Haynaldia villosa possesses a lot of important agronomic traits and has been a powerful gene resource for wheat improvement. However, only several wheat-H, villosa translocation lines have been reported so far. In thi...Haynaldia villosa possesses a lot of important agronomic traits and has been a powerful gene resource for wheat improvement. However, only several wheat-H, villosa translocation lines have been reported so far. In this study, we attempted to develop an efficient method for inducing wheat-H, villosa chromosomal translocations. Triticum durum- Haynaldia villosa amphiploid pollen treated with 1 200 rad ^60Co-y-rays was pollinated to Triticum aestivum cv. ＇Chinese Spring＇. Ninety-eight intergeneric translocated chromosomes between T. durum and H. villosa were detected by genomic in situ hybridization in 44 of 61 M1 plants, indicating a translocation occurrence frequency of 72.1%; much higher than ever reported. There were 26, 62 and 10 translocated chromosomes involving whole arm translocations, terminal translocations, and intercarlary translocations, respectively. Of the total 108 breakage-fusion events, 79 involved interstitial regions and 29 involved centric regions. The ratio of small segment terminal translocations （W.W-V） was much higher than that of large segment terminal translocations （W-V.V）. All of the M1 plants were self-sterile, and their backcross progeny was all obtained with ＇Chinese Spring＇ as pollen donors. Transmission analysis showed that most of the translocations were transmittable. This study provides a new strategy for rapid mass production of wheat-alien chromosomal translocations, especially terminal translocations that will be more significant for wheat improvement.展开更多
: Electrically induced protoplast fusion was used to produce somatic hybrids between Brassica napus L. and Sinapis alba L. Seven hybrids were obtained and verified by the simple sequence repeat and cleaved amplified p...: Electrically induced protoplast fusion was used to produce somatic hybrids between Brassica napus L. and Sinapis alba L. Seven hybrids were obtained and verified by the simple sequence repeat and cleaved amplified polymorphic sequence analysis of the gene fael, indicating that the characteristic bands from S. alba were present in the hybrids. The hybridity was also confirmed by chromosome number counting because the hybrids possessed 62 chromosomes, corresponding to the sum of fusion-parent chromosomes. Chromosome pairing at meiosis was predominantly normal, which led to high pollen fertility, ranging from 66% to 77%. All hybrids were grown to full maturity and could be fertilized and set seed after self-pollination or back-crosses with B. napus. The morphology of the hybrids resembled characteristics from both parental species. An analysis of the fatty acid composition in the seeds of F1 plants was conducted and the seeds were found to contain different amounts of erucic acid, ranging from 11.0% to 52.1%.展开更多
The intergeneric hybridization between Brassica napus L. cv. oro and Matthiola incana (L.) R. Br. was carried out to study the phytogenetic peculiarities of the hybrid plants. In order to improve the oil quality of ra...The intergeneric hybridization between Brassica napus L. cv. oro and Matthiola incana (L.) R. Br. was carried out to study the phytogenetic peculiarities of the hybrid plants. In order to improve the oil quality of rape seed, ovaries of B. napus pollinated with pollen of M. incana, were cut off and inoculated onto MS media supplemented with various plant hormones at the 7th day after pollination. Two mature embryos were obtained from 750 pollinated ovaries cultured in vitro. The percentage of seed set was 0.26%. The mature embryos were transferred onto the MS media supplemented with 2.0 mg/L 6-BA + 0.1 mg/L NAA, and a compound bud was produced later. The compound bud was then cut into a number of single buds, which were transferred onto fresh media. Twenty-two plantlets in vitro were developed from the above single buds. The hybrid plants (F-1) were basically intermediate between the two parents in many,characters with a few showing hybrid vigor. The fertility of hybrid plants (F-1) was poor. Cytological studies revealed that the hybrid plants (F-1) were mixoploid. in nature. The chromosome number of many somatic cells was 2n = 26, which was the sum of the chromosome number of the two parents. The chromosome number of other somatic cells was 2n = 38, similar to that of B. napus. The hybrid offspring (F-2) from the selfed hybrid plants (F-1) showed polymorphism. Among the hybrid offspring (F-2) some were nearly matroclinous and fertile, similar to B. napus. some others were intermediate between the two parents and less fertile, and a few were poorly developed and nearly infertile. From the hybrid offspring a few plants with improved seed-oil quality were obtained.展开更多
Erianthus arundinaceus is an important, closely related genus of Saccharum officinarum L. It is therefore important to understand how the chromosomes are transmitted when it hybridizes with sugarcane. The hybrids and ...Erianthus arundinaceus is an important, closely related genus of Saccharum officinarum L. It is therefore important to understand how the chromosomes are transmitted when it hybridizes with sugarcane. The hybrids and backcross progenies of S. officinarum and E. arundinaceus and their parents were used for Karyotype analysis and to study the law of chromosome transmission. The results showed that the somatic chromosome number of both of the E. arundinaceus Hainan92-105 and Hainan92-77 were 2n = 60 = 60sm, belonging to type 1 A, and the BC1 YC01-21 was 2n = 104 = 100m ＋ 4sm, belonging to type 2C. The other six tested clones belonged to type 2B. The both F1s YC96-66 and YC96-40 that originated from Badila （2n = 80 = 70m ＋ 10sm） with E. Arundinaceus were 2n = 70 = 68m ＋ 2sm, which suggests an n ＋ n transmission. The cross between YC96-66 （female parent） and CP84-1198 （male parent, 2n = 120 = 114m ＋ 6sm） also followed the same genetic law and the somatic chromosome number of their progeny, YC01-3 （2n = 105 = 95m ＋ 10sm）. The cross derived from YC96- 40 （female） and CP84-1198 （male）, YC01-21 had 2n = 104 = 100m ＋ 4sm chromosomes, following the same genetic law of n ＋ n. However, YC01-36 had 2n = 132 = 130m ＋ 2sm chromosomes, which suggests a 2n ＋ n chromosome transmission. It can be inferred that the inheritance of chromosomes was very complex in the BC1. The difference in chromosome number between clones was as high as 28. This could be explained by the 2n ＋ n transmission of chromosomes. In addition, as there was not be a regular number of haploids, this phenomenon is termed as disequilibrium hybridization.展开更多
In the cross between B. napus with OguCMSOrychophragmus violaceus, pre-fertilizatiocompatibility was observed. An intergeneric hybrid was successfully obtained by usinovary culture. The hybrid status was confirmed by ...In the cross between B. napus with OguCMSOrychophragmus violaceus, pre-fertilizatiocompatibility was observed. An intergeneric hybrid was successfully obtained by usinovary culture. The hybrid status was confirmed by cytology, morphology, fertilityisozyme and miosis analysis. The seed setting rate was 0.0072%. An amphidiploid of thhybrid was also produced by the use of chromosome-doubling method with 0.1% colchicinetreatment. Obtaining this hybrid and its amphidiploid has important theoretical anutilization value.展开更多
Taxodiorneria peizhongii Z. J. Ye, J. J. Zhang et S. H. Pan was regarded as a new Intergenerlc hybrid between Taxodlum mucronatum Tenore （as the female donor） and Cryptomeria fortunei Hoolbrenk ex Otto et Dletr （as...Taxodiorneria peizhongii Z. J. Ye, J. J. Zhang et S. H. Pan was regarded as a new Intergenerlc hybrid between Taxodlum mucronatum Tenore （as the female donor） and Cryptomeria fortunei Hoolbrenk ex Otto et Dletr （as the male donor）. To confirm the authenticity of the intergeneric hybrid, we analyzed the rbcL gene and the Internal transcribed spacer （ITS） of 26S-18S ribosomal RNA gene of the three species using polymerase chain reaction-restriction fragment length polymorphism （PCR-RFLP） and arbitrarily primed PCR （AP-PCR）, and ob- tained the following results：i） Taxodiomeria peizhongii had the same RFLP maps of the rbcL gene and the ITS as Taxodlum mucronatum, but was different from C. fortunei; II） a 311-bp PCR amplification product was obtained In C. fortunei by AP-PCR of ITS, but was not found in Taxodiomeria peizhongii. Our results have demonstrated that C. fortunei did not provide any genome for Taxodiomeria peizhongii, Implying that T. peizhongii Is not an Intergenerlc hybrid between the two species.展开更多
Through embryo culture, intergeneric hybrids were produced between common wheat,Triticum aestivum cv. Chinese Spring (CS) (2n= 6x = 42, AABBDD) and crested wheatgrass,Agropyron desertorum (2n =4x =28, PPPP) for the fi...Through embryo culture, intergeneric hybrids were produced between common wheat,Triticum aestivum cv. Chinese Spring (CS) (2n= 6x = 42, AABBDD) and crested wheatgrass,Agropyron desertorum (2n =4x =28, PPPP) for the first time. Their F_2 and BC_1 seeds havealso been successfully obtained by selfing and backcrossing with wheat in F_1 hybrids. Theseedlings of all F_1 hybrids tended to resemble their female parent, but they had more tillers,and their spike characteristics were between their parents. Average meiotic chromosomepairing at MI of F_1 hybrids was: 6.62Ⅰ+ 8.20RingⅡ+ 4.16RodⅡ+0.57Ⅲ+ 0.35Ⅳ+0.06Ⅴ+0.03Ⅵ. The successful experience of hybridization of common wheat with A. desertorum,the reason for the high level of chromosome pairing and self-fertility in the F_1 hybrids werediscussed. The F_2 and BC_1 seeds obtained in F_1 hybrids are of great importance to theory andpractice.展开更多
An efficient genetic transformation system and suitable promoters are essential prerequisites for gene expression studies and genetic engineering in streptomycetes.In this study,firstly,a genetic transformation system...An efficient genetic transformation system and suitable promoters are essential prerequisites for gene expression studies and genetic engineering in streptomycetes.In this study,firstly,a genetic transformation system based on intergeneric conjugation was developed in Streptomyces rimosus M527,a bacterial strain which exhibits strong antagonistic activity against a broad range of plant-pathogenic fungi.Some experimental parameters involved in this procedure were optimized,including the conjugative media,ratio of donor to recipient,heat shock temperature,and incubation time of mixed culture.Under the optimal conditions,a maximal conjugation frequency of 3.05^10-5 per recipie nt was obtai ned.Subseque ntly,based on the above developed and optimized tran sformati on system,the synthetic promoters SPL-21 and SPL-57,a native promoter potrB,and a constitutive promoter permE commonly used for gene expression in streptomycetes were selected and their activity was analyzed using gusA as a reporter gene in S.rimosus M527.Among the four tested promoters,SPL-21 exhibited the strongest expression activity and gave rise to a 2.2-fold increase in p-glucuronidase(GUS)activity compared with the control promoter permE.Promoter SPL-57 showed activity comparable to that of permE.Promoter potrB,which showed the lowest activity,showed a 50%decrease in GUS activity compared with the control permE.The transformation system developed in this study and the tested promotors provide a basis for the further modification of S.rimosus M527.展开更多
Introduction In order to improve cultivated wheat, a lot of intergeneric hybrids between wheat and its relatives, such as Aegilops, Secale, Haynaldia, Hordeum, Thinopyrum, Pseudoroegneria, Elytrigia, Elymus and Leymus...Introduction In order to improve cultivated wheat, a lot of intergeneric hybrids between wheat and its relatives, such as Aegilops, Secale, Haynaldia, Hordeum, Thinopyrum, Pseudoroegneria, Elytrigia, Elymus and Leymus have been obtained.展开更多
We succeeded in producing mature seed from a line of Brassica rapa ssp. pekinensis that had been hybridized with Raphanus sativus var. major. Our focus was on dominance of B. rapa ssp. pekinensis;radish (R. sativus va...We succeeded in producing mature seed from a line of Brassica rapa ssp. pekinensis that had been hybridized with Raphanus sativus var. major. Our focus was on dominance of B. rapa ssp. pekinensis;radish (R. sativus var. major) had no influence. Marker tests for similarity showed that the original CR291M-64 x HwiM-2 hybrid was an inbred CR291M-64, rather than a genuine cross;this appears to have resulted from weak self-incompatibility in this strain. The plants from the mature seed bloomed with reddish flowers differently shown up to present. The intergeneric hybrid between Brassica inbred and Raphanus hybrid was very weak in strength compared to the Brassica inbred which was self-pollinated even though the cause of the weak was not identified. The hybrids between Brassica hybrid, dominant and elite recessive, and Raphanus can be developed in large quantities using mature hybrid seed without resorting to ovule culture techniques.展开更多
A stable progeny was developed through induced mutation, using microspore culture, of the hybrid (F1F1) produced by crossing a newly synthesized, unstable allopolyploid (F1) and a stable cultivar, BB#1(F1) in xBrassic...A stable progeny was developed through induced mutation, using microspore culture, of the hybrid (F1F1) produced by crossing a newly synthesized, unstable allopolyploid (F1) and a stable cultivar, BB#1(F1) in xBrassicoraphanus. An F1F1 plant was subjected to the induced mutation system established during production of BB#1. Morphological characteristics of the progeny such as color, and leaf number and length, differed from those of BB#1. The bolting time of the progeny in spring cropping was very late compared to BB#1, allowing it to be grown to an adult plant in spring. Genomic in situ hybridization analysis of pollen mother cells at prophase I identified 19 bivalents, 10 from Brassica rapa and 9 from Raphanus sativus. The glucoraphenin content was almost identical to that of BB#1. Two cultivars are available in the baemoochae crop now. These results indicate that induced mutation using microspore culture is a viable method of stabilizing intergeneric allopolyploids between B. rapa and R. sativus.展开更多
Interspecific and intergeneric hybridizations have been widely used in plant genetics and breeding to construct stocks for genetic analysis and to introduce into crops the desirable traits and genes from their relativ...Interspecific and intergeneric hybridizations have been widely used in plant genetics and breeding to construct stocks for genetic analysis and to introduce into crops the desirable traits and genes from their relatives. The intergeneric crosses between Brassica juncea (L.) Czern. & Coss., B. carinata A. Braun and Orychophragmus violaceus (L.) O. E. Schulz were made and the plants produced were subjected to genomic in situ hybridization analysis. The mixoploids from the cross with B. juncea were divided into three groups. The partially fertile mixoploids in the first group (2n = 36—42) mainly contained the somatic cells and pollen mother cells (PMCs) with the 36 chromosomes of B. juncea and additional chromosomes of O. violaceus. The mixoploids (2n = 30—36) in the second and third groups were morphologically quite similar to the mother plants B. juncea and showed nearly normal fertility. The plants in the second group produced the majority of PMCs (2n = 36) with their chromosomes paired and segregated normally, but 1—4 pairs of the O. violaceus chromosomes were included in some PMCs. The plants in the third group produced only PMCs with the 36 B. juncea chromosomes, which were paired and segregated normally. The mixoploids (2n = 29—34) from the cross with B. carinata produced the majority of PMCs (2n = 34) with normal chromosome pairing and segregation, but some plants had some PMCs with 1—3 pairs of chromosomes from O. violaceus and other plants had only PMCs with the B. carinata chromosomes. The Brassica homozygous plants and aneuploids with complete or partial chromo-some complements of Brassica parents and various numbers of O. violaceus chromosomes were derived from these progeny plants. The results in this study provided the molecular cytogenetic evidence for the separation of parental genomes which was previously proposed to occur in the hybridizations of these two genera.展开更多
Brassica rapa(AA,2n=20)and Raphanus sativus(RR,2n=18)are popular vegetables containing multiple secondary metabolites,such as flavonoids and anthocyanins.Nevertheless,fewstudies on miRNA expression profiles and potent...Brassica rapa(AA,2n=20)and Raphanus sativus(RR,2n=18)are popular vegetables containing multiple secondary metabolites,such as flavonoids and anthocyanins.Nevertheless,fewstudies on miRNA expression profiles and potential regulatory network of flavonoid metabolism have been reported in the intergeneric hybrid of B.rapa and R.sativus(Brassicacoraphanus,AARR,2n=38).Here,themiRNAs of Brassicacoraphanus and its parents were first identified by small RNA sequencing.It was revealed that 315 conserved miRNAs and 193 novel miRNAs were found in Brassicacoraphanus and its parents.Moreover,the miRNA expression profiles were characterized and 204 miRNAs with differential expression were obtained.Further analysis showed that 184 miRNAs were non-additively expressed in Brassicacoraphanus.At last,the potential regulatory network of flavonoid metabolism in Brassicacoraphanus was analyzed by multi-omics data,suggesting possible roles of miR858a and miR157a in regulating flavonoid synthesis pathway in Brassicacoraphanus.Taken together,this study provides useful resources for probing globalmiRNA expression patterns in Brassicacoraphanus,which facilitates regulatory mechanism research on the biosynthesis pathway of secondary metabolites in Brassicacoraphanus.展开更多
Optimal conditions for protoplasts formation of marine Actinomycete sp. isolate M048 were described, dense and disperse mycelia were cultured in SGGP medium, 0.5% glycine, lysozyme exposure （2 mg/cm^3, 37 ℃, 40 min...Optimal conditions for protoplasts formation of marine Actinomycete sp. isolate M048 were described, dense and disperse mycelia were cultured in SGGP medium, 0.5% glycine, lysozyme exposure （2 mg/cm^3, 37 ℃, 40 min）, and the concentration of sucrose in protoplast buffer was 0.4 mol/dm^3 for keeping the balance of osmotic pressure. Using PEG-mediated pmtoplasts transformarion, the transformation frequency was 89 transformants per microgramme of pIJ702. Meanwhile, an effective transformation procedure was established based on intergeneric conjugation from E. coli ET12567 （pUZS002） using shuttle vectors pPM801, pPM803 and a φC31-derived integration vector pIJ8600 containing onT and attP fragments. Transformation frequencies were 5.30 ×10^-4 ±0.26 ×10^-4 , 8.92 ×10^-4 ±0. 19 ×10^-4 and 6.38 ×10^-5 ±0.41×10^-5 respectively. Further, the heterologous expression of the allophycocyanin gene （apc） in the strain M048 was used to demonstrate this transformation system. SDS - PAGE and Western blot analysis confirmed the expression of recombinant APC （rAPC）.展开更多
A comparative study on the photosynthetic parameters among intergeneric progenies derived from \%Oryza sativa\% L.×\%Sorghum vulgare\% L., its maternal parent Gui 630 and commercial 3\|line hybrid rice Shanyou 63...A comparative study on the photosynthetic parameters among intergeneric progenies derived from \%Oryza sativa\% L.×\%Sorghum vulgare\% L., its maternal parent Gui 630 and commercial 3\|line hybrid rice Shanyou 63 in pot experiment in greenhouse was conducted. The morphological and photosynthetic characters of canopy leaves and chlorophyll fluorescence kinetic parameters including \%F\%\-v/\%F\%\-m, \%F\%\-v/\%F\%\-0, photochemical quenching coefficient and non\|photochemical coefficient of canopy leaves of 3 varieties were measured. The results showed the progeny, Yuanyou 1, derived from an intergeneric cross of rice and sorghum possesses better canopy spatial architecture with thicker, heavier and bigger canopy leaf than its maternal parent Gui 630. Higher photosynthetic rate due to higher chlorophyll content, higher primary energy transformation efficiency, potential of PSII and non\|photochemical quenching coefficient (\%q\%\-E) were also measured in Yuanyou 1. These explain partly why the intergeneric progeny has higher biomass production, and better tolerance to adverse conditions and higher field yields even under stress conditions.展开更多
To detect the intergeneric hybridization between the oyster Crassostrea angulata and Saccostrea cucullata coexisting along the southern coast of China, reciprocal crosses were conducted between the two species. Barrie...To detect the intergeneric hybridization between the oyster Crassostrea angulata and Saccostrea cucullata coexisting along the southern coast of China, reciprocal crosses were conducted between the two species. Barriers for sperm recognizing, binding, penetrating the egg, and forming the pronucleus were detected by fluorescence staining. From the results, although fertilization success was observed in hybrid crosses, the overall fertilization rate was lower than that of intraspecific crosses. A large number of hybrid larvae died at 6–8 d after hatching, and those survived could not complete metamorphosis. C. angulata ♀× S. cucullata ♂ larvae had a growth rate similar to that of the maternal species, whereas S. cucullata ♀× C. angulata ♂ larvae grew the slowest among all crosses. Molecular genetics analysis revealed that hybrid progeny were amphimixis hybrids. This study demonstrated that hybrid embryos generated by crossing C. angulata and S. cucullata could develop normally to the larval state, but could not complete metamorphosis and then develop to the spat stage. Thus, there is a post-reproductive isolation between C. angulata and S. cucullata.展开更多
基金Supported by the National Natural Science Foundation of China(30270827)the Program for Changjiang Scholars and Innovative Research in Universities(10418).
文摘Haynaldia villosa possesses a lot of important agronomic traits and has been a powerful gene resource for wheat improvement. However, only several wheat-H, villosa translocation lines have been reported so far. In this study, we attempted to develop an efficient method for inducing wheat-H, villosa chromosomal translocations. Triticum durum- Haynaldia villosa amphiploid pollen treated with 1 200 rad ^60Co-y-rays was pollinated to Triticum aestivum cv. ＇Chinese Spring＇. Ninety-eight intergeneric translocated chromosomes between T. durum and H. villosa were detected by genomic in situ hybridization in 44 of 61 M1 plants, indicating a translocation occurrence frequency of 72.1%; much higher than ever reported. There were 26, 62 and 10 translocated chromosomes involving whole arm translocations, terminal translocations, and intercarlary translocations, respectively. Of the total 108 breakage-fusion events, 79 involved interstitial regions and 29 involved centric regions. The ratio of small segment terminal translocations （W.W-V） was much higher than that of large segment terminal translocations （W-V.V）. All of the M1 plants were self-sterile, and their backcross progeny was all obtained with ＇Chinese Spring＇ as pollen donors. Transmission analysis showed that most of the translocations were transmittable. This study provides a new strategy for rapid mass production of wheat-alien chromosomal translocations, especially terminal translocations that will be more significant for wheat improvement.
文摘: Electrically induced protoplast fusion was used to produce somatic hybrids between Brassica napus L. and Sinapis alba L. Seven hybrids were obtained and verified by the simple sequence repeat and cleaved amplified polymorphic sequence analysis of the gene fael, indicating that the characteristic bands from S. alba were present in the hybrids. The hybridity was also confirmed by chromosome number counting because the hybrids possessed 62 chromosomes, corresponding to the sum of fusion-parent chromosomes. Chromosome pairing at meiosis was predominantly normal, which led to high pollen fertility, ranging from 66% to 77%. All hybrids were grown to full maturity and could be fertilized and set seed after self-pollination or back-crosses with B. napus. The morphology of the hybrids resembled characteristics from both parental species. An analysis of the fatty acid composition in the seeds of F1 plants was conducted and the seeds were found to contain different amounts of erucic acid, ranging from 11.0% to 52.1%.
文摘The intergeneric hybridization between Brassica napus L. cv. oro and Matthiola incana (L.) R. Br. was carried out to study the phytogenetic peculiarities of the hybrid plants. In order to improve the oil quality of rape seed, ovaries of B. napus pollinated with pollen of M. incana, were cut off and inoculated onto MS media supplemented with various plant hormones at the 7th day after pollination. Two mature embryos were obtained from 750 pollinated ovaries cultured in vitro. The percentage of seed set was 0.26%. The mature embryos were transferred onto the MS media supplemented with 2.0 mg/L 6-BA + 0.1 mg/L NAA, and a compound bud was produced later. The compound bud was then cut into a number of single buds, which were transferred onto fresh media. Twenty-two plantlets in vitro were developed from the above single buds. The hybrid plants (F-1) were basically intermediate between the two parents in many,characters with a few showing hybrid vigor. The fertility of hybrid plants (F-1) was poor. Cytological studies revealed that the hybrid plants (F-1) were mixoploid. in nature. The chromosome number of many somatic cells was 2n = 26, which was the sum of the chromosome number of the two parents. The chromosome number of other somatic cells was 2n = 38, similar to that of B. napus. The hybrid offspring (F-2) from the selfed hybrid plants (F-1) showed polymorphism. Among the hybrid offspring (F-2) some were nearly matroclinous and fertile, similar to B. napus. some others were intermediate between the two parents and less fertile, and a few were poorly developed and nearly infertile. From the hybrid offspring a few plants with improved seed-oil quality were obtained.
基金supported by the National Natural Science Foudation of China (30671329)the National Key Technologies R&D Program of Chinaduring the 11th Five-Year Plan period (2006BAD06-4)
文摘Erianthus arundinaceus is an important, closely related genus of Saccharum officinarum L. It is therefore important to understand how the chromosomes are transmitted when it hybridizes with sugarcane. The hybrids and backcross progenies of S. officinarum and E. arundinaceus and their parents were used for Karyotype analysis and to study the law of chromosome transmission. The results showed that the somatic chromosome number of both of the E. arundinaceus Hainan92-105 and Hainan92-77 were 2n = 60 = 60sm, belonging to type 1 A, and the BC1 YC01-21 was 2n = 104 = 100m ＋ 4sm, belonging to type 2C. The other six tested clones belonged to type 2B. The both F1s YC96-66 and YC96-40 that originated from Badila （2n = 80 = 70m ＋ 10sm） with E. Arundinaceus were 2n = 70 = 68m ＋ 2sm, which suggests an n ＋ n transmission. The cross between YC96-66 （female parent） and CP84-1198 （male parent, 2n = 120 = 114m ＋ 6sm） also followed the same genetic law and the somatic chromosome number of their progeny, YC01-3 （2n = 105 = 95m ＋ 10sm）. The cross derived from YC96- 40 （female） and CP84-1198 （male）, YC01-21 had 2n = 104 = 100m ＋ 4sm chromosomes, following the same genetic law of n ＋ n. However, YC01-36 had 2n = 132 = 130m ＋ 2sm chromosomes, which suggests a 2n ＋ n chromosome transmission. It can be inferred that the inheritance of chromosomes was very complex in the BC1. The difference in chromosome number between clones was as high as 28. This could be explained by the 2n ＋ n transmission of chromosomes. In addition, as there was not be a regular number of haploids, this phenomenon is termed as disequilibrium hybridization.
基金supported by the National Natura1 Science Foundation of China(39470457) the Ninth Five-Year Major Program of China.
文摘In the cross between B. napus with OguCMSOrychophragmus violaceus, pre-fertilizatiocompatibility was observed. An intergeneric hybrid was successfully obtained by usinovary culture. The hybrid status was confirmed by cytology, morphology, fertilityisozyme and miosis analysis. The seed setting rate was 0.0072%. An amphidiploid of thhybrid was also produced by the use of chromosome-doubling method with 0.1% colchicinetreatment. Obtaining this hybrid and its amphidiploid has important theoretical anutilization value.
基金National Natural Science Foundation of China （39970061）.
文摘Taxodiorneria peizhongii Z. J. Ye, J. J. Zhang et S. H. Pan was regarded as a new Intergenerlc hybrid between Taxodlum mucronatum Tenore （as the female donor） and Cryptomeria fortunei Hoolbrenk ex Otto et Dletr （as the male donor）. To confirm the authenticity of the intergeneric hybrid, we analyzed the rbcL gene and the Internal transcribed spacer （ITS） of 26S-18S ribosomal RNA gene of the three species using polymerase chain reaction-restriction fragment length polymorphism （PCR-RFLP） and arbitrarily primed PCR （AP-PCR）, and ob- tained the following results：i） Taxodiomeria peizhongii had the same RFLP maps of the rbcL gene and the ITS as Taxodlum mucronatum, but was different from C. fortunei; II） a 311-bp PCR amplification product was obtained In C. fortunei by AP-PCR of ITS, but was not found in Taxodiomeria peizhongii. Our results have demonstrated that C. fortunei did not provide any genome for Taxodiomeria peizhongii, Implying that T. peizhongii Is not an Intergenerlc hybrid between the two species.
文摘Through embryo culture, intergeneric hybrids were produced between common wheat,Triticum aestivum cv. Chinese Spring (CS) (2n= 6x = 42, AABBDD) and crested wheatgrass,Agropyron desertorum (2n =4x =28, PPPP) for the first time. Their F_2 and BC_1 seeds havealso been successfully obtained by selfing and backcrossing with wheat in F_1 hybrids. Theseedlings of all F_1 hybrids tended to resemble their female parent, but they had more tillers,and their spike characteristics were between their parents. Average meiotic chromosomepairing at MI of F_1 hybrids was: 6.62Ⅰ+ 8.20RingⅡ+ 4.16RodⅡ+0.57Ⅲ+ 0.35Ⅳ+0.06Ⅴ+0.03Ⅵ. The successful experience of hybridization of common wheat with A. desertorum,the reason for the high level of chromosome pairing and self-fertility in the F_1 hybrids werediscussed. The F_2 and BC_1 seeds obtained in F_1 hybrids are of great importance to theory andpractice.
基金Project supported by the National Natural Science Foundation of China(Nos.31772213 and 31972320)the Excellent Youth Fund of Zhejiang Province,China(No.LR17C140002)
文摘An efficient genetic transformation system and suitable promoters are essential prerequisites for gene expression studies and genetic engineering in streptomycetes.In this study,firstly,a genetic transformation system based on intergeneric conjugation was developed in Streptomyces rimosus M527,a bacterial strain which exhibits strong antagonistic activity against a broad range of plant-pathogenic fungi.Some experimental parameters involved in this procedure were optimized,including the conjugative media,ratio of donor to recipient,heat shock temperature,and incubation time of mixed culture.Under the optimal conditions,a maximal conjugation frequency of 3.05^10-5 per recipie nt was obtai ned.Subseque ntly,based on the above developed and optimized tran sformati on system,the synthetic promoters SPL-21 and SPL-57,a native promoter potrB,and a constitutive promoter permE commonly used for gene expression in streptomycetes were selected and their activity was analyzed using gusA as a reporter gene in S.rimosus M527.Among the four tested promoters,SPL-21 exhibited the strongest expression activity and gave rise to a 2.2-fold increase in p-glucuronidase(GUS)activity compared with the control promoter permE.Promoter SPL-57 showed activity comparable to that of permE.Promoter potrB,which showed the lowest activity,showed a 50%decrease in GUS activity compared with the control permE.The transformation system developed in this study and the tested promotors provide a basis for the further modification of S.rimosus M527.
文摘Introduction In order to improve cultivated wheat, a lot of intergeneric hybrids between wheat and its relatives, such as Aegilops, Secale, Haynaldia, Hordeum, Thinopyrum, Pseudoroegneria, Elytrigia, Elymus and Leymus have been obtained.
文摘We succeeded in producing mature seed from a line of Brassica rapa ssp. pekinensis that had been hybridized with Raphanus sativus var. major. Our focus was on dominance of B. rapa ssp. pekinensis;radish (R. sativus var. major) had no influence. Marker tests for similarity showed that the original CR291M-64 x HwiM-2 hybrid was an inbred CR291M-64, rather than a genuine cross;this appears to have resulted from weak self-incompatibility in this strain. The plants from the mature seed bloomed with reddish flowers differently shown up to present. The intergeneric hybrid between Brassica inbred and Raphanus hybrid was very weak in strength compared to the Brassica inbred which was self-pollinated even though the cause of the weak was not identified. The hybrids between Brassica hybrid, dominant and elite recessive, and Raphanus can be developed in large quantities using mature hybrid seed without resorting to ovule culture techniques.
文摘A stable progeny was developed through induced mutation, using microspore culture, of the hybrid (F1F1) produced by crossing a newly synthesized, unstable allopolyploid (F1) and a stable cultivar, BB#1(F1) in xBrassicoraphanus. An F1F1 plant was subjected to the induced mutation system established during production of BB#1. Morphological characteristics of the progeny such as color, and leaf number and length, differed from those of BB#1. The bolting time of the progeny in spring cropping was very late compared to BB#1, allowing it to be grown to an adult plant in spring. Genomic in situ hybridization analysis of pollen mother cells at prophase I identified 19 bivalents, 10 from Brassica rapa and 9 from Raphanus sativus. The glucoraphenin content was almost identical to that of BB#1. Two cultivars are available in the baemoochae crop now. These results indicate that induced mutation using microspore culture is a viable method of stabilizing intergeneric allopolyploids between B. rapa and R. sativus.
基金supported by the National Natural Science Foundation of China (Grant No. 30070413) and China Scholarship Council. References
文摘Interspecific and intergeneric hybridizations have been widely used in plant genetics and breeding to construct stocks for genetic analysis and to introduce into crops the desirable traits and genes from their relatives. The intergeneric crosses between Brassica juncea (L.) Czern. & Coss., B. carinata A. Braun and Orychophragmus violaceus (L.) O. E. Schulz were made and the plants produced were subjected to genomic in situ hybridization analysis. The mixoploids from the cross with B. juncea were divided into three groups. The partially fertile mixoploids in the first group (2n = 36—42) mainly contained the somatic cells and pollen mother cells (PMCs) with the 36 chromosomes of B. juncea and additional chromosomes of O. violaceus. The mixoploids (2n = 30—36) in the second and third groups were morphologically quite similar to the mother plants B. juncea and showed nearly normal fertility. The plants in the second group produced the majority of PMCs (2n = 36) with their chromosomes paired and segregated normally, but 1—4 pairs of the O. violaceus chromosomes were included in some PMCs. The plants in the third group produced only PMCs with the 36 B. juncea chromosomes, which were paired and segregated normally. The mixoploids (2n = 29—34) from the cross with B. carinata produced the majority of PMCs (2n = 34) with normal chromosome pairing and segregation, but some plants had some PMCs with 1—3 pairs of chromosomes from O. violaceus and other plants had only PMCs with the B. carinata chromosomes. The Brassica homozygous plants and aneuploids with complete or partial chromo-some complements of Brassica parents and various numbers of O. violaceus chromosomes were derived from these progeny plants. The results in this study provided the molecular cytogenetic evidence for the separation of parental genomes which was previously proposed to occur in the hybridizations of these two genera.
基金This research was funded by National key research and Development Program(Grant No.2017YFD0101701)the New Century Talents Support Program by the Ministry of Education of China(Grant No.NCET110172)the Natural Science Foundation of Hubei Province,China(Grant No.2019CFB476).We would like to thank Prof.Chuang Ma(Northwest A&F University)for helping to analyze the sequencing data.
文摘Brassica rapa(AA,2n=20)and Raphanus sativus(RR,2n=18)are popular vegetables containing multiple secondary metabolites,such as flavonoids and anthocyanins.Nevertheless,fewstudies on miRNA expression profiles and potential regulatory network of flavonoid metabolism have been reported in the intergeneric hybrid of B.rapa and R.sativus(Brassicacoraphanus,AARR,2n=38).Here,themiRNAs of Brassicacoraphanus and its parents were first identified by small RNA sequencing.It was revealed that 315 conserved miRNAs and 193 novel miRNAs were found in Brassicacoraphanus and its parents.Moreover,the miRNA expression profiles were characterized and 204 miRNAs with differential expression were obtained.Further analysis showed that 184 miRNAs were non-additively expressed in Brassicacoraphanus.At last,the potential regulatory network of flavonoid metabolism in Brassicacoraphanus was analyzed by multi-omics data,suggesting possible roles of miR858a and miR157a in regulating flavonoid synthesis pathway in Brassicacoraphanus.Taken together,this study provides useful resources for probing globalmiRNA expression patterns in Brassicacoraphanus,which facilitates regulatory mechanism research on the biosynthesis pathway of secondary metabolites in Brassicacoraphanus.
文摘Optimal conditions for protoplasts formation of marine Actinomycete sp. isolate M048 were described, dense and disperse mycelia were cultured in SGGP medium, 0.5% glycine, lysozyme exposure （2 mg/cm^3, 37 ℃, 40 min）, and the concentration of sucrose in protoplast buffer was 0.4 mol/dm^3 for keeping the balance of osmotic pressure. Using PEG-mediated pmtoplasts transformarion, the transformation frequency was 89 transformants per microgramme of pIJ702. Meanwhile, an effective transformation procedure was established based on intergeneric conjugation from E. coli ET12567 （pUZS002） using shuttle vectors pPM801, pPM803 and a φC31-derived integration vector pIJ8600 containing onT and attP fragments. Transformation frequencies were 5.30 ×10^-4 ±0.26 ×10^-4 , 8.92 ×10^-4 ±0. 19 ×10^-4 and 6.38 ×10^-5 ±0.41×10^-5 respectively. Further, the heterologous expression of the allophycocyanin gene （apc） in the strain M048 was used to demonstrate this transformation system. SDS - PAGE and Western blot analysis confirmed the expression of recombinant APC （rAPC）.
文摘A comparative study on the photosynthetic parameters among intergeneric progenies derived from \%Oryza sativa\% L.×\%Sorghum vulgare\% L., its maternal parent Gui 630 and commercial 3\|line hybrid rice Shanyou 63 in pot experiment in greenhouse was conducted. The morphological and photosynthetic characters of canopy leaves and chlorophyll fluorescence kinetic parameters including \%F\%\-v/\%F\%\-m, \%F\%\-v/\%F\%\-0, photochemical quenching coefficient and non\|photochemical coefficient of canopy leaves of 3 varieties were measured. The results showed the progeny, Yuanyou 1, derived from an intergeneric cross of rice and sorghum possesses better canopy spatial architecture with thicker, heavier and bigger canopy leaf than its maternal parent Gui 630. Higher photosynthetic rate due to higher chlorophyll content, higher primary energy transformation efficiency, potential of PSII and non\|photochemical quenching coefficient (\%q\%\-E) were also measured in Yuanyou 1. These explain partly why the intergeneric progeny has higher biomass production, and better tolerance to adverse conditions and higher field yields even under stress conditions.
文摘To detect the intergeneric hybridization between the oyster Crassostrea angulata and Saccostrea cucullata coexisting along the southern coast of China, reciprocal crosses were conducted between the two species. Barriers for sperm recognizing, binding, penetrating the egg, and forming the pronucleus were detected by fluorescence staining. From the results, although fertilization success was observed in hybrid crosses, the overall fertilization rate was lower than that of intraspecific crosses. A large number of hybrid larvae died at 6–8 d after hatching, and those survived could not complete metamorphosis. C. angulata ♀× S. cucullata ♂ larvae had a growth rate similar to that of the maternal species, whereas S. cucullata ♀× C. angulata ♂ larvae grew the slowest among all crosses. Molecular genetics analysis revealed that hybrid progeny were amphimixis hybrids. This study demonstrated that hybrid embryos generated by crossing C. angulata and S. cucullata could develop normally to the larval state, but could not complete metamorphosis and then develop to the spat stage. Thus, there is a post-reproductive isolation between C. angulata and S. cucullata.
