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1.
Genetic fingerprinting for determining the mode of reproduction in Paspalum notatum, a subtropical apomictic forage grass 总被引:3,自引:0,他引:3
J. P. A. Ortiz S. C. Pessino O. Leblanc M. D. Hayward C. L. Quarín 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1997,95(5-6):850-856
Paspalum is an important genus of the family Gramineae that includes several valuable forage grasses. Many of the species are polyploid
and either obligate or facultative apomicts. Cyto-embryological observations of several tetraploid genotypes of P. notatum were performed to determine their mode of reproduction. Afterwards, selfed progenies of the genotypes F131, Q3664 and Q4117
were analysed using RFLP and RAPD genetic fingerprints to identify maternal and non-maternal (aberrant) plants, and to establish
the degree of apomictic reproduction. Five maize clones and six primers were used for detecting genetic deviations from the
maternal profile. Maize clones umc379, umc384 and umc318 and primers OPG10 and OPI4 were the most informative for discriminating
between maternal and aberrant individuals within the progenies of F131 and Q3664. The combined results of three RFLP clones
or 4–6 RAPD primers were necessary to ascertain the mode of reproduction in plants F131 and Q3664. The results obtained with
the RFLP and RAPD markers were in agreement with the cyto-embryological studies in ascertaining the mode and degree of apomictic
reproduction. Plant F131 showed a completely sexual reproductive behaviour, Q3664 an elevated expression of sexuality, while
Q4117 was highly apomictic. A fingerprint analysis of an outcrossing population, aimed at the identification of hybrid plants,
was also performed. Maize clones um318 and umc379 and primers OPC2 and OPC9 were used. The presence of specific bands belonging
to the male parent permitted a rapid and easy detection of hybrids. The methodology described here can be applied both for
the characterisation of P. notatum populations and to identify hybrid progenies in Paspalum breeding programs.
Received: 5 March 1997 / Accepted: 13 May 1997 相似文献
2.
Characterization of zygotic and nucellar seedlings from sour orange-like citrus rootstock candidates using RAPD and EST-SSR markers 总被引:1,自引:0,他引:1
Madhugiri Nageswara Rao Jaya R. Soneji Chunxian Chen Shu Huang Fred G. Gmitter Jr. 《Tree Genetics & Genomes》2008,4(1):113-124
A series of crosses designed for introgression of mandarin (Citrus reticulata Blanco) and pummelo (C. maxima Merr.) germplasm, to develop an alternative rootstock to sour orange (C. aurantium L.), were carried out. It is necessary to identify those hybrids that yield nucellar seedlings for rootstock propagation.
Rootstocks can be developed through traditional plant breeding methods; however, the ability to screen and select for economically
important traits (such as production of true nucellar seedlings) in an efficient fashion is limited by the difficulties of
screening techniques based on whole plant performance. To address these problems, we have used randomly amplified polymorphic
DNA (RAPD) and fluorescently labeled expressed sequence tag simple sequence repeat (EST-SSR) molecular markers. A total of
204 individual seedlings obtained from 34 hybrid parental plants were successfully characterized using five RAPD primers.
Ten hybrid parents and their progenies, found to be genetically similar among themselves, were selected for more scrutiny
using eight EST-SSR primer pairs. The degrees of genetic similarity (nucellars) among progeny seedlings were determined and
compared with that of their parents. The mean genetic similarity varied from 67–99% among the selected rootstock candidates
screened. The genetic similarity relationship identified using RAPD and EST-SSR molecular markers was highly concordant (p = 0.001). Two elite rootstock candidates (B6R5T56; B6R11T129) that seem to be ideal for future mandarin and pummelo derived
rootstock breeding programs have been identified. Our results indicate that either RAPD or EST-SSR analyses could be equally
successful in identifying true nucellars among the progenies obtained from introgression crosses of mandarin and pummelo,
thus improving the accuracy of early selection in a citrus rootstock breeding program. 相似文献
3.
The method of polymerase chain reaction with random primers (RAPD PCR) was used to identify the progeny of the crosses between
three sturgeon species, Amur sturgeon (Acipenser schrenckii Brandt, 1869), Siberian sturgeon (A. baerii Brandt, 1869), and sterlet (A. ruthenus Linnaeus, 1758). Using ten primers, genetic variation in 70 yearlings, produced in seven individual crosses: Acipenser schrenckii × A. schrenckii, A. baerii × A. baerii, A. ruthenus × A. ruthenus, A. schrenckii × A. baerii, A. baerii × A. schrenckii, A. schrenckii × A. ruthenus, and A. ruthenus × A. schrenckii was described and evaluated. It was demonstrated that the samples composed of hybrids from individual crosses were more variable
than the samples of parental species. On the other hand, pooled samples of hybrids from two cross directions were genetically
less variable than the pooled samples of their parents. The three main features of the hybrid RAPD profiles identified included:
(1) preservation of marker DNA fragments of both parents in one genome; (2) presence of specific DNA fragments, absent from
both parents; and (3) dependence of the frequency of some DNA fragments from the cross direction. Multidimensional scaling
clearly distinguishes in the space of three coordinates the individuals of original species and the hybrid progeny with differentiation
in the groups of direct and backcross hybrids. Analysis of relationships (UPGMA and NJ) pointed to substantial differentiation
between the species, as well as between the species and hybrid progeny. Close genetic relationships between direct and backcross
hybrids were demonstrated. Multilocus RAPD markers in association with statistical methods are considered to be the useful
tool for discrimination of interspecific hybrids of sturgeon. Possible reasons for the differences in the hybrid RAPD profiles
are discussed.
Original Russian Text ? K.V. Rozhkovan, G.N. Chelomina, E.I. Rachek, 2008, published in Genetika, 2008, Vol. 44, No. 11, pp.
1453–1460. 相似文献
4.
J. O. Rasmussen S. Waara O. S. Rasmussen 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1997,95(1-2):41-49
Recipient protoplasts from three Solanum tuberosum genotypes, cv ‘Folva’ (2n=4x=48), cv ‘Matilda’ (4n) and ‘161 : 14’ (2n), were electrofused with X-ray-irradiated donor protoplasts
from two wild species S. spegazzinii (2n) or S. microdontum×S. vernei (2n). Prior to fusion, protoplasts were fluorescence-labelled with either fluorescein diacetate or scopoletin. Fusion products
were identified by dual fluorescence and selected by micromanipulation or fluorescence-activated cell sorting (FACS). All
putative hybrid plants were analysed by the random amplified polymorphic DNA (RAPD) technique. Our analysis demonstrates that
each asymmetric hybrid plant has an individual and stable profile of donor-specific RAPD bands. The irradiation of donor protoplasts
hampered the growth of selected heterofusion products in a dose-dependent way. Irradiation resulted in donor chromosome elimination,
but not in a dose dependent way, in the tested interval. In asymmetric hybrids with the S. spegazzinii donor 33–68% of the donor-specific RAPD bands were missing, indicating a similar level of chromosome elimination. In asymmetric
hybrid plants with the S. microdontum×S. vernei donor 74–95% of the donor RAPD bands were missing. Chromosome countings revealed that these hybrids had chromosome numbers
equal to or below the chromosome numbers found in the tetraploid recipients. This is the first time that highly asymmetric
hybrid plants between two tetraploid potato recipients and the donor S. microdontum×S. vernei have been obtained.
Received : 16 December 1996 / Accepted: 21 February 1997 相似文献
5.
G. Barcaccia A. Mazzucato A. Belardinelli M. Pezzotti S. Lucretti M. Falcinelli 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1997,95(4):516-524
Moving gene(s) responsible for the apomictic trait into crop plants that naturally reproduce through a sexual process would
open up new areas in plant breeding and agricultural systems. Kentucky bluegrass (Poa pratensis L.) is one of the most important forage and turf grasses in temperate climates. It reproduces through facultative aposporous
parthenogenesis, but the reproductive behaviour ranges naturally from nearly obligate apomixis to complete sexuality. In addition
to apomictic reproduction, sexual hybridization may take place. Selfing may also occur, and occasionally reduced egg cells
may develop through parthenogenesis generating (poly)haploids. The inheritance of parental genomes was assessed in Kentucky
bluegrass progenies by employing RAPD markers in combination with flow cytometry (FCM). Nine progenies from different crosses
carried out between completely sexual and highly apomictic genotypes were evaluated in order to probe the reproductive behaviour
of the mother plants and to distinguish the different classes of aberrant plants. Not only were maternals and balanced BII hybrids recorded, but so were (poly)triploid BIII hybrids, selfs, and (poly)haploids. The application of these techniques demonstrated that FCM analysis accurately distinguishes
the n, 2n, and 3n ploidy levels of progenies, and that RAPD markers unequivocally recognize progenies of apomictic and hybrid
origin. The occurrence of aneusomaty was documented in one of the selected sexual genotypes, whose crossed progeny plants
manifested two distinct classes of ploidy. The nomenclature BI was adopted to refer to hybrids with a hypodiploid nuclear condition. On the whole, the FCM analysis confirmed most of the
RAPD data. The combined evaluation of DNA markers and DNA contents proved to be an efficient screening tool for scoring maternal
plants, assessing the genetic origin of aberrant plants, and quantifying the inheritance of parental genomes in Kentucky bluegrass.
Hybrid populations from sexual×apomictic matings that segregate for the mode of reproduction represent a valuable basis for
attempting to identify molecular markers linked to the apomixis gene(s).
Received: 11 November 1996/Accepted: 22 November 1996 相似文献
6.
Paternity and ploidy segregation of progenies derived from tetraploid Malus xiaojinensis 总被引:1,自引:0,他引:1
Lei Wang DeGuo Han Chao Gao Yi Wang XinZhong Zhang XueFeng Xu ZhenHai Han 《Tree Genetics & Genomes》2012,8(6):1469-1476
Apomixis is usually subdivided into parthenogenesis, apogamy, and apospory on the basis of different mechanisms of development and cytogenetic effects. Although most plants and animals undergo sexual reproduction to multiply, it is important to understand the role of apomixis in plant reproduction because of its useful applications in the breeding and propagation of some crops. Tetraploid Malus xiaojinensis Cheng et Jiang is a typical facultative apomictic plant species. Paternity and ploidy analyses of M. xiaojinensis seedlings were performed with flow cytometry in conjunction with microsatellite and single nucleotide polymorphism markers. The proportion of apomictic derived progeny of M. xiaojinensis × Malus baccata was 54.05, 53.96, and 43.55 % from 2008 to 2010, respectively. The progeny of M. xiaojinensis × M. baccata comprised hybrids of 2x, 3x, 4x, or 5x ploidy, whereas apomictic offspring were 2x, 3x, or 4x. Among the apomictic derived progeny, the ploidy of restituted apomictic progeny was 2x, 3x, or 4x, whereas that of nonrestituted apomictic progeny was 4x only. The proportions of the different types of apomictic derived progeny differed among the years 2008 to 2010. The ploidy of progeny from emasculated flowers also segregated into 2x, 3x, and 4x individuals. These results indicate that both parthenogenesis and unreduced meiotic diplospory play important roles in apomictic reproduction in M. xiaojinensis. 相似文献
7.
Rodrigues-Otubo B.M. de O. Penteado M.I. do Valle C.B. 《Plant Cell, Tissue and Organ Culture》2000,61(3):175-182
Age of explant and six different media were evaluated with the objective of regenerating higher numbers of interspecific hybrids
between sexual and apomictic Brachiaria. Immature embryos of 7–8, 9–10 and 11–12 days after pollination (DAP), from artificial hybridization between Brachiaria ruziziensis (R) as female parent, and B. brizantha (B) or B. decumbens (D) as male parent, were cultured in modified MS media (M4) – supplemented with different combinations of growth regulators
and vitamins. Embryos cultured 9–12 DAP showed high percentage (85–100%) of germination for all the crosses examined. Germination
and survival rates varied according to accessions within crosses. Six different media (all modified MS with different growth
regulators and vitamins) were tested with the objective of inducing multiple shoots from 7 to 10 DAP embryos, from crosses
between R × B. The media M1, supplemented with Kinetin (13.94 μM) and NAA (5.37 μM), and media M3, supplemented with BA (4.44
μM and IAA 2.85 μM), regenerated adventitious shoots and calli about 30–40 days after inoculation. The highest multiplication
rate observed was 2.85 shoots per explant in media M1, 60–70 days after culturing. Two other media, M6, supplemented with
2,4-D (13.57 μM) and M2, with 2,4-D (9.05 μM) and BA (8.87 μM) exclusively induced the formation of calli. The described protocols
proved to be efficient in regenerating healthy seedlings from immature embryos of interspecific hybrids in Brachiaria.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
8.
Shasany AK Darokar MP Dhawan S Gupta AK Gupta S Shukla AK Patra NK Khanuja SP 《The Journal of heredity》2005,96(5):542-549
Three controlled crosses were carried out involving Mentha arvensis and Mentha spicata [M. spicata CIMAP/C30 x M. spicata CIMAP/C33 (cv. Neera); M. arvensis CIMAP/C18 x CIMAP/C17 (cv. Kalka); and M. arvensis CIMAP/C17 x M. spicata CIMAP/C33]. The parents were subjected to random amplified polymorphic DNA (RAPD) analysis with 80 primers, and polymorphic primers were tested for detecting coinherited RAPD profiles among the progeny of these crosses. Of 50 seedlings tested from each intraspecific cross, all demonstrated dominant profiles with the selected RAPD primers except the detected hybrid from respective crosses. Coinherited markers could be detected with the primers OPJ 01, MAP 06, OPT 08, and OPO 20 for M. arvensis; OPJ 05, OPJ 14, OPO 19, and OPT 09 for M. spicata; and OPJ 07, OPJ 10, OPJ 11, OPJ 14, and OPO 02 for the cross M. arvensis x M. spicata. In our amplified fragment length polymorphism (AFLP) analysis, 40 coinherited marker fragments were identified for the cross involving M. arvensis, 32 for the cross involving M. spicata, and 41 for the interspecific cross between M. arvensis and M. spicata. In all crosses, similarity values between the parents were less than those between the parents and the hybrids. Although RAPD markers are generally considered dominant, it is possible to identify a few codominant markers that behave like restriction fragment length polymorphism (RFLP) markers. This molecular marker system may be helpful in rapidly screening out hybrids in crops where cross-pollination is a problem. 相似文献
9.
G. Barcaccia A. Mazzucato E. Albertini J. Zethof A. Gerats M. Pezzotti M. Falcinelli 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1998,97(1-2):74-82
Gametophytic apomixis in Kentucky bluegrass (Poa pratensis L.) involves the parthenogenetic development of unreduced eggs from aposporic embryo sacs. Attempts to transfer the apomictic
trait beyond natural sexual barriers require further elucidation of its inheritance. Controlled crosses were made between
sexual clones and apomictic genotypes, and the parthenogenetic capacity of (poly)diploid hybrids was ascertained by the auxin
test. A bulked segregant analysis with RAPD and AFLP markers was then used to identify a genetic linkage group related to
the apomictic mode of reproduction. This approach enabled us to detect both an AFLP marker located 6.6 cM from the gene that
putatively controls parthenogenesis and a 15.4-cM genomic window surrounding the target locus. A map of the P. pratensis chromosome region carrying the gene of interest was constructed using additional RAPD and AFLP markers that co-segregated
with the parthenogenesis locus. Highly significant linkage between parthenogenesis and a number of AFLP markers that also
appeared to belong to a tight linkage block strengthens the hypothesis of monogenic inheritance of this trait. If a single
gene is assumed, apomictic polyploid types of P. pratensis would be simplex for a dominant allele that confers parthenogenesis, and this genetic model would be further supported by
the bimodal distribution of the degree of parthenogenesis exhibited in the (poly)diploid progenies from sexual x apomictic
matings. The molecular tagging of apomixis in P. pratensis is an essential step towards marker-assisted breeding and map-based cloning strategies aimed at investigating and manipulating
its mode of reproduction.
Received: 13 January 1998 / Accepted: 19 January 1998 相似文献
10.
Hybrid seedlings from the cross between Nicotiana tabacum, an allotetraploid composed of S and T subgenomes, and N. debneyi die at the cotyledonary stage. This lethality involves programmed cell death (PCD). We carried out reciprocal crosses between
the two progenitors of N. tabacum, N. sylvestris and N. tomentosiformis, and N. debneyi to reveal whether only the S subgenome in N. tabacum is related to hybrid lethality. Hybrid seedlings from reciprocal crosses between N. sylvestris and N. debneyi showed lethal characteristics identical to those from the cross between N. tabacum and N. debneyi. Conversely, hybrid seedlings from reciprocal crosses between N. tomentosiformis and N. debneyi were viable. Furthermore, hallmarks of PCD were observed in hybrid seedlings from the cross N. debneyi × N. sylvestris, but not in hybrid seedlings from the cross N. debneyi × N. tomentosiformis. We also carried out crosses between monosomic lines of N. tabacum lacking the Q chromosome and N. debneyi. Using Q-chromosome-specific DNA markers, hybrid seedlings were divided into two groups, hybrids possessing the Q chromosome
and hybrids lacking the Q chromosome. Hybrids possessing the Q chromosome died with characteristics of PCD. However, hybrids
lacking the Q chromosome were viable and PCD did not occur. From these results, we concluded that the Q chromosome belonging
to the S subgenome of N. tabacum encodes gene(s) leading to hybrid lethality in the cross N. tabacum × N. debneyi. 相似文献
11.
S. Krasnyanski T. M. Ball K. C. Sink 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1998,96(5):683-687
Twenty eight somatic hybrid plants were identified following protoplast fusions between peppermint (Mentha piperita L. cv Black Mitcham), producing high-quality oil, and spearmint (Mentha spicata L. cv Native Spearmint), likewise producing high-quality oil and also possessing resistance to verticillium wilt. Prior to
fusion, peppermint protoplasts were subjected to iodoacetic acid to inhibit cell division. Protoplasts of peppermint and spearmint
were fused using polyethylene glycol plus DMSO. Fusion products were cultured according to an efficient protoplast-to-plant-cycle
protocol developed for peppermint. Using this protocol, iodoacetic acid-treated peppermint protoplasts were not able to divide,
whereas untreated spearmint protoplasts had the ability to produce callus but not shoots. Therefore, selection of somatic
hybrid calli was based on the presumed capability of hybrid cells to form calli and shoots. Shoots in vitro were initially
identified as hybrids using RAPD profiles. Subsequently, observations on morphology, chromosome counts, and Southern-hybridization
patterns confirmed their hybrid status. The results of verticillium tests revealed that 18 somatic hybrids were more susceptible
than Native Spearmint, while hybrid II-14 had a level of susceptibility intermediate between that of the fusion parents. Oil-analysis
of hybrid plants indicated that they all have a GC-profile typical of spearmint oil.
Received: 8 February 1997 / Accepted: 9 April 1997 相似文献
12.
Expression of elements of apomixis was studied for ten seasons in sorghum line AS-1a and its backcross hybrids in the 9E and
A3 sterile cytoplasms. Cytoembryological analysis revealed aposporous embryo sacks (apo-ESs), their initial cells, and, rare,
parthenogeneic proembryos in ovules of line AS-1a and its BC2 and BC3 hybrids on the 9E cytoplasm. The A3 sterile cytoplasm suppressed the development of parthenogenetic proembryos, but did not
affect the apo-ES formation. The frequency of apomictic elements increased in seasons with high daily temperatures and total
precipitation deficiency in the period of ovule and megagametophyte development (r = −0.805, p <.01). Selection was used to isolate the families where the frequency of ovules with apo-ESs was 28% and the frequency of
parthenogenetic proembryos was 14%. Emasculated panicles of line AS-1a were pollinated with pollen of line Volzhskoe-4v, which
carried the Rs marker dominant gene, responsible for the anthocyan color of coleoptyles and leaves in seedlings. Plants of the maternal
type were found in the progenies of these crosses at a frequency of 1.4–28.1%. The genetic structure of the endosperm in grains
with maternal-type seedlings was inferred from the electrophoretic patterns of storage proteins (kafirins). The kafirin spectra
of grains producing maternal-type seedlings was similar to the spectrum of line AS-1a and differed from the spectra of grains
producing hybrid seedlings, indicating that the endosperm developed autonomously when apomictic grains formed in line AS-1a.
The results showed that lines with facultative apomixis can be constructed in functionally diploid plants. 相似文献
13.
Aerides vandarum and Vanda stangeana are two rare and endangered vandaceous orchids with immense floricultural traits. The intergeneric hybrids were synthesized
by performing reciprocal crosses between them. In vitro germination response of the immature hybrid embryos was found to be
best on half-strength Murashige and Skoog medium supplemented with 20% (v/v) coconut water/liquid endosperm from tender coconut. Determination of hybridity was made as early as the immature seeds or
embryos germinated in vitro, using randomly amplified polymorphic DNA (RAPD) markers. Out of 15 arbitrarily chosen decamer
RAPD primers, two were found to be useful in amplification of polymorphic bands specific to the parental species and their
presence in the reciprocal crosses. However, a decisive profile that can identify the reciprocal crosses could not be provided
by RAPD. Amplification of the trnL-F non-coding regions of chloroplast DNA of the parent species and hybrids aided easy identification of the reciprocal crosses
from the fact that maternal inheritance of chloroplast DNA held true for these intergeneric hybrids. Subsequent restriction
digestion of the polymerase chain reaction (PCR) amplified trnL-F non-coding regions of chloroplast DNA also consolidated the finding. Such PCR-based molecular markers could be used for
early determination of hybridity and easy identification of the reciprocal crosses. 相似文献
14.
P. M. Magdalita R. A. Drew S. W. Adkins I. D. Godwin 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1997,95(1-2):224-229
Morphological, molecular and cytological analyses were performed to assess the hybridity of 120 putative interspecific hybrids
of Carica papaya L.×C. cauliflora Jacq. In the putative interspecific hybrids the number of main leaf veins was intermediate between the two parents while
the hermaphrodite flower sex form and the low vigour were distinctive features of these hybrids. Petiole length, stem diameter,
leaf length, leaf width and flower colour were similar to C. papaya, whereas leaf shape, type, serration, venation, petiole hairiness and flower shape were similar to C. cauliflora. Markers generated by the polymerase chain reaction using 72 10-mer primers (random amplified polymorphic DNA) revealed a
high level of polymorphism (64%) between C. papaya and C. cauliflora. Seventeen of these primers yielded reliable and easily scorable polymorphic banding patterns that were further screened
to reveal hybrids. A range of 1–5 RAPD primers consistently confirmed that all 120 plants were genetic hybrids, with all of
them containing at least one band from the male parent. Cytological analysis revealed that 7–48% of the cells in many of the
interspecific hybrids were aneuploid suggesting that chromosome elimination was occurring. The frequency of aneuploid cells
was negatively associated (r=0.88) with the number of bands from the male parent integrated into the hybrid. Pollen fertility of the hybrids was from
0.5 to 14.0% while C. papaya and C. cauliflora had 88.0–99.0% and 90.0–97.0% fertile pollen, respectively.
Received: 28 February 1996 / Accepted: 27 September 1996 相似文献
15.
J. G. Dubouzet K. Shinoda N. Murata 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1998,96(3-4):385-388
Cut flowers of Allium giganteum Regel were emasculated and maintained in half-strength Murashige and Skoog liquid medium supplemented with 3% sucrose and
1000 ppm each of AgrimycinR and BenlateR. Wide hybridization was attempted and, through embryo rescue, putative hybrids were obtained from crosses involving A. cernuum Roth, A. oreophilum C.A. Mey. and A. schubertii Zucc. PCR amplification of the internal transcribed spacer of ribosomal DNA followed by digestion with NdeII generated restriction profiles that confirmed the hybrid nature of the A. giganteum×A. schubertii progenies. The other putative hybrids were found to be products of self pollination.
Received: 15 August 1997 / Accepted: 2 September 1997 相似文献
16.
Mode of reproduction is detected by Parth1 and Sex1 SCAR markers in a wide range of facultative apomictic Kentucky bluegrass varieties 总被引:2,自引:0,他引:2
Albertini Emidio Barcaccia Gianni Porceddu Andrea Sorbolini Silvia Falcinelli Mario 《Molecular breeding : new strategies in plant improvement》2001,7(4):293-300
Gametophytic apomixis in Kentucky bluegrass (Poa pratensis L.) involves the parthenogenetic development of unreduced eggs from aposporic embryo sacs. Marker-assisted selection for the mode of reproduction in P. pratensis would avoid costly and time-consuming phenotypic progeny tests. We developed and tested two SCAR primer pairs that are associated with the mode of reproduction in P. pratensis. The SCAR primers identified the apomictic and sexual genotypes among progenies of sexual x apomictic crosses with very low bias. Furthermore, when tested on a wide range of Italian and exotic P. pratensis germplasm, they were able to unequivocally distinguish sexual from apomictic genotypes. This system should, therefore, allow new selection models to be set up in this species. 相似文献
17.
The effect of maternal, facultatively apomictic plants on population diversity was evaluated in seven hybridizing polyploid Pilosella populations, where apomictic (P. bauhini or P. aurantiaca) and sexual (P. officinarum) biotypes coexist. The ploidy level, reproductive system, morphology, clonal structure and chloroplast DNA haplotypes were used to characterize these plants and their hybrids. The reproductive origins of the progeny were assessed through either a flow cytometric seed screen and/or a comparison between the ploidy level of progeny embryos/seedlings and the maternal ploidy level. The cultivated progeny derived from residual sexuality in maternal apomicts were also identified based on their morphology and reproductive behaviour. The progeny different from their maternal parents (0.6?92.3 % of progeny embryos and 0?100 % of progeny seedlings) originated either sexually or via haploid parthenogenesis. Comparing the facultatively apomictic and sexual mothers, the progeny arrays generated in the field showed that apomictic mothers produce progeny that is more variable in ploidy level. This effect was demonstrated at both the embryonic and seedling stages of progeny development. Residual sexuality in apomicts was also effective in experimental crosses, generating progeny similar to spontaneous hybrids in the field. The 2n + n hybrids produced from an apomictic and a sexual parent displayed similar reproductive behaviour, producing polyhaploid, sexual and apomictic progeny in variable ratios. Repeated hybridizations between parental species and/or multi-step crosses can result in hybrid swarms rich in cytotypes and morphotypes. The variation recorded in these populations suggests prevailing introgressive hybridization towards the sexual species P. officinarum. 相似文献
18.
Anushri Varshney M. Lakshmikumaran P. S. Srivastava Vibha Dhawan 《In vitro cellular & developmental biology. Plant》2001,37(2):227-231
Summary Random amplified polymorphic DNA (RAPD) markers were utilized for screening the clonal fidelity of in vitro-raised bulblets of Lilium sp. (Asiatic hybrids) produced through adventitious mode of propagation. The first set of 14 bulblets was randomly chosen
from about 175 micropropagated bulblets regenerated from 1×1 cm2 bulbscale segments (explants) of cultivar ‘Gran Paradiso’ after four subcultures (after 6 mo.). The second set of 15 bulblets
was selected again randomly after 12 subcultures (after one and a half years) when the bulblets were to be taken out for transplantation.
Of the 20 primers used to screen the samples, only 14 primers gave clear reproducible bands. The 14 primers produced a total
of 163 (an average of 11.6 bands per primer) scorable bands. Analysis of individual primers revealed the RAPD patterns produced
were all shared by both the in vitro-raised bulblets (randomly selected after four and 12 subcultures) and the mother bulb. There was no variation observed within
the tissue culture-raised progenies. Thus, our results show that adventitiously propagated in vitro bulblets of Asiatic hybrids of lilies are clonally uniform and stable. 相似文献
19.
Identification of molecular markers linked to the Yr15 stripe rust resistance gene of wheat originated in wild emmer wheat, Triticum dicoccoides 总被引:11,自引:0,他引:11
G. L. Sun T. Fahima A. B. Korol T. Turpeinen A. Grama Y. I. Ronin E. Nevo 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1997,95(4):622-628
The Yr15 gene of wheat confers resistance to the stripe rust pathogen Puccinia striiformis West., which is one of the most devastating diseases of wheat throughout the world. In the present study, molecular markers
flanking the Yr15 gene of wheat have been identified using the near-isogenic-lines approach. RFLP screening of 76 probe-enzyme combinations
revealed one polymorphic marker (Nor/TaqI) between the susceptible and the resistant lines. In addition, out of 340 RAPD primers tested, six produced polymorphic
RAPD bands between the susceptible and the resistant lines. The genetic linkage of the polymorphic markers was tested on segregating
F2 population (123 plants) derived from crosses between stripe rust-susceptible Triticum durum wheat, cv D447, and a BC3F9 resistant line carrying Yr15 in a D447 background. A 2.8-kb fragment produced by the Nor RFLP probe and a 1420-bp PCR product generated by the RAPD primer OPB13 showed linkage, in coupling, with the Yr15 gene. Employing the standard maximum-likelihood technique it was found that the order OPB13
1420
–Yr15–Nor1 on chromosome 1B appeared to be no less than 1000-times more probable than the closest alternative. The map distances between
OPB13
1420
–Yr15–Nor1 are 27.1 cM and 11.0 cM for the first and second intervals, respectively. The application of marker-assisted selection for
the breeding of new wheat cultivars with the stripe rust resistance gene is discussed.
Received: 27 February 1997/Accepted: 7 March 1997 相似文献
20.
Production and characterization of interspecific hybrids between Brassica maurorum and crop brassicas 总被引:5,自引:0,他引:5
B. Chrungu N. Verma A. Mohanty A. Pradhan K. R. Shivanna 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1999,98(3-4):608-613
Seven interspecific hybrids were produced between Brassica maurorum (♀), a wild species resistant to Alternaria blight and white rust, and all the monogenomic (B. campestris, B. nigra and B. oleracea) and digenomic (B. juncea, B. napus and B. oleracea) crop brassicas (♂) through embryo rescue. The hybrids were confirmed by means of morphological and cytological studies.
All the hybrids were pollen-sterile. Amphidiploids were induced in three of the hybrids: B. maurorum×B. napus, B. maurorum×B. carinata, B. maurorum×B. nigra. The hybrids were also confirmed through DNA analyses for nuclear and organelle genomes using RAPD and RFLP techniques.
Received: 31 July 1998 / Accepted: 14 August 1998 相似文献