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1.
Summary Atrazine resistant Brassica napus × B. oleracea F1 hybrids were backcrossed to both parental species. The backcrosses to B. napus produced seeds in both directions but results were much better when the F1 hybrid was the pollen parent. Backcrosses to B. oleracea failed completely but BC1s were rescued by embryo culture both from a tetraploid hybrid (2n = 4x = 37; A1C1CC) and sesquidiploid hybrids (2n = 3x = 8; A1C1C). Progeny of crosses between the tetraploid hybrid and B. oleracea had between 25 and 28 chromosomes. That of crosses between the sesquidiploid hybrid and B. oleracea had between 21 and 27. A few plants that had chromosome counts outside the expected range may have originated from either diploid parthenogenesis, unreduced gametes or spontaneous chromosome doubling during in vitro culture. Pollen stainability of the BC1s ranged from 0% to 91.5%. All the BC1s to B. oleracea were resistant to atrazine. 相似文献
2.
Gilbert D. McCollum 《Euphytica》1981,30(3):855-859
Summary Alloplasmic male-sterile Brassica oleracea L. was synthesized in a backcrossing program through amphidiploid Raphanobrassica by using Early Scarlet Globe radish (Raphanus sativus L.) as the donor of cytoplasm and B. oleracea broccoli and cabbage as recurrent pollen parents. Persistence of radish chromosomes and high female sterility were encountered in the first four backcrosses. Following use of colchiploid 4x broccoli as pollen parent, a BC5 plant was obtained that had 2n=3x+1=28 chromosomes, improved seed set, and no radish traits. The BC6 with recurrent 2x broccoli contained male-sterile plants with 2n=18 or 19 chromosomes, increased seed set, and broccoli morphology. Subsequent generations segregated for male-sterile and restored male-fertile plants, some with variable development of stamens and pollen. Leaf color of the alloplasmic plants, especially seedlings, was lighter green than normal. 相似文献
3.
Summary The first backcross and F2 progenies from triploid F1 and tetraploid F1 hybrids between B. napus and 2x and 4x B. oleracea ssp. capitata (cabbage) were studied for their general morphology, resistance to race 2 of the clubroot pathogen, chromosome number and meiotic chromosome behavior. No linkage was apparent between resistance and the major morphological characters. Unreduced gametes played a large part in the successful formation of seed of the B1 and F2 progeny. B1 plants with low chromosome numbers were selected for use in recurrent backcrosses. The potential use of anther culture to extract gametic progenies from resistant B1 and F2 plants with higher chromosome numbers was suggested. The presence of homoeologous pairing observed in all the plants is considered advantageous for selecting suitable progeny in later generations. 相似文献
4.
Somatic hybrids between Sinapis alba (2n= 24) and Brassica oleracea (2n= 18) have been backcrossed with the B. oleracea parent. Whereas backcrosses with the diploid B. oleracea parent were unsuccessful, 344 BC1 seeds could be obtained from inter-valence crosses with tetraploid B. oleracea (2n= 4x= 36). The investigated 96 BC1 plants segregated for morphological traits and for fertility. They were backcrossed with diploid B. oleracea or self-pollinated, depending on their male fertility. The BC1F2 and BC2 progenies segregated well for the morphological traits. Disturbances were observed especially in the generative phase (flower development and pollen fertility). Both male fertile and male sterile BC1F2 and BC2 plants were obtained and backcrossed or self-pollinated with the B. oleracea parent. The presence of either one of the parental or the cybrid organelle genomes was detected. In the progenies, a stable maternal inheritance of the organelle genome patterns was observed. Isozyme analyses revealed polymorphism for the leucine aminopeptidase (LAP) which was used for the identification of S. alba genes in the progenies. Cytological investigations showed a clear differentiation between the BC1F2 and BC2 plants. Whereas the BC1F2 plants possess large numbers of chromosomes ranging from 34 to 40, the BC2 material was strongly reduced to chromosome numbers ranging from 20 to 22. Preliminary investigation of the meiosis suggests the possibility of introgressions of S. alba-DNA into the B. oleracea genome. 相似文献
5.
Summary Interspecific hybridization between Brassica napus L. (2n=38, a1a1c1c1) and B. oleracea var. capitata L. (2x- and 4x-cabbage; 2n=2x=18, cc and 2n=4x=36, cccc) was carried out for the purpose of transferring clubroot disease resistance from the amphidiploid species to cabbage. Nineteen hybrids with three different chromosome levels (2n=28, a1c1c; 2n=37, a1c1cc and 2n=55, a1c1cccc) were obtained. The F1 plants were mostly intermediate between the two parents but as the number of c genomes in the hybrids increased, the more closely the hybrids resembled the cabbage parent. All F1 hybrids were resistant when tested against race 2 of Plasmodiophora brassicae
wor. The complete dominance of resistance over susceptibility suggested that the gene(s) controlling resistance to this particular race of the clubroot pathogen is probably located on a chromosome of the a genome in Brassica.Contribution No. J654. 相似文献
6.
Summary The somatic karyotype and meiotic chromosome behavior were studied in an 18-chromosome B1 plant derived from backcrossing a triploid (Brassica napus x B. oleracea ssp. capitata) F1 hybrid to cabbage. It is considered that cabbage chromosomes no. 1 and no. 7 were substituted by two shorter B. napus chromosomes. Meiotic disturbances were more apparent during the late stages of second division. Seed fertility of this plant was largely restored in the second backcrosses with both cabbage and broccoli. 18-chromosome B2 plants resistant to race 2 of Plasmodiophora brassicae were recovered among the progenies.Contribution no. J. 725 from the Research Station, Research Branch, Agriculture Canada, St-Jean, Québec J3B 6Z8. 相似文献
7.
Summary Genetics of rust resistance against stem rust race 122 in Chhoti Lerma was studied both by conventional and aneuploid analysis. Observations on F1, F2 and F2 backcross progenies revealed the operation of two recessive genes, controlling resistance in Chhoti Lerma. Monosomic analysis confirmed the operation of two recessive genes conferring resistance to race 122 located on chromosomes 1D and 7D. A minor gene or modifier was also located on chromosome 1B. This was concluded from the fact that F2 of mono's x Chhoti Lerma exhibited skewness in favour of resistant plants. 相似文献
8.
Summary Meiosis in 14 interspecific F1 hybrids with three chromosomal levels (triploid, tetraploid, hexaploid; 2n=28, 37 and 55) between Brassica napus L. and 2x and 4x cabbage (B. oleracea var. capitata L.) was studied. The oleracea genome from B. napus maintained close homology with the c genome of cabbage while the campestris genome of B. napus showed partial homology with the c genome contained in the hybrids. Genotypic influence on chromosome pairing was indicated. Structural chromosome differences and spontaneous chromosome breakage and reunion were suggested as causes for the abnormalities which related to the unbalance of the genotypes. The divergence of the genomes of B. napus and B. oleracea and the need for the qualification of the term secondary association were discussed.Contribution No. J. 673, Research Station, Agriculture Canada, St. Jean, Québec. 相似文献
9.
Summary New types of diploids in Brassica crops were synthesized after three consecutive selfing of aneuploids derived from backcrossing of sesquidiploids (2n=29, AAC) with B. campestris (2n=20, AA). The cytogenetic and morphological characteristics of plants with 2n=22, 24 and 40 in the S3 generation were analyzed in order to establish the extent in which these addition and polyploid lines were stabilized. A high frequency of 11II (79.7%), 12II (84.6%) and 20II (100%), were observed at metaphase I of pollen mother cells in 2n=22, 24 and 40 plants, respectively. The chromosome configuration at methaphase II also indicates that a certain level of stability has been attained cytogenetically. Although pollen stainability was relatively high, the seed set percentage was still low. Variation in morphological characteristics indicate the incorporation of one or more chromosome pairs from the C genome of B. oleracea. Other diagnostic characters such as the formation of determinate inflorescence, branching from the base of the stem, and the shift from self-incompatibility to self-compatibility must have resulted from the interaction between A and C genomes. Thus plants with 2n=22, 24 and 40 have been stabilized to some extent and can be developed into new breeding lines of Brassica. It is suggested that limited pollination could be effective in increasing the seed fertility of these plants. 相似文献
10.
Early-bolting trait and RAPD markers in the specific monosomic addition line of radish carrying the e-chromosome of Brassica oleracea 总被引：1，自引：0，他引：1
The specific monosomic addition line of radish, Raphanus sativus, carrying the e chromosome of Brassica oleracea (2n = 19, e‐type MAL) with the genetic background of the late‐bolting cv.‘Tokinashi’ was produced by successive backcrossing of the original e‐type MAL of radish that showed early bolting in the genetic background of the cv. ‘Shogoin’. The early‐bolting trait specific to the e‐type MAL was constantly expressed in the backcrossed progenies (BC2, BC3 and BC4), whereas the reverted radish‐like plants (2n =18) were gradually converted to bolting as late as ‘Tokinashi’. The added e‐chromosome expressed an epistatic effect against the genome of Japanese radish. Its early‐bolting trait was dominant to the late‐bolting trait of ‘Tokinashi’ which may be under the control of a few genes. Moreover, e‐type specific RAPD markers detected in eight primers were invariably transmitted in the backcrossed progenies by ‘Tokinashi’. From the analysis of the characteristics to the e‐type MAL and e‐type specific RAPD markers, it is suggested that the e‐added chromosome of kale (B. oleracea) was transmitted from generation to generation without any recombination with the radish chromosome. The gene(s) for the early‐bolting trait detected in this study may be useful for breeding work in radish, especially in the tropical areas. 相似文献
11.
Summary Aluminium tolerance of Macedonian durum wheat (Triticum turgidum L. conv. durum (Desf.) MacKey) germplasm was evaluated in nutrient solutions containing 0, 74 or 148 M of total Al. Relative root length (148 M Al/0 Al) of various genotypes ranged from 41 to 72% (from moderately sensitive to moderately tolerant to Al). No genotype with Al tolerance close to that of very tolerant T. aestivum cultivar Atlas-66 was found. Seed Ca concentration was positively (r=0.64, P0.05) and seed Fe concentration negatively (r=–0.71, P0.05) related to the relative root growth. Such a significant correlation was not obtained for seed concentrations of other nutrients or seed protein content.Abbreviations HSD
Tukey's Honestly Significant Difference
- RRL-2
relative root length, in % (74 M total Al/0 M Al)
- RRL-4
relative root length, in % (148 M total Al0 M Al) 相似文献
12.
Embryogenic calli derived from anther cultures of the two-rowed winter barley cultivar Igri were plated on solid L3 medium containing the proline analogue hydroxyproline (Hyp), 10–20 mmol l–1. Exposure to Hyp caused severe degeneration of most of the calli. Hyp resistant calli, distinguishable by their lighter colour and higher growth rate, and control calli not exposed to Hyp were plated on L3 regeneration medium. From 22,500 anthers exposed to Hyp 46 Hyp resistant regenerates were obtained, which were transferred to soil. After cultivation for 5–10 weeks at normal growth conditions they were cold hardened at 2 C under short day conditions together with control regenerates. Frost tolerance assays with segments of fully grown leaves of unhardened and cold hardened plants revealed that Hyp resistant regenerants were significantly more frost tolerant than the control regenerants. Improved frost tolerance was found also in the progenies R1 to R9, and genotypic segregation in the R1 generation in a 1:2:1 ratio was indicated. Increased proline content was observed in the R2 generation and in subsequent generations and was significantly (P 0.001) correlated with increased frost tolerance in the Hyp lines. Comparative studies of R9 progenies from homozygous R2 plants with the wild type Igri under field conditions in winter at three locations in Europe as well as crossing experiments confirmed the heritable improvement of frost tolerance and winter survival, respectively, in the Hyp lines. The results support the hypothesis that proline accumulation in cold acclimated winter barley plants is causally related to the acquisition of frost tolerance. Moreover, the described biotechnological procedure may be applicable in breeding programs for improved winter hardiness and possibly also for other stress tolerances. 相似文献
13.
Summary F1 hybrids between short-day photoperiod- sensitive maiwa bulrush millet, Pennisetum americanum (2n=14), and elephant grass, P. purpureum (2n=28), are triploid (2n=21), sterile, and can only be propagated vegetatively. Fertile amphidiploids, (2n=42, with 21 bivalents) were produced by colchicine treatment. Good seed set was obtained upon selfing the amphidiploids and the progeny exhibited variable pollen fertility and bivalent univalent and multivalent formation.Reciprocal crosses between elephant grass and the colchicine-induced amphidiploid failed to produce seeds. The maiwa millet x amphidiploid cross resulted in poor seed set and the reciprocal failed. Maiwa x amphidiploid hybrids were pollen sterile with 2n=21, rather than the expected 2n=28, indicating chromosome elimination.Morphologically, the amphidiploids and maiwa x amphidiploid hybrids closely resembled elephant grass and the F1 hybrid. The amphidiploids showed no superiority over the F1 hybrid and elephant grass in either forage yield or quality but one maiwa x amphidiploid genotype surpassed a promising local elephant grass selection in forage dry matter yield and flowered for a relatively short period. 相似文献
14.
S. W. Bang K. Sugihara B. H. Jeung R. Kaneko E. Satake Y. Kaneko Y. Matsuzawa 《Plant Breeding》2007,126(1):101-103
Intergeneric crosses were made between Brassica oleracea and Moricandia arvensis utilizing embryo rescue. Six F1 hybrid plants were generated in the cross‐combination of B. oleracea × M. arvensis from 64 pods by the placenta‐embryo culture technique, whereas three plants were produced in the reciprocal cross from 40 pods by the ovary culture technique. The hybrid plants were ascertained to be amphihaploid with 2n = 23 chromosomes in mitosis and a meiotic chromosome association of (0–3)II + (17–23)I at metaphase I (M I). In the backcross with B. oleracea, some of these hybrids developed sesquidiploid BC1 plants with 2n = 32 chromosomes that predominantly exhibited a meiotic configuration of (9II + 14I) in pollen mother cells. The following backcross of BC2 plants to B. oleracea generated 48 BC3 progeny with somatic chromosomes from 2n = 19 to 2n = 41. The 2n = 19 plants showed a chromosomal association type of (9II + 1I) and a chromosomal distribution type of (91/2 + 91/2) or (9 + 10) at M I and M II, respectively. These facts might suggest that they were monosomic addition lines (MALs) of B. oleracea carrying a single chromosome of M. arvensis that could offer potential for future genetic and breeding research, together with other novel hybrid progeny developed in this intergeneric hybridization. 相似文献
15.
Synthesis and sterility of raphanobrassica 总被引：4，自引：0，他引：4
I. H. McNaughton 《Euphytica》1973,22(1):70-88
Summary The synthesis of Raphanobrassica (2n=36, rrcc) from Raphanus sativus (2n=18, rr) and Brassica oleracea (2n=18, cc) is described a) by colchicine treatment of diploid hybrids; b) by crossing autotetraploid froms of the parent species.The variation within R. sativus and B. oleracea suggests that a range of morphologically distinct Raphanobrassica forms may be created, some of which may have agronomic potential and in particular, it is hoped, Plasmodiophora resistance.Inter-generic hybrids were readily obtained from crossing the parental species at both 2x and 4x chromosome levels, but only with R. sativus as female parent.Details are given of the morphology, fertility and chromosome behaviour of both diploid F1
R. sativus × B. oleracea hybrids and of the amphidiploid Raphanobrassica.Synthesized Raphanobrassica plants proved, in general, highly sterile. Some aneuploids resulted from 4x R. sativus × 4x B. oleracea crosses but most progeny were euploid and showed almost regular chromosome association. A number of stunted, deformed plants were obtained from both 2x and 4x crosses. Vigour, fertility and aneuploidy appeared unconnected in the amphidiploid.Previous work on Raphanobrassica is reviewed. It is concluded that the extremely low fertility encountered in the present study is more likely to be the result of genic imbalance than to cytological anomalies which appear to be of lesser significance. 相似文献
16.
Interspecific hybrids were produced from reciprocal crosses between Brassica napus (2n = 38, AACC) and B. oleracea var. alboglabra (2n = 18, CC) to introgress the zero-erucic acid alleles from B. napus into B. oleracea. The ovule culture embryo rescue technique was applied for production of F1 plants. The effects of silique age, as measured by days after pollination (DAP), and growth condition (temperature) on the
efficiency of this technique was investigated. The greatest numbers of hybrids per pollination were produced under 20°/15°C
(day/night) at 16 DAP for B. oleracea (♀) × B. napus crosses, while under 15°/10°C at 14 DAP for B. napus (♀) × B. oleracea crosses. Application of the ovule culture technique also increased the efficiency of BC1 (F1 × B. oleracea) hybrid production by 10-fold over in vivo seed set. The segregation of erucic acid alleles in the self-pollinated backcross
generation, i.e. in BC1S1 seeds, revealed that the gametes of the F1 and BC1 plants carrying a greater number of A-genome chromosomes were more viable. This resulted in a significantly greater number
of intermediate and a smaller number of high-erucic acid BC1S1 seeds. 相似文献
17.
Yoshio Yoshida 《Euphytica》1964,13(1):65-74
If the expectation of the number of desirable mutants for equal size of X
2-populations decreases with decreasing number of plants per X
2-line, the one-plant-one-grain method (method C), the one-plant-two-grain method (method D), and the one-plant-three-grain method (method E), especially method C, would be disadvantageous in comparison with the improved ear-to-row method (method B) and the conventional ear-to-row method (method A).From theoretical considerations it can be shown that a probability of occurrence of an X
2-line containing desirable mutant (p
1) and a conditional probability of occurrence of such desirable mutant for each one of the plants in such an X
2-line (p
2) are not affected by the number of X
2-lines (m), but by the number of plants per X
2-line (n). Consequently, the expectation of the number of desirable mutants in an X
2-population, E(I), can be given by
E(I) = mp
1(1– q
2
n · n p
2/(1 –q
2
n) = mn p
1
p
2
where p
1+q
1=1 and p
2+q
2=1.Therefore, with respect to E(I), method A=B=C=D=E for equal size of X
2-populations. However, method ABE>D>C for different sizes of X
2-populations.Most of this work was carried out in the National Institute of Agricultural Sciences, Hiratsuka, Japan. 相似文献
18.
G. R. Mackay 《Euphytica》1977,26(2):511-519
Summary Forage rape. B. napus, is self-compatible, the work described illustrates the introgression of functional incompatibility alleles into B. napus from turnips, B. campestris, in two generations. By grading seed, produced by backcrossing turnip/rape hybrids to rape, the frequency of 2n=38 semi articial B. napus recovered, amply justifies the cytological screening involved in such breeding programmes. 相似文献
19.
E. C. Thörn 《Euphytica》1992,59(2-3):109-118
Summary Seed and embryo development was studied in crosses between H. bulbosum and the barley genotypes VK 16032, Vada and Vogelsanger Gold and subsequently the F1 and F2 progenies from VK 16032 x Vada and VK 16032 x Vogelsanger Gold. Both seed and embryo development are strongly influenced by the barley genotype. Favourable environmental conditions can promote seed and embryo development in genotypes with existing good characters. Dominant inheritance for good seed development and incomplete dominance for large embryos is evident. Linkage between small embryo size and winter habit exists in Vogelsanger Gold. 相似文献
20.
Broadening the genetic base of the C genome of Brassica napus canola by use of B. oleracea is important. In this study, the prospect of developing B. napus canola lines from B. napus?×?B. oleracea var. alboglabra, botrytis, italica and capitata crosses and the effect of backcrossing the F1’s to B. napus were investigated. The efficiency of the production of the F1’s varied depending on the B. oleracea variant used in the cross. Fertility of the F1 plants was low—produced, on average, about 0.7 F2 seeds per self-pollination and similar number of BC1 seeds on backcrossing to B. napus. The F3 population showed greater fertility than the BC1F2; however, this difference diminished with the advancement of generation. The advanced generation populations, whether derived from F2 or BC1, showed similar fertility and produced similar size silique with similar number of seeds per silique. Progeny of all F1’s and BC1’s stabilized into B. napus, although B. oleracea plant was expected, especially in the progeny of F1 (ACC) owing to elimination of the A chromosomes during meiosis. Segregation distortion for erucic acid alleles occurred in both F2 and BC1 resulting significantly fewer zero-erucic plants than expected; however, plants with?≤?15% erucic acid frequently yielded zero-erucic progeny. No consistent correlation between parent and progeny generation was found for seed glucosinolate content; however, selection for this trait was effective and B. napus canola lines were obtained from all crosses. Silique length showed positive correlation with seed set; the advanced generation populations, whether derived from F2 or BC1, were similar for these traits. SSR marker analysis showed that genetically diverse canola lines can be developed by using different variants of B. oleracea in B. napus?×?B. oleracea interspecific crosses. 相似文献