提高取得了非常重要的作用,特别是采用生化遗传育种解决短季棉早熟早衰,选育早熟不早衰、青枝绿叶吐白絮的早熟、优质、多抗短季棉品种行之有效。④中棉所系列品种和辽棉系列品种育种技术路线不同,辽棉以缩短棉花前期营养生长,提高早熟性,以延长铃期,增加铃重,提高产量和纤维品质。中棉所系列至90年代发展较成熟的生化遗传育种技术,在缩短生育期的前提下,适当延长前期营养生长期,增加光合产物积累,延缓棉株早衰,增加后期光合作用;通过大幅度提高衣分,增加皮棉产量;靠缩短生殖生长期、吐絮畅而集中等提高早熟性;通过提高SOD酶等抗氧化酶系统,提高抗性和延缓衰老,达到各性状综合协调提高。     

与时俱进 选育高产优质多抗短季棉品种

论述了发展短季棉生产对缓解我国粮棉争地矛盾的意义。短季棉生态区的划分为短季棉育种提供了科学依据,根据生产实际不断调整育种目标和技术路线,培育出多个大面积推广的优良短季棉品种。提出了短季棉育种的远景规划和目标。     

黄河流域棉区麦棉两熟短季棉关键栽培技术

短季棉俗称夏播棉或早熟棉，是生长发育期相对较短的棉花种植类型。其在我国黄河流域棉区的种植面积最大，分布最广，全区常年短季棉种植面积近60万hm^2，广泛分布在河南、河北、山东、山西等省。短季棉的发展，对提高光、温和土地利用率，充分利用自然资源，缓解粮棉争地矛盾具有积极作用，极具发展前景。以短季棉为标志的粮棉两熟栽培，更是实现提高单产、增加总产，实现粮棉同步增产的必由之路。由于麦棉两熟短季棉的独特生育环境条件，形成其生育特点，须有配套的栽培技术。笔者针对黄河流域棉区持殊的气候特点，根据多年试验，提出以下关踺栽培措施。     

我国陆地棉品种的遗传多样性研究初报

选用１８个随机引物，对２１个陆地棉品种作ＲＡＰＤ分析，并对各品种的指纹图谱进行了聚类和相似性分析。结果表明大部分品种与其系谱吻合。研究结果充分展示了ＲＡＰＤ技术可以作为棉花品种分类和遗传多样性研究的可行方法。     

Radiomutants of chrysanthemum (Dendranthema grandiflora Tzvelev) of the Lady group: RAPD analysis of the genetic diversity

Random amplified polymorphic DNA (RAPD) markers were used to study the molecular characterization of 10 new radiomutants of chrysanthemum. The original cultivar ‘Richmond’ differed in genetic distance from its Lady group mutants. The analysis of genetic similarity indices revealed low diversity within the radiomutants. The dendrogram obtained after cluster analysis separated the new cultivars as a group that differed from the original cultivar ‘Richmond’. The Lady group cultivars, derived from one original cultivar by radiomutation, could be distinguished from each other by using RAPD markers of only a single primer or sets of two or three primers. Polymerase chain reaction analysis proved the efficiency of the RAPD method for DNA fingerprinting of the original cultivar ‘Richmond’ and its new radiomutants.     

Analysis of loquat germplasm (Eriobotrya japonica Lindl) by RAPD molecular markers

The loquat’s adaptation to Spain has proved very successful. In the Valencia area, the crop has met with very good environmental conditions for its development. Many new cultivars have been selected by growers and a European loquat germplasm collection has been established in Valencia at IVIA. An efficient sampling as well as implementation of germplasm resources requires the accurate identification of plant material. Molecular markers offer an effective tool for cultivar fingerprinting, estimation of genetic similarity and relationships. In this study, as a tool for germplasm management, RAPD markers were tested. Thirty-six primers were used to screen 33 cultivars. Twenty-three primers proved polymorphic. These primers generated 29 polymorphic amplification fragments that were selected as markers. Twenty-two cultivars out of 33 were identified by unique combinations of RAPD markers. Four different combinations were shared by two or more cultivars each. Cluster analysis based on the similarity matrix obtained from Nei’s coefficient among cultivars showed groupings that agreed according to geographical and genetic origin. RAPD technology was useful in distinguishing those cultivars obtained through hybridization but could not be used to distinguish those obtained by selection of mutations. This revised version was published online in August 2006 with corrections to the Cover Date.     

RAPD和AFLP标记分析中国马铃薯主要品种的遗传多样性

采用RAPD 和AFLP两种方法分析71份中国各地马铃薯主要品种,均可将其完全区分,并可对其进行分子鉴定;证明中国马铃薯主要品种遗传组成上差异小,遗传多样性差。由于标记方法的原理差异和栽培马铃薯遗传组成复杂性,用2种方法分类的结果有所差异。AFLP标记检测获得的Shannon-weaver指数和Simpson指数均高于RAPD标记检测的结果,AFLP标记检测多态性的能力远高于RAPD标记。AFLP标记平均每个引物组合检测到100.1个位点,其中54.9条为多态性位点,而RAPD标记的相应数据分别为12.5和9.8个。不同的标记方法在马铃薯遗传多样性研究中存在差异,聚类结果从分子水平反映了中国现有主要马铃薯品种遗传基础的狭窄。     

Genetic variation within and between two cultivars of red clover (Trifolium pratense L.): Comparisons of morphological,isozyme, and RAPD markers

Summary Morphological, isozyme and random amplified polymorphic DNA (RAPD) markers were used to estimate genetic variation within and between cultivars of red clover (Trifolium pratense L.), an important temperate forage legume. Two cultivars of red clover, Essi from Europe and Ottawa from Canada, were evaluated. Six monogenic morphological characters were observed for 80 plants from each of these two cultivars. All six morphological loci were polymorphic in the cultivar Essi whereas only four loci were polymorphic in the cultivar Ottawa. Forty plants from each cultivar were assayed for isozyme markers. A total of 21 enzyme-coding loci with 43 alleles was detected using twelve enzyme systems. Thirteen and nine of these loci were polymorphic in Essi and Ottawa, respectively. The mean number of alleles per locus was 1.81 in Essi and 1.67 in Ottawa. Seventeen random 10-mer primers were screened for RAPD markers. Nine primers which gave clear and consistent amplified products were used to assay 20 individuals from each cultivar. Each primer gave from 7 to 20 amplified bands with an average of 14.8 bands per primer. One hundred and eight of 116 putative loci were polymorphic in Essi and 90 of 98 loci were polymorphic in Ottawa. High within-cultivar variation was observed in both cultivars using both isozyme and RAPD markers. This high polymorphism makes these markers useful for germplasm characterization and genetic studies in red clover.     

Cultivar identification and genetic relationship among selected breeding lines and cultivars in chickpea (Cicer arietinum L.)

Twenty two RAPD and 22 ISSR markers were evaluated for their potential use in determination of genetic relationships in chickpea (Cicer arietinum L.) cultivars and breeding lines. We were able to identify six chickpea cultivars/breeding lines by cultivar-specific markers. All of the cultivars tested displayed a different phenotype generated either by the RAPD or ISSR primers. Though ISSR primers generated less markers than RAPD primers, the ISSR primers produced higher levels of polymorphism (% of polymorphic markers per primer) than RAPD primers. A high level of within cultivar homogeneity was observed in chickpea. Cultivars/breeding lines originating from a common genetic background showed closer genetic relationship. Chickpea lines with similar seed type(kabuli or desi) had a tendency to cluster together. This revised version was published online in August 2006 with corrections to the Cover Date.     

应用RAPD标记检测小豆种质资源的遗传多样性初探

检测野生型、半野生型及栽培型小豆种质资源的遗传多样性,对进一步探讨小豆的起源地、品种分化和传播途径具有极其重要的价值。本研究用RAPD标记方法对来自中国、日本、韩国、不丹、尼泊尔、越南等6国99份小豆种质资源DNA的遗传多样性进行了检测。7个引物共检测到102条带,具有多态性的谱带100条,其中7条带仅存在于单个材料     

利用RAPD、ISSR标记分析国兰种质资源遗传多样性的研究

旨在分析不同地区国兰间的亲缘关系,为国兰资源的开发及新品种的选育提供分子水平的参考依据。利用RAPD和ISSR分子标记技术,对7种国兰的21个品种资源进行遗传多样性和亲缘关系分析。结果表明：39个RAPD和ISSR引物在供试材料中共扩增出96条带型清晰的谱带,其遗传中31条为多态性条带;通过UPGMA聚类分析表明,21个国兰品种资源间遗传距离在1.91~6.60之间,其中春兰资源的遗传距离在1.91~4.38之间,建兰资源的遗传距离在2.60~6.20之间,寒兰资源的遗传距离在2.20~5.80之间,墨兰资源的遗传距离在3.52~6.60之间,表现出了较高的遗传多样性。聚类分析结果与传统的形态学分类结果基本一致,也说明分子标记可以在分子水平反映遗传资源的遗传多样性,具有灵敏度高、结果真实可靠等优点。本研究结果显示国兰品种间的亲缘关系与地理位置分布相关,为兰属植物的分类及遗传多样性研究提供了一定的理论支撑。     

Genetic variability of forage grass cultivars: A comparison of Festuca pratensis Huds., Lolium perenne L., and Dactylis glomerata L.

Three widely used cultivars of each of the species Festuca pratensis Huds., Lolium perenne L., and Dactylis glomerata L. were investigated by means of randomly amplified polymorphic DNA (RAPD) markers and vegetative growth traits in order to investigate genetic variability within each cultivar and to compare the level of diversity among cultivars and species. RAPD markers allowed a clear separation of the three species. Genetic variability based on RAPD markers was considerably lower for F. pratensis cultivars than for L. perenne and D. glomerata cultivars which showed similar levels of variability. The proportion of variability due to variation within cultivars, determined by an analysis of molecular variance, was lower in F. pratensis (64.6%) than in L. perenne (82.4%) and D. glomerata (85.1%). A comparison of F. pratensis and L. perenne, based on vegetative growth traits, confirmed the differences in genetic variability within cultivars. F. pratensis showed lower coefficients of genetic variation for eight of ten traits when compared to L. perenne. This study demonstrates considerable differences in genetic variability which may have consequences for the adaptability and persistency of individual cultivars. This revised version was published online in July 2006 with corrections to the Cover Date.