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1.
Summary Nucleus substitution of Brassica japonica (2n=20) with Raphanus sativus (2n=18) was carried out by means of repeated backcrossing of Brassicoraphavus (2n=37) to R. sativus as a pollen donor. In the course of nucleus substitution, chlorophyll deficiency appeared. Plants with more than 28 chromosomes, like their parents, had green leaves and those with 24 to 26 chromosomes had yellowish green ones. Almost all plants with 18 to 23 chromosomes showed yellow or whitish yellow. The R. sativus with B. japonica cytoplasm (2n=18) was obtained after four successive backerosses. The completely substituted R. sativus showed the same fertility as the true R. sativus used as a recurrent parent. It is assumed that the chlorophyll deficiency is caused by disharmony between the B. japonica cytoplasm and the R. sativus nucleus. The chlorophyll deficiency is discussed in comparison with male sterility or other characters which sometimes occur in alloplasmic Raphanus and Brassica species. 相似文献
2.
N. Arumugam A. Mukhopadhyay V. Gupta Y. S. Sodhi J. K. Verma D. Pental A. K. Pradhan 《Plant Breeding》2002,121(2):168-170
Brassica carinata (BBCC), a potential oilseed crop for dry land agriculture, is sensitive to high temperatures during germination and early stages of growth, which thereby restricts the possibility of using the residual soil moisture available after the rainy season for its cultivation. To overcome this problem, a three‐genome hybrid, RCBB, was synthesized using Raphanus sativus (RR) and Brassica oleracea (CC) as donor sources for the desired heat tolerance. Protoplasts of RC hybrids obtained through sexual crosses between R. sativus (female) and B. oleracea (male) were fused with protoplasts of Brassica nigra (BB) to produce RCBB somatic hybrids. The hybrid colonies regenerated with an average frequency of 7.6%. Twelve out of 36 hybrids grown to maturity were characterized for their nuclear and organelle genomes. While all the hybrids showed the presence of B. nigra chloroplasts, 10 of the hybrids showed B. nigra‐specific mitochondria and two had Raphanus‐spedfic mitochondria. The somatic hybrids could be backcrossed to B. carinata. 相似文献
3.
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
4.
Cytogenetical and molecular investigations on somatic hybrids of Sinapis alba and Brassica juncea and their backcross progeny 总被引：3，自引：0，他引：3
Somatic hybrids of Sinapis alba+Brassica juncea (Sal Sal AABB) were synthesized by protoplast electrofusion. They were true genomic allopolyploids since they possessed 60 chromosomes, i.e. the sum of S. alba (2n= 24) and B. juncea (2n= 36) chromosomes. Chromosome pairing was predominantly bivalent with the occasional occurrence of multivalents in the pollen mother cells at diakinesis and metaphase I. Hybrids were completely pollen-sterile, but produced seeds on back-crossing with B. juncea and B. campestris. A total of 37 BC1 plants were raised from two somatic hybrids (JS-1 and JS-2) and 24 of these were analysed cytologically. The 22 plants originating from the pollinations of somatic hybrids with B. juncea showed a chromosome configuration of 18II+12I and had 42–86% pollen fertility. Two plants from the backcrosses of the somatic hybrid with B. campestris formed 10II +20I, and had 0–4% fertile pollen. Total DNA analysis by probing with pTA71 carrying a full-length 18S–25S rDNA fragment of the wheat nuclear genome revealed that the two somatic hybrids possessed all the characteristic bands of both the species, confirming their hybridity. Probing with the mitochondrial coxI and atp9 genes indicated mitochondrial genome recombination in the hybrids. Hybridization with chloroplast-specific psbD indicated that both the somatic hybrids possessed the cp genome of S. alba origin. 相似文献
5.
Assessment of genetic relationships among Cucumis spp. by SSR and RAPD marker analysis 总被引：1，自引：0，他引：1
The first successful production of a sterile interspecific hybrid obtained from a cross between Cucumis hystrix Chakr. (2n = 2x = 24) and Cucumis sativus var. sativus L. (2n =2x = 14), and its subsequent fertility restoration through chromosome doubling provide an effective means for investigating genetic relationships among Cucumis spp. In this study, random amplified polymorphic DNA (RAPD) and simple sequence repeat (SSR) markers were used to investigate relationships among C. s. var. sativus L., C. s. var. hardwickii (R.) Alef., C hystrix, C. hytivus Chen & Kirkbride (the amphidiploid species from chromosome doubling of the C. sativus x C. hystrix interspecific hybrid, 2n = 38), C. melo (2n =2x = 24) and C. metuliferus Meyer and Naudin (2n =2x= 24). A total of 109 SSR bands and 398 RAPD primed sites were used to calculate Jaccard's distance coefficients for cluster analysis using a unweighted pair‐group method using an arithmetic averaging (UPGMA) algorithm. The genetic relationships identified using SSR and RAPD markers were highly concordant, such that the correlation between SSR and RAPD genetic distance (GD) estimates was r = 0.94. SSR and RAPD analysis of 22 accessions allowed for their grouping into two distinct groups designated as CS and CM. While group CS consisted of 11 C. sativus genotypes, and the C. hytivus and C. hystrix accessions, group CM included six C. melo genotypes and C. metuliferus. The GD values between C. hystrix and C. sativus ascribed by SSR and RAPD matrices were 0.59 and 0.57, respectively. These GDs were smaller than those detected between C. hystrix and C melo (0.87 and 0.70 derived from SSR and RAPD markers, respectively). 相似文献
6.
Homoeological relationships between the f chromosome of Brassica rapa and the e chromosome of Brassica oleracea 总被引：1，自引：0，他引：1
Eight plants of the putative double monosomic addition line (DMAL, 2n= 20) were developed by crossing a monosomic chromosome addition line of radish [f(A)‐type monosomic addition line (MAL) (2n= 19)] carrying the f chromosome of Brassica rapa (2n= 20, AA) with another [e(C)‐type MAL (2n= 19)] having the echromosome of Brassica oleracea (2n= 18, CC). The homoeological relationships between the two alien chromosomes were investigated by morphological, cytogenetic and random amplified polymorphic DNA (RAPD) analysis. Seventeen morphological traits that were not present in the radish cv. ‘Shogoin’ were observed in both MALs and these traits were substantially exhibited in DMAL plants. At the first metaphase of pollen mother cells (PMCs), the two parental MALs showed a chromosome configuration of 9II +1I, demonstrating impossibility of recombination between the R and the added chromosomes. The DMALs formed 10II in approximately 73% of PMCs, with one bivalent showing loose pairing between two chromosomes differing in size. In an attempt to identify the two MALs by RAPD‐specific markers using 26 selected random primers, 13 and 20 bands were specific for the f(A)‐type and the e(C)‐type MALs, respectively; 12 bands were common to both MALs (26.7%). In conclusion, the f chromosome of B. rapa is homoeologous to the e chromosome of B. oleracea. The genetic domain (genes) for 17 morphological traits are linked to each homoeologous chromosome bearing 27% of the corresponding RAPD markers. 相似文献
7.
Interspecific hybridization plays a crucial role in plant genetics and breeding. The efficiency of interspecific crosses to
a considerable extent depends on the genetic relatedness of genomes from parental species. Interspecific hybrids involving
Brassica maurorum (2n = 16, MM) and two Brassica crop species, viz B. rapa (2n = 20, AA) and B. napus (2n = 38, AACC), were produced and analyzed for their meiotic chromosome pairings in pollen mother cells (PMCs) by using genomic
in situ hybridization (GISH) with the labeled DNA of B. maurorum (MM) as probe. In hybrids B. maurorum × B. rapa (2n = 18, MA), all chromosomes remained unpaired in 28% PMCs, and the maximum of autosyndetic bivalents was two and one among
the chromosomes of A and M genomes, with the average per cell being 0.27 and 0.12, respectively. Up to two allosyndetic bivalents
between A and M genomes appeared, averagely 0.48 per cell. In hybrids B. maurorum × B. napus (2n = 27, MAC), the maximum of autosyndetic bivalents in M genome was two and the average was 0.11, while the maximum of allosyndetic
bivalents between M and A/C genomes was two and the average was 0.78. The 2–7 bivalents formed by A/C-genome chromosomes showed
their high homology. The results were compared and discussed with the chromosome pairings in the hybrids of B. maurorum with B. juncea and B. carinata with respect to the genome relationships and the potential for chromosome recombination. 相似文献
8.
The effect of genome composition and cytoplasm on petal size was studied in Brassica. Two accessions of Brassica rapa (2n = 20, AA) were reciprocally crossed with three accessions of Brassica oleracea (2n =18, CC) to produce resynthesized B. napus (2n = 38, AACC or CCAA) and sesquidiploids (2n = 29, AAC or CAA). Petal size was measured and compared among diploids (AA and CC), sesquidiploids (AAC and CAA) and amphidiploids(AACC and CCAA). The results showed that petal size is a genome‐dependent and highly heritable character. The heritability of petal length is as high as 96.3%. The addition of each C‐genome to the AA genomic background increased the petal length by 4‐5 mm. Cytoplasm of B. oleracea showed a positive effect on petal length by about 1.3 mm over that of B. rapa. Petal width was positively correlated with petal length at a highly significant level (r= 0.806, df = 81). Resynthesized B. napus (AACC) showed significantly larger flower petals than natural rapeseed cultivars (AACC). 相似文献
9.
M. H. Rahman 《Plant Breeding》2002,121(4):357-359
The fatty acid composition of seed oil of four interspecific hybrids, resulting from crosses between zero erucic acid Brassica rapa (AA), and high erucic acid Brassica alboglabra/Brassica oleracea (CC) and Brassica carinata (BBCC), void of erucic acid genes in their A‐genomes was examined. The erucic acid content in resynthesized Brassica napus (AACC) lines derived from these crosses was only about half that of the high erucic acid CC genome parents, indicating equal contributions of the two genomes to oil (fatty acid) synthesis and accumulation. The differences in C18 fatty acid synthesis between the parents were also evident in the resulting resynthesized B. napus plants. Hexaploid Brassica plants of the genomic constitution AABBCC, in which the AA genome was incapable of erucic acid synthesis, had lower erucic acid contents than the B. carinata (BBCC) parent. This is plausible considering the fact that the zero erucic acid AA genome contributes to oil synthesis in AABBCC plants, thus reducing erucic acid content. 相似文献
10.
In order to introgress the ‘glandless-seed and glanded-plant’ trait from Gossypium sturtianum Willis (2n= 2x= 26, C1 genome) into the cultivated upland cotton Gossypium hirsutum L. (2n= Ax= 52 (AD), genome), two trispecific hybrids have been created using either Gossypium thurberi Torado (2n= 2x= 26, D1 genome) or Gossypium raimondii Ulbrich (2n= 2x= 26, D5 genome) as bridge species. The cross of both trispecific hybrids by G. hirsutum produced the first backcross progenies (BCl). Cytogenetic analysis showed that the trispecific hybrids had 52 chromosomes, their chromosome configurations at metaphase I (Ml) being 15.071 + 15.3411 + 0.93III + 0.69IV + 0.26VI in G. thurberi×G. sturtianum×G. hirsutum (TSH) and 14.421 + 17.0311 + 0.82III + 0.15IV + 0.07VI in G. hirsutum × G. raimondii ×. G. sturtianum (HRS), respectively. Among six BCl plants analysed, the only plant expressing the ‘glandless-seed and glanded-plant’ trait had 52 chromosomes and a meiotic configuration of 5.261 + 20.61II + 0.69III + 0.77IV at MI. Pollen fertility was 2.90% in TSH, 8.97% in HRS, and ranged from 0% to 40.28% in the BCl progenies. The introgressed BCl plant is perennial in growth habit. It can be used in breeding programmes aiming at the introgression of the ‘glandless-seed and glanded-plant’ trait into a cultivar of upland cotton. 相似文献
11.
Jing Wen Xin-hua Zeng Yuan-yuan Pu Li-ping Qi Zai-yun Li Jin-xing Tu Chao-zhi Ma Jin-xiong Shen Ting-dong Fu 《Euphytica》2010,173(1):99-111
Meiotic nondisjunction during microsporegenesis can lead to aneuploid gametes formation and reduced pollen fertility in plants.
This paper reports the prevalence of meiosis I nondisjunction in a resynthesized Brassica napus (AACC, 2n = 38) and its use for aneuploid production. Meiosis in the amphidiploids was characterized by high frequencies of univalents
and multivalents per PMC at diakinesis/metaphase I and notably unbalanced chromosome segregations at anaphase I (AI). In all
the plants observed, 18.95–44.3% of PMCs exhibited a segregation of 18:20 (n − 1:n + 1) at AI which was caused by nondisjunction of one bivalent or the distribution of two homologous univalents to the same
pole. Meiosis proceeded normally after AI then, thus led to the formation of viable n − 1 and n + 1 gametes and high pollen fertility of these plants. Microspore culture was subsequently carried out using these plants
in an attempt to isolate Brassica nullisomics. Four nullisomics (2n = 36), two nullihaploids (2n = 18) and one tetrasomic haploid (2n = 20) were identified cytologically and characterized morphologicaly and physiologically. Amplified fragment length polymorphism
(AFLP) survey suggested that of the six nullisomics/nullihaploids, one nullihaploids lost one A-genome chromosome and the
other five lost C genome chromosome(s). Altogether, different C-genome chromosomes were thought to have been lost in the nullisomics/nullihaploids.
The mechanisms underlying the meiotic abnormalities and the implications of these B. napus nullisomics are discussed. 相似文献
12.
The effect of genome composition and cytoplasm on petal colour was studied in Brassica. Three accessions of yellow‐petalled B. rapa (2n= 20, AA) were crossed with a white‐petalled B. oleracea var. alboglabra (2n= 18, CC) and with three cream‐yellow‐petalled B. oleracea var. gongylodes (2n= 18, CC) to produce resynthesized B. napus (2n= 38, AACC or CCAA) and sesquidiploids (2n= 29, AAC or CAA). Petal colour was measured with a Hunter automatic colour difference meter. The results revealed that petal colour in Brassica is controlled by nuclear genes and by cytoplasmic factors. Additive and epistatic gene effects were involved in the action of nuclear genes. When crosses were made between yellow‐petalled B. rapa and white‐petalled B. oleracea var. alboglabra, significant additive, epistatic and cytoplasmic effects were found. White petal colour was partially epistatic over yellow petal colour. When crosses were made between yellow‐petalled B. rapa and cream‐yellow‐petalled B. oleracea var. gongylodes, only epistatic effects were detected. Yellow petal colour was epistatic over cream‐yellow. 相似文献
13.
Intergeneric crosses for the transfer of resistance to the beet cyst nematode from Raphanus sativus to Brassica napus 总被引：10，自引：0，他引：10
Summary The possibilities to transfer important traits and in particular resistance to the beet cyst nematode (Heterodera schachtii, abbrev. BCN) from Raphanus sativus to Brassica napus were investigated. For these studies B. napus, R. sativus, the bridging hybrid ×Brassicoraphanus (Raparadish) as well as offspring of the cross ×Brassicoraphanus (Raparadish) ×B. napus were used. Reciprocal crosses between B. napus and R. sativus were unsuccessful, also with the use of embryo rescue. Crosses between ×Brassicoraphanus as female parent and B. napus resulted in a large number of F1 hybrids, whereas the reciprocal cross yielded mainly matromorphic plants. BC1, BC2 and BC3 plants were obtained from backcrosses with B. napus, which was used as the male parent. F1 hybrids and BC plants showed a large variation for morphology and male and female fertility. Cuttings of some F1 and BC1 plants, obtained from crosses involving resistant plants of ×Brassicoraphanus, were found to possess a level of resistance similar to that of the resistant parent. These results and indications for meiotic pairing between chromosomes of genome R with those of the genomes A and/or C suggest that introgression of the BCN-resistance of Raphanus into B. napus may be achieved. 相似文献
14.
S. Prakash I. Ahuja H. C. Upreti V. Dinesh Kumar S. R. Bhat P. B. Kirti V. L. Chopra 《Plant Breeding》2001,120(6):479-482
An alloplasmic mustard, Brassica juncea, has been synthesized by placing its nucleus into the cytoplasm of the related wild species Erucastrum canariense to express cytoplasmic male sterility. To achieve this, the sexual hybrid E. canariense (2n=18, EcEc) ×Brassica campestris (2n= 20, AA) was repeatedly backcrossed to B. juncea (2n= 36, AABB). Cytoplasmic male‐sterile (CMS) plants were recovered in the BC4 generation. These plants are a normal green and the flowers have slender, non‐dehiscing anthers that contain sterile pollen. Nectaries are well developed and female fertility is > 90%. The fertility restoration gene was introgressed to CMS B. juncea from the cytoplasmic donor E. canariense through pairing between chromosomes belonging to B. juncea with those of the E. canariense genome. The restorer plants have normal flowers, with well‐developed anthers containing fertile pollen. Meiosis proceeds normally. Pollen and seed fertility averaged 90% and 82%, respectively. F1 hybrids between CMS and the restorer are fully pollen fertile and show normal seed set. Preliminary results indicate that restoration is achieved by a single dominant gene. The constitution of the organelle genomes of the CMS, restorer and fertility restored plants is identical, as revealed by Southern analysis using mitochondrial and chloroplast probes atp A and psb D, respectively. 相似文献
15.
Production and characterization of intergeneric somatic hybrids between Moricandia arvensis and Brassica oleracea 总被引：3，自引：0，他引：3
Somatic hybrids were produced between Moricandia arvensis (MaMa, 2n= 28) and Brassica oleracea (CC, 2n= 18) through cell fusion and then characterized by analysing their morphology, cytology, DNA constitution, leaf anatomy and seed fertility. Cell fusion was carried out between greenish protoplasts isolated from the mesophyll of M. arvensis and colourless ones from hypocotyls of B. oleracea. Three plants were generated from one shoot via cuttings and acclimatized in vivo. They closely resembled each other in morphology, exhibiting traits intermediate between the parental species. They were confirmed to be amphidiploids by mitotic and meiotic analyses, being 2n= 46 (MaMaCC), with pollen fertility of about 50%, which was enough to develop the subsequent progenies. Anatomical analysis of the for leaf tissue showed that the bundle sheath cells of the somatic hybrids contained some centripetally arranged organelles, like those of M. arvensis. The hybridity was also confirmed by random amplified polymorphic DNA analysis. Both chloroplast DNA and mitochondrial DNA of the somatic hybrids were estimated to be derived from M. arvensis. In leaf anatomy, the somatic hybrid showed the C3‐C4 intermediate trait as in M. arvensis. Many progenies resulted from backcrossing with parental species. The somatic hybrids are expected to be used as bridging plant material to introduce the C3‐C4 intermediate trait into Brassica crop species. 相似文献
16.
A synthetic amphidiploid species Cucumis hyriviis Chen & Kirkbride (2n = 4x = 38; genome designated as HHCC) has recently been created from an interspecific mating between C. sativus L. (2n = 2x = 14: genome designated as CC) and C. hystrx. Chakr. (2n = 2x = 24; genome designated as HH). This amphidiploid is resistant to root knot nematode, tolerant to low irradiance, and has higher nutritional value than standard processing cucumber cultivars. An allotriploid (2n = 3x = 26; HCC) was derived from a cross between C. sativus L. and C. hytivus Chen & Kirkbride. Diploid meiotic behaviour in C. sativus and C. hystrix involves the development of seven and 12 metaphase bivalents respectively. In the derived allotriploid. univalents. bivalents, and trivalents (at relatively low frequency) were observed at metaphase I indicating that some homeologues from the C and H genomes can synapse. Based on a comparative karyotype analysis of cucumber (i.e. chromosome size and pairing behaviour) and aliotriploid plants, the seven bivalents observed at metaphase I were ascertained to be cucumber homologues, while the 12 univalents were of C. hystrix origin thus confirming the allotriploid karyotypic constitution to be HCC. On average, the frequency of trivalents was 0.24 at diakinesis and 0.22 in 100 meiocytes at metaphase I. indicating the possibility of genetic exchange due to the homoeology between the C and H genomes. After simultaneous cytokinesis, only polyads were observed in pollen mother cells (PMCs) at telophase II, which led to the production of sterile pollen grains. Multi‐polarization of chromosomes was dominant at anaphase II. However. in about 20% PMCs. chromosomes separated to form a 7C + 1‐2H complement, suggesting a possible method for the production of alien addition cucumber‐C hystrix lines through further backcrossing of the allotriploid to diploid cucumber. 相似文献
17.
Incompatibility in diploid and tetraploid crosses of Cucumis sativus and Cucumis metuliferus 总被引：1，自引：0，他引：1
The African horned cucumber (Cucumis metuliferus Naud.; 2x = 2n = 24) contains genes that can confer resistance to many important cucumber (C. sativus L.; 2x = 2n = 14) pests [e.g., root-knotnematode, Meloidogyne incognita (Kofoid & White) Chitwood]. Cucumber is highly susceptible to this root-knot nematode species, and a recent screening of
C. sativus accessions in the U.S. National Plant Germplasm collection did not identify sources of resistance. Thus,autotetraploids of
Cucumis sativus and C. metuliferus were created to recover fertile resistant interspecific progeny. Autotetraploids were obtained at the highest rate when seeds
were immersed in 0.5% colchicine for a period of 6 to 8 hrs. Treatment durations less than 6 hrs produced few tetraploids,
and durations of 10 hrs or more were lethal to seeds or developing seedlings. Crosses between C. sativus and C. metuliferus were made using diploid and tetraploid lines in all possible combinations, including reciprocals. Fruit development occurred
in crosses when diploid and tetraploid C. sativus were used as the female parent. However, seeds developed only in fruit of C. sativus (4n) ×C. metuliferus (2n) crossings. Seeds from these crosses, however,were flat and not viable. No fruit development occurred in crosses whereC. metuliferus was used as the female parent.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
18.
A. D. Munshi Bishwajit Panda Bikash Mandal I. S. Bisht E. S. Rao Ravinder Kumar 《Euphytica》2008,164(2):501-507
The genetics of resistance to Cucumber mosaic virus (CMV) in Cucumis sativus var. hardwickii R. Alef, the wild progenitor of cultivated cucumber was assessed by challenge inoculation and by natural infection of CMV.
Among the 31 genotypes of C. sativus var. hardwickii collected from 21 locations in India the lowest mean percent disease intensity (PDI) was recorded in IC-277048 (6.33%) while
the highest PDI was observed in IC-331631 (75.33%). All the four cultivated varieties (DC-1, DC-2, CHC-1 and CHC-2) showed
very high PDI and susceptible disease reaction. Based on mean PDI, 8 genotypes were categorized as resistant, 13 as moderately
resistant, 9 as moderately susceptible and one as susceptible. A chi-square test of frequency distribution based on mean PDI
in F2 progenies of six resistant × susceptible crosses revealed monogenic recessive Mendelian ratio 1(R):3(S) to be the best fit.
This monogenic recessive model was further confirmed by 1(R):1(S) ratio as the best fit for back cross with resistant parent
and no fit for either 3:1 or 1:1 in the back cross with the susceptible parent. The results revealed that CMV resistance in
C. sativus var. hardwickii was controlled by a single recessive gene. Considering the cross compatibility between C. sativus var. hardwickii and cultivated cucumber, the resistance trait can be easily transferred to cultivated species through simple backcross breeding. 相似文献
19.
W. H. Wei S. F. Zhang L. J. Wang J. LI B. Chen Z. Wang L. X. Luo X. P. Fang 《Plant Breeding》2007,126(4):392-398
By intergeneric sexual hybridization between Sinapis alba and Brassica oleracea , F1 , F2 and BC1 progeny plants were produced. S. alba plants (genome SS, 2n = 24) were pollinated with B. oleracea (genome CC, 2n = 18), and the fertile F1 plants were pollinated with B. oleracea to obtain BC1 plants. GISH analysis showed that 10 out of 12 F1 plants had 12 S. alba chromosomes (one full S chromosome set) and nine B. oleracea chromosomes (one C chromosome sets), representing the expected hybrids. However, two F1 plants had 12 S chromosomes and 18 C chromosomes (two C chromosome sets), indicating unexpected hybrids. A maximum of three trivalents between C and S chromosomes were identified at metaphase I of semi-fertile F1 pollen mother cells (PMCs), which indicates homology and chromosome pairing between these two genomes. The C genome had obviously been doubled in two F2 plants from selfed semi-fertile F1 plants. BC1 plants consisted of 18 C chromosomes and different numbers of one, five and six additional S chromosomes, respectively. Monosomic alien addition lines developed in the present study can be used for B. oleracea breeding and Sinapis alba gene mapping. 相似文献
20.
Hanne Denaeghel Katrijn Van Laere Leen Leus Johan Van Huylenbroeck Marie-Christine Van Labeke 《Euphytica》2017,213(7):149
Knowledge of ploidy level differences, genome size and genetic relationships between species facilitates interspecific hybridization in ornamentals. For Sarcococca (Buxaceae) only limited (cyto)genetic information is available. The aim of this study was to determine the genome size and chromosome number and to unravel the genetic relationships of a breeder’s collection using AFLP marker analysis. Based on these results, interspecific crosses were made and the efficiency and hybrid status was verified. Two groups of diploid plants (2n = 2x = 24) were observed, with either a genome size of 4.11–4.20 or 7.25–9.63 pg/2C. All the tetraploid genotypes (2n = 4x = 48) had genome sizes ranging from 7.91 to 8.18 pg/2C. In crosses between parents with equal ploidy level and genome size a higher crossing efficiency (on average 58% of the hybridizations resulting in fruits) and more true hybrids (on average 96% of the offspring) were obtained compared to crosses between plants with different genome size and ploidy level (on average 23% fruits and 24% hybrids, respectively). In none of the cross combinations, the ploidy level or genome size was found to be a complete hybridization barrier, although unilateral incongruity was found in some cross combinations. Distant genetic relationships did not hamper the hybridization within Sarcococca genotypes. Our findings will contribute to a more efficient breeding program and a faster achievement of hybrids with an added value. 相似文献