Resistance to Sunflower Rust and its Inheritance in Wild Sunflower Species     

Z. Quresh    C. C. Jan  T. J. Gulya 《Plant Breeding》1993,110(4):297-306

Resistance to the prevailing races of sunflower rust, Puccinia hehanthi Schw., is lacking in the commercial hybrids (Helianthus annuus L.). The objective of this study was to identify new sources of resistance to the four North American rust races in wild Helianthus species, and to determine their mode of inheritance. Seventy-eight accessions of H. annuus L., H. argophyllus Torrey and Gray, and H. petiolans Nutt. were evaluated in the greenhouse. Resistance to races 1, 2, 3, and 4 was observed in 25, 28, 15, and 26% of the plants, respectively, and 10% of the plants were resistant to all four races. Seven accessions that had a high percentage of resistant plants to all the four races were selected and one resistant plant from each accession was crossed with susceptible inbred line HA89. Three to four F₁ plants resistant to all four races from each cross were backcrossed with HA89. F₁ plants from PI-413118 × HA89 and PI 413175 × HA89 were resistant to all four races. The PI 413023 × HA89 F₁ plants were 100 % resistant to races 3 and 4 and segregated in a 3: 1 resistant (R) to susceptible (S) ratio to races 1 and 2. The other four F₁ combinations segregated 3R: IS ratios to all four races. Bc₁F₁ progenies revealed that plants from PI 413048, PI 413037, PI 413038, and PI 413171 used in the crosses possessed two dominant genes in heterozygous condition for resistance to each of the four races, whereas plants from PI 413023 possessed two dominant genes in heterozygous condition for resistance to each of races 1 and 2, and one dominant resistance gene in homozygous condition for each of races 3 and 4. Plants from PI 413118 and PI 413175 carried a single dominant gene in homozygous condition for resistance against each of the four races.  相似文献   

Segregation of genetic markers among wheat doubled haploid lines derived from wheat x maize crosses     

Kazuhiro Suenaga  Kousuke Nakajima 《Euphytica》1992,65(2):145-152

Summary Wheat doubled haploid (DH) lines were produced from the F₁ hybrid, Fukudo-komugi x Oligo Culm, through intergeneric crosses between wheat and maize. F₂ plants and 203 DH lines were analyzed for the segregation of the eight genetic markers, namely, grain proteins, grain esterases, GA-insensitivity and glume traits. The segregation in the F₂ plants fitted to the expected ratios. No deviation was observed among the DH lines, either, except for the glume pubescence. The result indicates the absence of correlation between the markers investigated and the efficiency of embryo formation in the DH lines.  相似文献   

Efficient hybridization between Lycopersicon esculentum and L. peruvianum via 'embryo rescue' and in vitro propagation     

Chen  LanZhuang Taiji  Adachi 《Plant Breeding》1996,115(4):251-256

For the transfer of valuable traits from wild species into the cultivated tomato, excised globular-stage embryos 13 and 15 days after pollination (DAP) were cultured in vitro. Plants were regenerated from interspecific crosses of Lycopersicon esculentum cv. ‘Early pink’×L. peruvianum PI270435, and backcrosses of L. esculentum‘Giban (JF) No. 1’× (‘Early pink’× PI270435). Somatic embryos and single cotyledons emerged on hypocotyl sections of the embryos. Five to nine plantlets per embryo were obtained by clonal propagation. The hybrid nature of the plants is confirmed by comparing hybrids and parents in their ability to regenerate shoots from leaf segments in vitro, by comparing plant morphology and characteristics and by chromosome number. This study describes an efficient ‘embryo rescue’ method, as well as somatic embryogenesis by clonal propagation. A novel and simple method for the characterization of the interspecific hybrids is also reported.  相似文献   

Effects of Pollination Method on Strain Cross Yield in Lucerne     

S. E. Smith  D. J. Fairbanks 《Plant Breeding》1989,102(1):79-82

Because of difficulties in pollination, control, F₁ hybrids have not been widely explioted in lucerne’ (Medicago sativa L.). Strain crossing (uncontrolled hybridization between two or more self-fertile populations with seed of the populations combined to product a “strain cross” population) represents a potentially valuable alternative procedure for exploiting heterosis in this species. Strain crosses in lucerne are typically produced using insect pollination in the field. Using hand pollination under glasshouse houses could increase the number of strain crosses available for tests of combining ability. The objective of this study was to determine whether forage yield of strain crosses produced using hand pollination were sufficiently similar to that of insect-produced populations to allow the use of the former in lucerne breeding. Forage yields of eight pairs of hand- and insect-produced strain crosses did not differ significantly in 15 of 16 pairwise comparisons and were positively correlated (r_s= 0.90) for 20 harvests at two locations. Yield amp of band produced strain crosses could be used, with reasonable accuracy to accuracy the eventual performance of strain crosses produced between the same populations using insect pollination.  相似文献   

Interactions of BA, GA3, NAA, and surfactant on interspecific hybridization of Lycopersicon esculentum × L. chilense     

L. F. Gordillo  V. D. Jolley  R. D. Horrocks  M. R. Stevens 《Euphytica》2003,129(1):15-23

Time consuming and expensive tissue culture type techniques are currently used for achieving Lycopersicon esculentum × L. chilense interspecific hybrids. The objective of this study was to determine if the number of viable hybrid seed produced directly from this wide cross could be improved by optimizing female/male parent selection when treated with various hormones in the presence or absence of a surfactant (Triton X-100). Individual or combination treatments of BA(6-benzylaminopurine), GA₃ (gibberellic acid), and/or NAA(α-naphthaleneacetic acid) were applied (both with and without surfactant)to the ovaries of two L. esculentum female parents (Fla 7613 and89S) one day following pollination by nineL. chilense accessions. Hormone applications over 1-, 3-, and 5-dayperiods were made and all treatments were compared to a distilled water control. Across all experiments 21 viable hybrids from 1920 fruits (1.1%) were obtained from2128 pollinations. There were five consistent trends observed across three experiments. First, treatments utilizing NAA produced more hybrids than any other treatment hormone. Second, eight of the total 21 hybrids resulted from five consecutive days of hormone treatments (P-value ≤0.01), and six of those eight were realized when NAA was involved. Third, the use of Triton X-100 in combination with the hormone treatments significantly reduced the number of fruits/pollination (P-value ≤ 0.01), but did not significantly reduce the number of overall viable hybrids (P-value > 0.4). Fourth, the L. chilense male parent LA2759 significantly produced the most interspecific hybrids (P-value ≤ 0.04),seven hybrids from 295 fruits, compared to the male parent LA130 which did not produce any hybrids (from 293 fruits) -other accessions were intermediate. Fifth, nearly ten times more hybrids were produced from crosses with Fla 7613 than with 89S. These experiments provide a foundation for future studies to discern specific concentrations, timing and frequency of application of NAA and possibly, GA₃, to efficiently produce interspecific hybrids of L. esculentum × L. chilense. This revised version was published online in August 2006 with corrections to the Cover Date.  相似文献   

Development of self-incompatible Brassica napus: (I) introgression of S-alleles from Brassica oleracea through interspecific hybridization   总被引：1，自引：0，他引：1  

V. L. RIPLEY  W. D. BEVERSDORF 《Plant Breeding》2003,122(1):1-5

Cultivars in Brassica napus var. oleifera, a self‐pollinating, self‐compatible species, have traditionally been developed as open‐pollinated lines or populations. Significant yield gains in this species have been realized through the exploitation of heterosis. Commercial hybrid production has been possible as a result of the development of a number of pollination control systems. Self‐incompatibility was transferred from B. oleracea var. italica to B. napus var. oleifera through interspecific hybridization. The response to interspecific pollination, as measured by pod elongation and initial stages of ovule development, was genotype dependent, and two highly responsive B. napus genotypes were identified. Embryo rescue was used to produce the interspecific hybrids. Isoelectric focusing of stigma proteins was used to identify S‐alleles in the interspecific hybrids to facilitate backcrossing. Segregation of the S‐locus through a series of back‐crosses to B. napus was complicated by aneuploidy; however, the S‐locus was found to segregate as a single gene. Usefulness of B. oleracea as a source of S‐alleles for pollination control in B. napus is discussed.  相似文献   

New interspecific rice genome constructions obtained by symmetric cell fusion     

Y. Y. Feng    H. Takahashi    H. Akagi    K. Mori 《Plant Breeding》2006,125(4):403-404

Newly released rice varieties are mostly progenies of common commercial cultivars and so most gene sources for rice breeding have closely related genotypes. Protoplast fusion technique is a method that can produce hybrid plants in one‐step within a desired cultivar. To introduce new genetic diversity into rice‐breeding materials, hybrids between Oryza sativa L. (AA) and Oryza punctata Kotschy ex Steud. (BBCC) were generated by symmetric protoplast fusion. The genomic distribution in interspecific somatic hybrids was investigated by multi‐colour genomic in situ hybridization. Differences in chromosome numbers were observed not only between different somatic hybrid plants but also within individual hybrid plants. Chromosomal reduction of the A genome was found in two somatic hybrids. These results suggest that it is possible to reconstruct new interspecific rice genomes. Chromosomal reduction in interspecific somatic hybrids may be used to generate breeding lines with novel chromosomal constitutions.  相似文献   

棉属两个种间杂种一代雌配子体发育的比较研究     

聂以春  刘金兰  王坤波  黎绍惠 《棉花学报》1997,(1)

用常规石蜡切片法，对草棉×异常棉（Ａ１×Ｂ１）、草棉×长须棉（Ａ１×Ｂ３）两个杂种一代与各自双亲之一的异常棉和长须棉的雌配子体发育进行了比较研究。结果表明，两个杂种一代大孢子母细胞减数分裂的起始时间比亲本推迟１～２ｄ，减数分裂过程持续时间多２ｄ，雌性败育主要发生在四分孢子到大孢子期间，Ａ１×Ｂ１Ｆ１和Ａ１×Ｂ３Ｆ１败育胚囊分别占观察总数的６６．７％和７１．０％，且在单核至成熟胚囊期间也有较多的异常胚囊类型。败育的主要原因是产生胚囊的大孢子染色体组成不完整。两个杂种在开花前一天的花蕾中，正常成熟的胚囊分别占１５．４％和１０．４％，表明这两个野生种与栽培种草棉亲缘关系较近  相似文献   

Pollen–pistil interaction in the inter-specific crosses of Sesamum sp     

S. Ganesh Ram  K. Sundaravelpandian  M. Kumar  K. K. Vinod  J. R. Kannan Bapu  T. S. Raveendran 《Euphytica》2006,152(3):379-385

The wild species of Sesamum have long been recognized as an important source of many valuable pest and disease resistance genes and other novel traits such as male sterility and plant type for the cultivated taxon. Utilization of these species in crop improvement is marginal because of their inherent low crossability with the cultigen. An understanding of the biological nature of incompatibility systems that impede hybridization offers tools for successful introgressions into cultivated sesame. The objective of this investigation was to observe pollen germination and pollen tube growth in cross pollinated S. indicum pistils as an indicator of pre-zygotic barriers operating in wide crosses involving S. indicum. Three wild species: S. alatum, S. radiatum and S. laciniatum were used as pollen donors in hybridization with S. indicum. In the cross S. indicum × S. alatum 85.23% of pollen grains germinated and pollen tubes reached ovaries within 8 h after pollination. In other two crosses, S. indicum × S. laciniatum and S. indicum × S. radiatum the level of incompatibility was high as evidenced by a reduced pollen germination and slow rate of pollen tube growth. Measures to circumvent incompatibility in these crosses to produce interspecific hybrids are discussed.  相似文献   

Low relative humidity increases haploid production in durum wheat X maize crosses     

J. Ballesteros    C. García-Llamas  M. C. Ramírez  A. Martín  W. E. Weber 《Plant Breeding》2003,122(3):276-278

Haploidization is a useful tool for genetic analysis and plant breeding, but a consistent and satisfactory protocol for haploid production has been difficult to achieve in durum wheat. The objective of this study was to analyze the influence of the relative humidity of the environment, when culturing detached tillers during the production of haploids plants in durum wheat by the maize method. Thirty‐eight F3 lines from eight crosses of durum wheat were pollinated with bulked pollen from three commercial maize hybrids. A mixture of 2‐4D and dicamba was used as a hormone treatment. The numbers of caryopses, embryos and haploids plants were scored. When 65‐85% (light‐dark) humidity was substituted for 55‐65% the number of haploids per spike increased notably. This increased frequency was largely attributed to a rise in the production of generated caryopses. On average, 15.2 vs. 9.3 caryopses, 5.0 vs. 2.8 embryos, and 3.1 vs. 0.6 haploid plants, per spike, were produced under low and high humidity regimes, respectively.  相似文献