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41.
Summary A study was undertaken to evaluate the breeding behaviour and to identify a spontaneously produced putative chromosomal deletion in the winter wheat (Triticum aestivum L. em. Thell.) cv Norstar. Male and female transmission studies of plants heterozygous for the deletion chromosome indicated 9.5% and 48.8% transmission through the pollen and the egg, respectively. Meiotic analyses of progeny from deletion heterozygotes indicated that the deletion chromosome was eliminated from half of the plants, which agreed with the male and female transmission frequencies. Testcrosses of the deletion chromosome with telocentrics and nullisomic-tetrasomic combinations suggested that the deletion involved the long arm of chromosome 5D. This was confirmed by restriction fragment length polymorphism (RFLP) analysis. Also, monosomic plants obtained in progeny of deletion heterozygotes were shown to be monosomic for 5D. Studies of plants homozygous for the deletion showed relatively normal pairing between the deletion chromosomes, and with the short arm (5DS), but not the long arm (5DL). Deletion homozygotes were self-sterile, and morphologically similar to plants nullisomic for 5D, but plants that also contained 5DL, or a homoeologous chromosome were self-fertile and had normal morphology. Studies of chromosome morphology indicated that the deletion chromosome was metacentric, and the length of the long arm was reduced by approximately 60%. RFLP studies showed that, in terms of genetic distance, 90% of the arm was missing. 相似文献
42.
Genetic diversity within Australian wheat breeding programs based on molecular and pedigree data 总被引:8,自引:0,他引:8
124 wheat cultivars and breeding lines were screened with 19 microsatellite (SSR) loci generating 160 scorable bands which
were used to construct a genetic distance (GD) matrix. A distance matrix based on coefficient of parentage (COP) scores was
also generated for the cultivars for which good pedigree records were available. The SSR and COP data for 101 of the wheat
cultivars were compared with genetic distance scores obtained using1898 scorable restriction fragment length polymorphism
(RFLP) bands previously generated. Phylograms were generated based on the SSR, RFLP,combined SSR and RFLP and COP data. The
standardised Mantel's Z test showed that the distance matrices generated from all of the data sets were significantly correlated.
Bootstrap analysis showed that, although the SSR and RFLP data were correlated, a large number of SSR loci are required for
determining robust genetic relationships between large numbers of cultivars. In addition, accurate pedigree records are needed
to determine genetic relatedness using COP. The molecular data were also used to determine the level of genetic variability
within breeding programs and to assess the impact of the introduction of semidwarf and other germplasm. The results showed
that the level of genetic diversity in Australian wheat cultivars has increased over time and that in particular, the introduction
of semidwarf germplasm resulted in an increase in the overall diversity.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
43.
P.N. Sharma Y. Ketipearachchi K. Murata A. Torii S. Takumi N. Mori C. Nakamura 《Euphytica》2003,129(1):109-117
We have constructed a linkage map of the rice brown planthopper (BPH)resistance gene, Bph1. RFLP and AFLP markers were selected by thebulked segregant analysis and used in the mapping study of 262 F2sthat were derived from a cross of `Tsukushibare', a susceptible japonica cultivar, and `Norin-PL3', an authentic japonicaBph1-introgression line. Twenty markers were mapped within a 28.9-cMregion containing the Bph1 locus on the long arm of rice chromosome12. Combining the result of segregation analysis of BPH resistance by themass seedling test and that of the markers, the Bph1 locus wasmapped within a 5.8-cM region between two flanking markers. The closestAFLP markers, em5814N and em2802N, was at 2.7 cM proximal to theBph1 locus. Together with the previously constructed high-resolutionmap of bph2 locating the locus at ca. 10 cM proximal to the Bph1 locus, this improved version of the linkage map would facilitatepyramiding these two important BPH resistance genes. 相似文献
44.
Genetic control of flowering time in sorghum was investigated using a recombinant inbred lines population derived from a cross
between IS 2807, a slightly photoperiod sensitive tropical caudatum landrace, and IS 7680,a highly photoperiod sensitive tropical
guinea landrace. Progenies were sown with their parents at six different dates between 1995 and 1997 in Burkina Faso. Direct
field measures and synthetic measures derived from the implementation of a model were used to characterize the photoperiod
response. Emphasis was put to identify the most relevant traits to account for Basic Vegetative Phase (BVP) and photoperiod
sensitivity sensus stricto. One QTL was detected on Linkage Group (LG) F for the traits related to BVP. Two QTLs were detected on LGs C and H for the
traits related to the photoperiod sensitivity sensus stricto. This gives credit to at least partially independent genetic determinisms for those two components of photoperiod response.
Evidences for possible orthology of the QTLs detected here with other QTLs and major genes involved in flowering time of sorghum
and rice are discussed.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
45.
Genomic in situ hybridization (GISH) and restriction fragment length polymorphism (RFLP) were used to identify the Leymus multicaulis (XXNN, 2n = 28) chromosomes in wheat-L. muliticaulis derivatives. Fifteen lines containing L. multicaulis alien chromosomes or chromosomal fragments were identified. All alien chromosomes or fragments in these 15 lines were from
the X genome and none were from the N genome. Eleven L. multicaulis disomic addition lines and four translocation-addition lines were identified with chromosome rearrangements among homoeologous
groups 2, 3, 6 and 7. Only homoeologous group 1 lacked rearrangements in addition or translocation chromosomes. The results
revealed that translocation in non-homoeologous chromosomes widely exists in the Triticeae and therefore it is necessary to
identify the alien chromosomes
(segments) in a wheat background using these combined techniques. During the course of the work, probe PSR112, was found to
detect X genome addition lines involving L. multicaulischromosomes. This may prove to be a valuable probe for the identification of alien chromosomes in a wheat background.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
46.
Genetical Studies on the Mode of Inheritance and Localization of the amo1 (High Amylose) Gene in Barley 总被引:1,自引:0,他引:1
In the high amylose starch mutant ‘Glacier AC38’, a single recessive gene designated amo1 is responsible for an amylose content of up to 45%. A rapid technique was established in order to evaluate the amylose/amylopectin ratio in half kernels. To localize this gene, crosses with multiple marker lines and trisormes were conducted. In addition, RFLP markers were used to determine their mapping distance to amo1. Two markers are located 2 cM and 7 cM, respectively, from amo1 on chromosome 5S (1HS). The relationship between the wx and amo1 genes was also examined and the role of the amo1 gene in starch synthesis is discussed. 相似文献
47.
Rhizomania, one of the most important diseases of sugar beet, is caused by beet necrotic yellow vein virus, a Furovirus vectored by the fungus Polymyxa betae Keskin. Reduction of the production losses caused by this disease can only be achieved by using tolerant cultivars. The objective of this study was the identification and mapping of random amplified polymorphic DNA (RAPD) markers linked to a rhizomania resistance gene. The RAPD markers were identified using bulked segregant analysis in a segregating population of 62 individuals derived by intercrossing plants of the resistant commercial hybrid GOLF, and the resistance locus was positioned in a molecular marker linkage map made with a different population of 50 GOLF plants. The resistance locus, Rr1, was mapped to linkage group III of our map of Beta vulgaris L. ssp. vulgaris, which consisted of 76 RAPDs, 20 restriction fragment length polymorphisms (RFLPs), three sequence characterized amplified regions (SCARs) and one sequence tagged site (STS). In total, 101 molecular markers were mapped over 14 linkage groups which spanned 688.4 cM with an average interval length of 8.0 cM. In the combined map, Rr1 proved to be flanked by the RAPD loci RA4111800 and AS71100 at 9.5 and 18.5cM, respectively. Moreover, in our I2 population, we found that a set of markers shown by Barzen et al. (1997) to be linked to the ‘Holly’ type resistance gene was also linked to the ‘GOLF’-type resistance gene. These results appeared to indicate that the rhizomania resistance gene present in the GOLF hybrid could be the same gene underlying resistance in ‘Holly’-based resistant genotypes. Two other explanations could be applied: first, that two different alleles at the same locus could have been selected; second, that two different genes at two different but clustered loci underwent the selection process. 相似文献
48.
Z.Y. Xin Z.Y. Zhang X. Chen Z.S. Lin Y.Z. Ma H.J. Xu P.M. Banks P.J. Larkin 《Euphytica》2001,119(1-2):163-167
We developed some wheat-Th. intermedium translocation lines,Yw642, Yw443 and Yw243, etc., showing good BYDV resistance from L1by induced homoeologous pairing using CS ph mutant. Characterization ofthese wheat lines was carried out by GISH and RFLP analysis. The resultsof GISH showed that the lines, YWw42, Yw443 and Yw243, etc., arehomozygous wheat-Th. intermedium translocation lines, in which thechromosome segments of Th. intermedium were transferred to thedistal end of a pair of wheat chromosomes. RFLP analysis indicated that thetranslocation chromosome of the wheat lines is T7DS · 7DL-7XL. Thebreakpoint of the translocation is located on the distal end of 7DL, betweenXpsr965 and Xpsr680 about 90–99 cm from the centromere. The BYDVgene is located on the distal end of 7XL around Xpsr680, Xpsr687 andXwg380. The RFLP markers of psr680, psr687 and wg380 werecosegregated with the BYDV resistance respectively and could be used formolecular assisted selection (MAS) in wheat breeding program for BYDVresistance. 相似文献
49.
中国水稻白叶枯病菌系染色体DNA的RFLP谱型的初析 总被引:5,自引:0,他引:5
用2个DNA探针pJEL101和pBASavrXa10对78个水稻白叶枯病菌系进行RFLP分型,以分析其群体结构和遗传多样性。分别鉴定出16种RFLP标记带的谱型。以彼此的带位相似率达85%为界,可分为簇。参试菌系的群体遗传多样性为0.77(用pJEL101),和0.83RFLP谱型分析表明:我国多数病原型为杂合组群。白叶枯病菌系的分子表现型的变异,远远大于致病型,两个探针都能有效分析我国菌系的群 相似文献
50.
Orientation and integration of the classical and molecular genetic maps of chromosome 11 in rice 总被引:8,自引:0,他引:8
M. L. P. Abenes R. E. Tabien S. R. McCouch R. Ikeda P. Ronald G. S. Khush N. Huang 《Euphytica》1994,76(1-2):81-87
Summary The classical genetic map and molecular map of rice chromosome 11 were oriented to facilitate the use of these maps for genetic studies and rice improvement. Three morphological markers (d-27, z-2, and la) were crossed to a rice breeding line, IRBB21, which has the Xa-21 gene for bacterial blight resistance. Three F2 populations were analyzed with RFLP markers known to be located on chromosome 11. Segregation analysis of molecular markers and morphological markers was used to construct an RFLP map for each population. The recombination frequency between markers varied from population to population although the marker order on the maps was the same for all three populations. Based on a common set of markers mapped in the three populations, an integrated map was generated consisting of both RFLP and morphological markers. The genetic distance between markers on this map was determined by taking a weighted average of the data from the three populations. The oriented map serves as a bridge to understand the relationship between the classical and molecular linkage maps. Based on this information, the location of several genes on the classical map can be approximated with respect to RFLP markers without having to map them directly. 相似文献