Comparing mating designs to restore seed production of interspecific hybrids between Trifolium repens (white clover) and Trifolium uniflorum          下载免费PDF全文

Muhammad Naeem  Isabelle Marjorie Verry  Peter D. Kemp  James P. Millner  Warren Mervyn Williams 《Plant Breeding》2017,136(3):420-426

Interspecific hybrids between Trifolium uniflorum and cultivated white clover (Trifolium repens) have highly useful characteristics for temperate pastoral systems derived from both parent species. However, the early hybrids (F₁ and BC₁) also have unacceptably poor seed production for commerce. This study analysed the basis for the poor seed production and investigated breeding strategies for overcoming the problem. The BC₁F₁ generation produced lower‐than‐expected numbers of heads per plant and seeds per floret. Backcrossing of selected hybrids to white clover corrected these deficiencies and created new variation. Seed numbers were also returned to near target levels by recurrent selection within the BC₁ generation. Thus, it was possible to retain a theoretical average of 25% of T. uniflorum genome and still achieve high seed production per plant. The BC₁F₂ and BC₂F₁ generations produced high seed numbers per plant, along with reasonable variation. Both of these second‐generation hybrid forms have high reproductive potential and should be the focus for the selection of the desired combinations of agronomic and seed production traits.  相似文献   

斑茅F1杂交可育亲本选择及其回交后代鉴定和主要经济性状   总被引：5，自引：0，他引：5  

邓海华  符成  李奇伟  廖兆周  陈西文  梁计南  张垂明  谭中文 《热带作物学报》2004,25(4):97-101

选用8个Badila(甘蔗热带种)与斑茅属间杂交F1品系与9个甘蔗栽培品种配制了24个回交组合，其中6个F1品系的13个组合杂交可育，共获346株BC1实生苗．经同工酶分析，其中320个株系具有斑茅的特征酶带，为斑茅的真实后代。在杂交可育性和BC1后代主要经济性状方面，斑茅F1品系间和杂交组合问均存在显著差异。斑茅BC1后代的产量性状和糖分仍与甘蔗栽培品种有较大差距，但各性状的最大值已与栽培品种的相当。初步研究结果表明，YC96—40和YC95—41是较好的斑茅F1亲本材料。  相似文献   

Dissecting Genetic Basis of Deep Rooting in Dongxiang Wild Rice     

Nie Yuanyuan  Xia Hui  Ma Xiaosong  Lou Qiaojun  Liu Yi  Zhang Anling  Cheng Liang  Yan Longan  Luo Lijun 《水稻科学》2022,29(3):277-287

Deep rooting is an important trait in rice drought resistance. Genetic resources of deep-rooting varieties are valuable in breeding of water-saving and drought-resistant rice. In the present study, 234 BC₂F₇ backcross introgression lines were derived from a cross of Dongye 80 (an accession of Dongxiang wild rice as the donor parent) and R974 (an indica restorer line as the recurrent parent). A genetic linkage map containing 1 977 bin markers was constructed by ddRADSeq for QTL analysis. Thirty-one QTLs for four root traits (the number of deep roots, the number of shallow roots, the total number of deep roots and the ratio of deep roots) were assessed on six rice chromosomes in two environments (2020 Shanghai and 2021 Hainan). Two of the QTLs, qDR5.1 and qTR5.2, were located on chromosome 5 in a 70-kb interval. They were detected in both environments. qDR5.1 explained 13.35% of the phenotypic variance in 2020 Shanghai and 12.01% of the phenotypic variance in 2021 Hainan. qTR5.2 accounted for 10.88% and 10.93% of the phenotypic variance, respectively. One QTL (qRDR2.2) for the ratio of deep roots was detected on chromosome 2 in a 210-kb interval and accounted for 6.72% of the phenotypic variance in 2020. The positive effects of these three QTLs were all from Dongxiang wild rice. Furthermore, nine and four putative candidate genes were identified in qRDR2.2 and qDR5.1/qTR5.2, respectively. These findings added to our knowledge of the genetic control of root traits in rice. In addition, this study will facilitate the future isolation of candidate genes of the deep-rooting trait and the utilization of Dongxiang wild rice in the improvement of rice drought resistance.  相似文献   

白色力克斯兔、哈尔滨白兔及杂交后代血液蛋白多态性研究Ⅱ.用血液蛋白多态性剖析亲本品种与杂种后代的遗传关系     

庞有志  祖国庸  刘健  侯万文  孙金海 《中国兽医学报》1993,(1)

根据所测定的白色力克斯兔(WR)、哈尔滨白兔(HW)及杂种一代(F_1,?WR×?HW)和回交一代[B_1,?WRX×?F_1,包括分离出的力克斯毛型(B_1R)和正常毛型(B_1N)]的5个血液蛋白多态系统——红细胞酯酶(Es—1、Es—2和Es—3)、前转铁蛋白(Prt)和后白蛋白(Po)的基因频率和基因型新率,比较了群体间的基因分布,估算了各群体内的平均杂合度和群体间的遗传距离,并运用类平均聚类法进行了聚类分析.结果表明,白色力克斯兔和哈尔滨白兔基因分布差异最大.亲缘关系最远;杂种一代和回交一代基因分布差异最小,亲缘关系最近;杂交一代和回交一代与白色力克斯兔亲缘关系较近,与哈尔滨白兔较远;回交一代中B_1N和B_1R间基因分布也存在一定差异.各群体平均杂合度大小为0.5223(HW)、0.4182[B_1,0.4846(B_1N)和0.3223(B_R)]、0.1105(F_1)和0.3946(WR).研究结果表明,利用蛋白多态性探讨家兔品种或品系间亲缘关系以及区分家兔品种或品系是可行的.此外,本文还结合各群体的变异性,对白色力克斯免和哈尔滨白兔的选育进行了探讨.  相似文献   

Introduction of aromatic fragrance into cultivated tomato from the peruvianum complex'     

H. M. Kamal    T. Takashina    H. Egashira    H. Satoh  S. Imanishi 《Plant Breeding》2001,120(2):179-181

This study was performed to introduce the distinct aromatic fragrance of Lycopersicon peruvianum LA 1554 into the cultivated tomato, Lycopersicon esculentum. The strong breeding barriers existing between these two distantly related species were circumvented by the ovule selection and culture method. A large BC₁F₁ population was developed and among 127 plants, 36 were self‐compatible and yielded fruits. Fruits of some of these selected plants were found to be enriched with a sweet aromatic flavour. Sensory evaluation of the fruit aroma of these selected plants was performed by a panel of 12 members against one of the best consumer‐rated Japanese commercial tomato cultivars, ‘Momotaro’. Although extensive variation was observed in fruit‐aroma in the BC₁F₁ population, panel opinion on ‘flavour‐desirability’ significantly favoured the BC₁F₁ fruits of some selected plants over the cv. ‘Momotaro’. Therefore, it can be concluded that the aromatic fragrance of a ‘L. peruvianum’ accession has successfully been introduced into the cultivated tomato gene pool.  相似文献   

The degree of phenotypic resemblance of the near-isogenic lines of the wheat cultivar thatcher with their recurrent parent     

A. C. Zeven  J. Waninge 《Euphytica》1986,35(3):665-676

Summary Thatcher, 16 of its near-isogenic lines (NIL) and 8 donors were investigated for the degree in which the NILs phenotypically resembled their recurrent parent. In general the NILs have a good phenotypic resemblance. In a few NILs characters occur that are not seen in Thatcher. In some cases these are found in the donor indicating the presence of donor genes other than the marker gene in the NIL. In other cases a character possessed by a NIL is not present in Thatcher or in its donor. In such cases either inhibitor genes may play a part, or the donor accession that accompanies the set of NILs may not be the donor used to breed the NIL. Two causes are possible. One is that the donor was a mixture of genotypes, the other is contamination.The presence of donor genes other than the marker Lr gene(s) in a NIL may lead to unexpected results or, what is worse, to wrong conclusions.  相似文献   

Production and characterization of Raphanus sativus-Brassica rapa monosomic chromosome addition lines     

Y. Kaneko    H. Yano    S. W. Bang  Y. Matsuzawa 《Plant Breeding》2001,120(2):163-168

Breeding of Raphanus sativus‐Brassica rapa monosomic chromosome addition lines (MALs, 2n = 19) was carried out by backcrossing the synthesized amphidiploid line, Raphanobrassica (R. sativus×B. rapa, 2n = 38, RRAA, line RA89) with R. sativus cv. ‘Shogoin’ (2n = 18, RR). In the first cross of Raphanobrassica× radish, four sesquidiploidal BC₁ plants (2n = 28, RRA, RA89‐36‐1, RA89‐31‐1, RA89‐31‐2, RA89‐31‐3) were successfully developed. In these plants, the chromosome configurations of 9II + 10I and 10II + 8I were observed frequently at first metaphase (MI) of meiosis in pollen mother cells (PMCs). The RA 89‐36‐1 plant produced many seeds in the reciprocal backcrosses with radish. About 50% of the BC₂ plants obtained from the cross of RA89‐36‐1 plant × radish were 2n = 19 plants, followed by 2n = 18 plants (24%) and 2n = 20 plants (19%). In the reciprocal cross, 2n = 19 plants were also developed at the rate of 40%. From analysis of specific morphological traits, 2n = 19 plants were classified into eight types (a‐h). When 25 selected primers were used in polyacrylamide gel electrophoresis, random amplified polymorphic DNA (RAPD) markers derived from B. rapa for each type of MAL were detected in numbers between three for e‐type and 16 for b‐type. RAPD markers specific for each type alone were from one (OPE 05‐344) for h‐type to nine for b‐type. In the g‐type, no marker specific to this type alone was observed. However, 19 bands were common between at least two types. These MAL plants exhibited predominantly the chromosome configuration of 9II + 1I at MI of PMCs, pollen and seed fertility being the same level as the radish cv. ‘Shogoin’. From the morphological traits and DNA markers, eight different MAL types among 10 expected were identified.  相似文献   

Quantitative trait loci (QTL) affecting sugars, organic acids and other biochemical properties possibly contributing to flavor, identified in four advanced backcross populations of tomato     

T.M. Fulton  P. Bucheli  E. Voirol  J. López  V. Pétiard  S.D. Tanksley 《Euphytica》2002,127(2):163-177

Although the Advanced Backcross strategy has proven very useful for QTL detection in tomato, it has been used mainly in identifying QTL for agronomic traits such as yield, color, etc. Tomato flavor is an important quality characteristic, yet it has been difficult to assess flavor or traits that affect it. In this study the AB-QTL strategy was applied to four advanced backcross populations to identify QTL for biochemical properties that may contribute to the flavor of processed tomatoes, such as sugars and organic acids. A total of 222 QTL were identified for 15 traits, including flavor as assessed by a taste panel. Correlations of certain biochemicals with flavor and possible methods of assessing and improving flavor are discussed. In particular, QTL with very significant effects associated with the ratio of sugars/glutamic acid, a trait highly correlated with improved flavor, have been identified as good targets for future work in improving the flavor of tomatoes. This revised version was published online in August 2006 with corrections to the Cover Date.  相似文献   

Disturbed Mendelian segregations at isozyme marker loci in early backcrosses of Lolium multiflorum × Festuca pratensis hybrids to L. multiflorum     

M. W. Humphreys  D. Thorogood 《Euphytica》1992,66(1-2):11-18

Summary The segregation of interspecific recombinant Festuca pratensis (Fp) alleles, introgressed into the germolasm of Lolium multiflorum (Lm), at four loci (PGI/2, AcP/2, GOT/3 and BAP) is described. Heterozygous (Lm/Fp) plants were backcrossed to L. multiflorum (2n=2×=14) and subsequent BC2 Lm/Fp sibling genotypes intercrossed.In crosses between BC1 heterozygous plants (Lm/Fp) used as males and L. multiflorum, there was a reduced transmission of the F. pratensis (Donor Parent) derived alleles in the populations with PGI/2 and AcP/2 marker loci compared to the reciprocal cross but the reduction was not significantly different in those with GOT/3 and BAP markers.Two PGI/2 marked BC2 half-sib families in particular exhibited a more extreme deficiency of Fp/Fp progeny plants than anticipated from the BC2 segregations indicating possible linkage to zygotic lethals. Deficiencies of F. pratensis alleles were, in most cases, less marked in BC2 half-sib families indicating that a further round of recombination had reduced the size of the introgressed chromosome segment or that deleterious linkages had been broken. A tendency towards heterozygote advantage was found in one BAP marked halfsib family.The significance for forage grass breeding of reduced transmission rates of Donor Parent alleles in early back-cross generations especially through the male gametes is discussed.  相似文献   

仙居雄性不育大麦的研究——雄性不育性状的遗传     

吴玫君  朱汉如 《浙江大学学报(农业与生命科学版)》1992,(2)

本研究以仙居雄性不育大麦为材料,对其后代的育性作了遗传基因分析.雄性不育材料与正常品种的杂种一代为可育,杂种二代的可育株与不育株的分离比例,大多数供试品种符合3:1的理论值.以不育材料为母本,杂种F_1为父本回交,可育与不育的分离比接近1:1.以品种为母本,以杂种F_1为父本回交,其第一代为可育,第二代出现育性分离.证明仙居雄性不育大麦是受一对隐性基因控制的核不育材料.  相似文献