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1.
Under field conditions in Germany over three growing seasons the pleiotropic effects on yield and its components of four sets of near isogenic lines carrying the GA insensitive dwarfing alleles Rht1, Rht2, Rht3, Rht1+2, Rht2+3 or rht (tall) in four different genetical backgrounds were examined together with 24 single chromosome recombinant lines segregating for the GA sensitive dwarfing gene Rht8 and the gene for day-length insensitivity Ppd1 in a ‘Cappelle-Desprez’ background. For the GA insensitive semi-dwarfs it was shown that in all three years a higher number of grains per ear was accompanied by a lower grain weight. Depending on the climatic conditions in a particular year, the increase in grain number was sufficient to compensate for the reduction in grain size and resulted in higher yields. For the Ppd1 allele yield advantages were found for wheats grown under environmental conditions of middle Europe.  相似文献   

2.
Summary Genetic analysis of a new weak source of GA-insensitivity derived from Saitama 27 showed that it was controlled by a single gene located on chromosome 4A and allelic to Rht1 and Rht3. the gene was shown to be present in many Italian and Yugoslavian varieties suggesting a selective advantage in some breeding programmes. Varietal comparisons indicated that the gene reduces height by around 11 per cent. This was combined with an increase in spikelet fertility and in the total number of grain developing in the ear. In this initial experiment a reduction in grain size eliminated the advantages of increased grain number. Following development of isogenic lines in a number of varietal backgrounds the true potential of the gene will be determined.  相似文献   

3.
Rht12, a dominant dwarfing gene of wheat, was shown to be located distally on the long arm of chromosome 5A. Lack of recombination with the awn inhibitor B1 suggested that Rht12 is cither tightly linked to this gene or is, in this material, a pleiotropic expression of the gene. Linkage to β-Amy-A1 was also very tight, indicating that Rht12 is present on the segment of chromosome SAL ancestrally translocated from 4AL. The close linkage to β-Amy-A1 also suggests that Rht12 is not a homoeoallele of the commercially important GA-insensitive dwarfing genes. Analysis of near-isogenic lines in a number of genetic backgrounds showed that Rht12 reduces height without altering ear size and significantly increases spikelet fertility. However its successful utilization in breeding programmes will require careful selection since in some backgrounds the gene reduces grain numbers and grain size. In all backgrounds, Rht12 delayed ear emergence time by around 6 days. A delay of this magnitude could, in many environments, adversely affect yield if it is not neutralized by altering the balance of other genes determining ear emergence time.  相似文献   

4.
In wheat, semidwarfism resulting from reduced height (Rht)‐B1b and Rht‐D1b was integral to the ‘green revolution’. The principal donors of these alleles are ‘Norin 10’, ‘Seu Seun 27’ and ‘Suwon 92’ that, according to historical records, inherited semidwarfism from the Japanese landrace ‘Daruma’. The objective of this study was to examine the origins of Rht‐B1b and Rht‐D1b by growing multiple seed bank sources of cultivars comprising the historical pedigrees of the principal donor lines and scoring Rht‐1 genotype and plant height. This revealed that ‘Norin 10’ and ‘Suwon 92’ sources contained Rht‐B1b and Rht‐D1b, but the ‘Seu Seun 27’ source did not contain a semidwarf allele. Neither Rht‐B1b nor Rht‐D1b could be definitively traced back to ‘Daruma’, and both ‘Daruma’ sources contained only Rht‐B1b. However, ‘Daruma’ remains the most likely donor of Rht‐B1b and Rht‐D1b. We suggest that the disparity between historical pedigrees and Rht‐1 genotypes occurs because the genetic make‐up of seed bank sources differs from that of the cultivars actually used in the pedigrees. Some evidence also suggests that an alternative Rht‐D1b donor may exist.  相似文献   

5.
N. Tian  Z.-Q. Liu 《Plant Breeding》2001,120(1):79-81
In order to develop genie male‐sterile lines with a blue seed marker, male‐sterile plants, controlled by a dominant nuclear gene Ms2, were used as female parents against a 4E disomic addition line ‘Xiaoyan Lanli’(2n= 44, AABBDD+4EII) as the male parent to produce monosomic addition lines with blue seed. Male‐sterile plants from the monosomic addition lines were pollinated with durum wheat for several generations and in 1989 a male‐sterile line with the blue grain gene and the male‐sterile gene Ms2 on the same additional chromosome was detected and named line 89‐2343. Using this line, the blue seed marker was successfully added to a short male‐sterile line containing Ms2 and Rht10. The segregation ratios of male sterility and seed colour as well as the chromosome figurations of different plants indicated that the blue grain genes, Ms2 and Rht10 were located on the same additional chromosome. Cytological analysis showed that the blue marker male‐sterile lines in durum wheat and common wheat were monosomic with an additional chromosome 4E. The inheritance ratio for blue seed male‐sterile plants and white seed male‐fertile plants was 19.7% and 80.3%, respectively, in common wheat. The potential for using blue marker sterile lines in population improvement and hybrid production is discussed.  相似文献   

6.
The photoperiod‐insensitive barley mutant ‘Atsel’, carrying the recessive gene ea7, was studied together with the donor variety ‘Atlas’ (wild‐type, Ea7) under different daylengths with the aim of analysing pleiotropic effects. Grown under long and short photoperiods ‘Atsel’ flowered about 10 days and 34 days, respectively, earlier than ‘Atlas’. The significantly shorter life‐cycle of the photoperiod‐insensitive mutant resulted in several changes of plant morphology. Tillering, plant height, number of leaves and number of internodes were reduced. A lower number of florets per main spike was observed for ‘Atsel’, but only in the long photoperiod experiment. Finally, photoperiod insensitivity combined with a lower grain yield per plant was most pronounced under long‐day treatment. The data are comparable with results obtained from single chromosome recombinant lines of wheat that have differences in their photoperiod response caused by the genes Ppd1 or Ppd2.  相似文献   

7.
D. Struss    U. Bellin  G. Röbbelen 《Plant Breeding》1991,106(3):209-214
By interspecific hybridization within the genus Brassica, trigenomic haploids were produced and back-crossed four times with B. napus, variety ‘Andor’. From this material, monosomic B-genome chromosome addition lines were selected with the extra chromosome derived from three different B-genome sources, i.e., B. nigra (BB), B. carinata (BBCC), and B. juncea (AABB). After selfing and/or microspore culture, disomic addition lines were obtained. Meiotic behavior was studied of the trigenomic hybrids, the pentaploid BC1 plants, and the monosomic addition lines. The addition lines were shown to possess cytological stability and good fertility.  相似文献   

8.
Summary The influence of genes affecting the plant growth habit in wheat (Rht8 and Ppd1) and rye (ct1 and ct2) on tissue culture response was studied using immature embryos. Whereas the semi-dwarfing gene Rht8 seems to promote only a minor effect, the day-length sensitive allele ppd1 determined a major increase in callus growth and regeneration ability. With regards to their tissue culture efficiency, the four alleles studied could be ranked as follows: ppd1>Rht8>rht8>Ppd1.In contrast to wheat, the GA insensitive semi-dwarfing genes of rye (ct1 and ct2) appear not to influence in vitro response.  相似文献   

9.
Chromosomal location of dwarfing gene Rht12 in wheat   总被引:2,自引:0,他引:2  
J. Sutka  G. Kovács 《Euphytica》1987,36(2):521-523
Summary The chromosomal location of the dwarfing gene Rht12 in the mutant winter wheat Karcagi 522M7K was investigated using F2 monosomic analysis. The segregation ratio for F2 progenies of Chinese Spring monosomics × Karcagi 522M7K, and that of Cheyenne monosomics × Karcagi 522M7K indicated that the near complete dominant dwarfing gene Rht12 is located on chromosome 5A. The heterozygous and hemizygous states of the genes Rht12 have the same effect on plant height.  相似文献   

10.
Summary Wheat varieties tend to be chromosomally unstable producing on average 2–3% of plants with abnormal chromosome numbers. A number of semi dwarf wheat varieties, carrying the gibberellic acid insensitive dwarfing genes Rht1 or Rht2, have been seen to produce distinct tall off types due to reduction in dosage of the chromosome carrying the dwarfing gene. The UK variety Brigand, carrying Rht2 on chromosome 4D, produced very distinct tall off types when this chromosome was reduced in dosage. The frequency of tall off types was sufficiently high to cause the variety to fail United Kingdom statutory uniformity tests. An attempt to prevent the loss of chromosome 4D was made by constructing translocation chromosomes involving the short arm of chromosome 4D, which carries Rht2, and the long arm of chromosome 4S l from Aegilops sharonensis, which carries a gene(s) conferring preferential transmission. The work in this paper describes the field evaluation of two lines carrying 4DS.4DL-4S l L translocations, and demonstrates their success in preventing spontaneously occurring monosomy of chromosome 4D in semi-dwarf wheats.  相似文献   

11.
K. Murai 《Plant Breeding》2002,121(4):363-365
A ‘two‐line system’ using photoperiod‐sensitive cytoplasmic male sterility (PCMS) caused by Aegilops crassa cytoplasm under a long‐day photoperiod ( 15 h) has been proposed as a new means of producing hybrid varieties in common wheat. The PCMS line is maintained by self‐pollination under short‐day conditions, and hybrid seeds can be produced through outcrossing of the PCMS line with a pollinator under long‐day conditions. Two kinds of fertility restoration systems against the PCMS are known. One is involved with a set of multiple fertility‐restoring (Rf) genes in the wheat cultivar ‘Norin 61’ located on (at least) chromosomes 4A, 1D, 3D and 5D. The other is controlled by a single dominant major Rf gene, Rfd1, located on the long arm of chromosome 7B in the wheat cultivar ‘Chinese Spring’. To examine the degree of fertility restoration by these two systems, nine PCMS lines were crossed with ‘Norin 61’ and ‘Chinese Spring’ as the restorer lines, and the F1 hybrids were investigated. The degree of fertility restoration was estimated by comparing the seed set rates in the F1 hybrids having the Ae. crassa cytoplasm and those with normal cytoplasm. The results revealed that the fertility restoration ability of a set of multiple Rf genes in ‘Norin 61’ was higher than that of the Rfd1 gene in ‘Chinese Spring’.  相似文献   

12.
A.J. Worland  E.J. Sayers  V. Korzun 《Euphytica》2001,119(1-2):157-161
A microsatellite marker WMS261 developed at I.P.K., Gatersleben,Germany, co-segregates with the semi-dwarfing gene Rht8. Screens ofover 800 wheat varieties from 20 countries show 90% carry WMS-261alleles with 165, 174 or 192 base pairs (bp). The 192bp allele diagnosticof Rht8 occurs in most screened Southern European varieties. Anallele with 165 bp occurs in the majority of CIMMYT Mexican varieties andin most varieties bred in countries that utilize CIMMYT germplasm.Agronomic studies of single chromosome recombinant line mappingpopulations segregating for WMS 261 alleles with 165, 174 or 192 bp,show compared to the 174bp allele the 192bp allele reduces height byaround 8 cm and the 165 bp allele increases height by around 3cm. Theresults indicate the importance and widespread utilization of Rht8 asa dwarfing gene in southern Europe and suggest an adaptative significanceto the height promoting 165 bp allele in CIMMYT material.  相似文献   

13.
Liu B.  H 《Plant Breeding》1987,98(3):266-267
The genes Ms2 for male sterility and Rht10 for dominant dwarfing located on the short arm of chromosome 4D in common wheat arc closely linked. Male sterile, dwarf F1 plants from the cross of male sterile‘Chinese Spring’× dwarf‘Ai-bian’were backcrossed with the variety‘Chinese Spring, From this offspring a spontaneous chromosome translocation was isolated resulting in a recombinant male sterile and dwarf genotype.  相似文献   

14.
Toshiaki Yamada 《Euphytica》1990,50(3):221-239
Summary The GA response, Rht genes and culm length of 133 Norin varieties, 6 breeding lines and 16 landraces of Japanese wheat were investigated. Out of 133 Norin varieties tested, 103 were GA-insensitive and 30 GA-responsive. The 6 breeding lines were all GA-insensitive. Out of 16 landraces tested, 10 were GA-insensitive and 6 GA-responsive. Among the 10 GA-insensitive landraces, only Daruma had a Rht1 genotype. The other 9 had a Rht2 genotype. None of the landraces tested carried both Rht1 and Rht2 or Rht3. Out of the 103 GA-insensitive Norin varieties, 22 carried only Rht1, another 79 carried only Rht2, and only Norin 10 and Kokeshikomugi carried both Rht1 and Rht2. No tested variety carried Rht3. Some Norin varieties carrying Rht2 showed tall culms comparable to that of the rht tester line Chinese Spring. These results suggest that these varieties had a nullifier or modifier gene(s) or height promoting genes in the background controlling the height-reducing effect of Rht2. Conversely, six GA-responsive Norin varieties were as short as Akakomugi which carries the GA-responsive Rht genes, Rht8 and Rht9. The also seemed to carry a GA-responsive Rht gene or genes, and moreover all but one may carry gene(s) other than the Akakomugi genes. The origin of Rht1 and Rht2 of Norin 10 was speculated on the GA-response and Rht genotypes of its related varieties and landraces.  相似文献   

15.
Increasing grain yield is a key breeding goal in bread wheat. Several authors have suggested that a spike fertility index (SF), that is the quotient between grain number per unit spike (GNS) and spike chaff dry weight (SCDW), could be used as a yield‐related selection criterion, especially if molecular markers were available. Here, the effects of Ppd‐B1 and Ppd‐D1 genes on SFm, GNSm and SCDWm (measured at maturity) and the relationship between these variables were analysed in field experiments carried out during three crop seasons at Balcarce, Argentina, on an association mapping population of 100 bread wheat cultivars of diverse origin released in Argentina between 1927 and 2010. Results show that both Ppd‐B1 and Ppd‐D1 are associated with SFm with similar effects. Cultivars with insensitive alleles at both genes showed a mean SFm 9.2% greater than those with sensitive alleles at both genes; at each gene, difference in SFm between insensitive and sensitive alleles was ~4.5%. In turn, each gene showed a differential effect on GNSm and SCDWm, as Ppd‐B1 was more related to SCDWm, whereas Ppd‐D1 was only related to GNSm. Although more research needs to be carried out in order to ascertain the physiological pathway by which these genes affect spike fertility, this study represents a first approximation in order to elucidate the molecular and genetic basis underlying SF and related physiological traits.  相似文献   

16.
K. murai 《Plant Breeding》1997,116(6):592-594
Triticum aestivum cv. Norin 26 with the Aegilops crassa cytoplasm becomes almost completely male sterile when grown under a long-day condition (15 h of light or longer), but is highly male fertile under a short-day condition (14.5h or less). This type of male sterility is called photoperiod-sensitive cytoplasmic male sterility (PCMS). Genetic analyses were made of the fertility-restoring (Rf) genes effective against PCMS that are present in T. aestivum cv. Norin 61. Conventional and monosomic studies indicated that restoration of fertility is controlled by multiple Rf genes located on at least four chromosomes: 4 A, 1D, 3D and 5D. The genetic mechanism of fertility restoration by the genes of‘Norin 61’differs from the mechanisms reported for‘Chinese Spring’and a‘Norin 26’mutant line.  相似文献   

17.
Reduced height genes are the genetic basis of the “green revolution”. Two agronomically important gibberellic acid (GA)-insensitive genes, Rht-B1b (Rht1) and Rht-D1b (Rht2), localised on chromosomes 4BS and 4DS, respectively, and the GA-responsive gene Rht8, localised on chromosome 2DS, were introduced into many cultivars worldwide. An alternative GA-insensitive gene Rht-B1e (=Rht11) was introduced into Russian wheat cultivars. In this study, we investigated the importance of Rht-B1b, Rht-B1e, Rht-D1b and Rht8 in south Russian bread wheat cultivars. The cultivars were divided into five groups: (1) Rht8c; (2) Rht-B1b; (3) Rht-B1b, Rht8; (4) Rht-B1e, Rht8; and (5) Rht-D1b, Rht8. In the Krasnodar region of south Russia 3,222,321 ha were evaluated for estimating the commercial value of each of these genes in 2009–2011. The results showed that coupling Rht-B1e with Rht8 or Rht-B1b with Rht8 was more successful compared with the effects of other genes or their combinations. The average yield of cultivars carrying Rht-B1e exceeded the average yield of cultivars from the other groups. Our study demonstrates that Rht-B1e can be recommended for use in breeding programs and the presence of a molecular marker for this allele simplifies its transfer to elite wheat germplasm.  相似文献   

18.
TIBL-1RS wheat-rye translocation cultivars utilized in wheat programmes worldwide carry powdery mildew resistance gene Pm8. Cultivar‘Amigo’possesses resistance gene Pm17 on its TIAL-1RS translocated chromosome. To be able to use Pm17efficiently in breeding programmes, this gene was transferred to a TIBL-1RS translocation in line Helami-105, and allelism between Pm8 and Pm17was studied. The progenies of the hybrids in the F2 generation and F3 families provided evidence that the two genes are allelic. Genetic studies using monosomic analyses confirmed that in cultivar‘Amigo', Pm17 and leaf rust resistance gene Lr24 are located on a translocated chromosome involving 1 A and 1B, respectively.  相似文献   

19.
W. Tadesse    S. L. K. Hsam    F. J. Zeller 《Plant Breeding》2006,125(4):318-322
A total of 50 wheat (Triticum aestivum L.) cultivars were evaluated for resistance to tan spot, using Pyrenophora tritici‐repentis race 1 and race 5 isolates. The cultivars ‘Salamouni’, ‘Red Chief’, ‘Dashen’, ‘Empire’ and ‘Armada’ were resistant to isolate ASC1a (race 1), whereas 76% of the cultivars were susceptible. Chi‐squared analysis of the F2 segregation data of hybrids between 20 monosomic lines of the wheat cultivar ‘Chinese Spring’ and the resistant cultivar ‘Salamouni’ revealed that tan spot resistance in ‘Salamouni’ was controlled by a single recessive gene located on chromosome 3A. This gene is designated tsn4. The resistant cultivars identified in this study are recommended for use in breeding programmes to improve tan spot resistance in common wheat.  相似文献   

20.
V. Korzun    M. Röder    A. J. Worland  A. Börner 《Plant Breeding》1997,116(3):227-232
For intrachromosomal mapping of the dominant GA-sensitive dwarfing gene Rht12 and the vernalization response gene Vrn1 on chromosome 5 A, an F2 population was established using a wide (synthetic) wheat cross. In addition to restriction fragment length polymorphism (RFLP) probes four microsatellite markers were incorporated. Rht12 was mapped distally to four RFLP loci (Xmwg616, Xpsr164, Xwg114, Xpsr1201) and three microsatellite markers (Xgwm179, Xgwm410, Xgwm291), known to be located on the segment of chromosome SAL which was ancestrally translocated and is homoeologous to Triticeae 4 L. The map position of Rht12 suggests that it is homoeologous to the dominant GA-sensitive dwarfing gene Ddw1, present on chromosome 5RL. The vernalization response gene Vrn1 showed linkage to Xwg644, as might be expected from comparative maps.  相似文献   

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