Ploidy manipulation and introgression breeding in Darwin hybrid tulips
Marasek-Ciolakowska, A. ; Xie, S.L. ; Arens, P. ; Tuyl, J.M. van - \ 2014
Euphytica 198 (2014)3. - ISSN 0014-2336 - p. 389 - 400.
asiatic lilies lilium - gish analysis - sexual polyploidization - interspecific hybrids - garden tulips - genome - recombination - gesneriana - hybridization - fosteriana
Meiotic polyploidisation via crossing with 2n gamete producing genotypes and interploidy crosses are two of the main methods currently used to obtain polyploid tulips. In our study diploid 2n gamete producing F-1 hybrids of Darwin hybrids (Tulipa gesneriana x Tulipa fosteriana) and triploid hybrid resulting from 'Rhodos' x 'Princeps' cross were used as pollen donor and crossed with cultivars of T. gesneriana in the following combination: 2x x 2x, 3x x 2x, 2x x 3x, and 3x x 3x. The progenies resulting from crosses at diploid level were mostly diploid, whereas a few seedlings were triploid. In 3x x 2x crosses aneuploids with chromosome constitution in between triploid and tetraploid (43-45 chromosomes) were predominant, but also one tetraploid (2n = 4x = 48) and four pentaploids (2n = 5x = 60) were obtained. In 2x x 3x crosses most progenies were triploid with the exception of a few aneuploids (3x + 1 and 3x - 1), whereas in 3x x 3x cross diploid and aneuploid genotypes were recorded with chromosome number varied from 27 to 34. These results indicate that triploid parents produced aneuploid as well as euploid (x, 2x, 3x) gametes and that success in ploidy manipulation in tulip depends to a large degree on the ploidy level of the parental genotypes used for hybridization. Genome constitution of selected population of F1 and BC1 hybrids was analyzed through genomic in situ hybridization (GISH). GISH analysis of the BC1 showed a considerable amount of intergenomic recombination which is desirable for introgression breeding.
Potential for analytic breeding in allopolyploids: An illustration from Longiflorum x Asiatic hybrid lilies (Lilium).
Nadeem Khan, M. ; Zhou, Shujun ; Ramanna, M.S. ; Arens, P.F.P. ; Herrera, Jeronimo ; Visser, R.G.F. ; Tuyl, J.M. van - \ 2009
Euphytica 166 (2009)3. - ISSN 0014-2336 - p. 399 - 409.
sexual polyploidization - interspecific hybrids - lolium-multiflorum - festuca-pratensis - bc2 progenies - gish analysis - lily hybrids - sweet-potato - 2n pollen - genome
Ploidy level and intergenomic recombination was studied in interspecific hybrids between Longiflorum × Asiatic lilies (LA hybrid) backcross to Asiatic parents in order to assess the possibility for analytic breeding in lily. By backcrossing the diploid (2n = 2x = 24) F1 interspecific hybrid between Longiflorum × Asiatic lilies to Asiatic parents, 104 BC1 progeny plants were produced. Among these, there were 27 diploids, 73 triploids (2n = 2x = 36) and 4 aneuploids (2x ¿ 1, 2x + 2 or 2x + 3). In addition, by backcrossing triploid BC1 (LAA) plants to diploid Asiatic parents in 2x ¿ 3x and reciprocal combinations, 14 diploid BC2 progenies were produced. Genomic in situ hybridization (GISH) was performed to study the intergenomic recombination and karyotype composition. GISH indicated extensive intergenomic recombination among the chromosomes in LA hybrids. A large number of Longiflorum chromosomes were transmitted to the BC1 progenies from LA hybrids. However, very few Longiflorum chromosomes were transmitted from the BC1 triploid (LAA) plants to the BC2 progenies. The occurrence of diploid plants in the BC progenies of LA hybrids has opened the prospects of analytic breeding in lilies. In this approach, the selection of superior genotypes can be carried out at the diploid level and polyploid forms are synthesized from superior diploid parents. The advantages of analytic breeding are evident: (a) a maximum level of heterozygosity can be attained in the synthetic polyploids and (b) introgression can be achieved with a minimum of linkage drag. Based on GISH results the potential application of analytic breeding in lily allopolyploids has been discussed
Construction of chromosomal recombination maps of three genomes of lilies (Lilium) based on GISH analysis.
Nadeem Khan, M. ; Shujun Zhou, ; Barba Gonzalez, R. ; Ramanna, M.S. ; Visser, R.G.F. ; Tuyl, J.M. van - \ 2009
Genome 52 (2009)3. - ISSN 0831-2796 - p. 238 - 251.
in-situ hybridization - genetic-linkage maps - nuclear-dna amounts - x asiatic hybrids - translocation breakpoints - intergenomic recombination - homoeologous recombination - sexual polyploidization - interspecific hybrids - arabidopsis-thaliana
Chromosomal recombination maps were constructed for three genomes of lily (Lilium) using GISH analyses. For this purpose, the backcross (BC) progenies of two diploid (2n = 2x = 24) interspecific hybrids of lily, viz. Longiflorum × Asiatic (LA) and Oriental × Asiatic (OA), were used. Mostly the BC progenies of LA hybrids consisted of both triploid (2n = 3x = 36) and diploid (2n = 2x = 24) with some aneuploid genotypes and those of OA hybrids consisted of triploid (2n = 3x = 36) and some aneuploid genotypes. In all cases, it was possible to identify the homoeologous recombinant chromosomes as well as accurately count the number of crossover points, which are called ¿recombination sites¿. Recombination sites were estimated in the BC progeny of 71 LA and 41 OA genotypes. In the case of BC progenies of LA hybrids, 248 recombination sites were cytologically localized on 12 different chromosomes of each genome (i.e., L and A). Similarly, 116 recombinant sites were localized on the 12 chromosomes each from the BC progenies of OA hybrids (O and A genomes). Cytological maps were constructed on the basis of the percentages of distances (micrometres) of the recombination sites from the centromeres. Since an Asiatic parent was involved in both hybrids, viz. LA and OA, two maps were constructed for the A genome that were indicated as Asiatic (L) and Asiatic (O). The other two maps were Longiflorum (A) and Oriental (A). Remarkably, the recombination sites were highly unevenly distributed among the different chromosomes of all four maps. Because the recombination sites can be unequivocally identified through GISH, they serve as reliable landmarks and pave the way for assigning molecular markers or desirable genes to chromosomes of Lilium and also monitor introgression of alien segments
Analysis of the meiosis in the F-1 hybrids of Longiflorum x Asiatic (LA) of lilies (Lilium) using genomic in situ hybridization
Zhou, S.J. ; Ramanna, M.S. ; Visser, R.G.F. ; Tuyl, J.M. van - \ 2008
Journal of Genetics and Genomics 35 (2008)11. - ISSN 1673-8527 - p. 687 - 695.
intergenomic recombination - interspecific hybrids - parental genomes - allium-roylei - bc2 progenies - lily hybrids - gish - chromosomes - fistulosum - identification
Longiflorum and Asiatic lilies of the genus Lilium of the family Liliaceae are two important groups of modem lily cultivars. One of the main trends of lily breeding is to realize introgression between these groups. With cut style pollination and embryo rescue, distant hybrids between the two groups have been obtained. However, the F-1 hybrids are highly sterile or some of them could produce a small number of 2n gametes, and their BC1 progenies are usually triploids. Dutch lily breeders have selected many cultivars from these BC1 progenies based on their variation. It is presumably suggested that such variation could be caused by intergenomic recombination and abnormal meiosis during gamete formation in F-1 hybrids of Longiflorum, x Asiatic (LA) hybrids in Lilium. Therefore, the meiotic process of ten F-1 LA hybrids was cytologically investigated using genomic in situ hybridization and traditional cytological methods in the present research. The results showed that: at metaphase I, the homoeologous chromosome pairing among different F-1 hybrids ranged from 2.0 to 11.4 bivalents formed by homoeologous chromosomes per pollen mother cell (PMC), and very few multivalents, and even very few bivalents were formed by two chromosomes within one genome rather than homoeologous chromosomes in some PMCs; at anaphase I, all bivalents were disjoined and most univalents were divided. Both the disjoined bivalents (half-bivalents) and the divided univalents (sister chromatids) moved to the opposite poles, and then formed two groups of chromosomes; because the two resulting half-bivalents retained their axes in the cell undisturbed, many crossover types, including single crossovers, three strand double crossovers, four strand double crossovers, four strand triple crossovers, and four strand multiple crossovers between the non-sister chromatids in the tetrads of bivalents, were clearly inferred by analyzing the breakpoints on the disjoined bivalents. The present investigation not only explained the reason for sterility of the F-1 LA hybrids and the variation of their BC1 progenies, but also provided a new method to analyze crossover types in other F-1 interspecific hybrids as well.
Genome composition of triploid lily cultivars derived from sexual polyploidization of Longiflorum x Asiatic hybrids (Lilium)
Shujun Zhou, ; Ramanna, M.S. ; Visser, R.G.F. ; Tuyl, J.M. van - \ 2008
Euphytica 160 (2008)2. - ISSN 0014-2336 - p. 207 - 215.
in-situ hybridization - interspecific hybrids - aegilops-squarrosa - alstroemeria - gish - recombination - introgression - restitution - mechanisms - progenies
About 19 cultivars, which had originated from backcrosses between F1 LA (Longiflorum × Asiatic) hybrids (2n = 2x = 24) as female parents and Asiatic cultivars as male parents (2n = 2x = 24), were analyzed with genomic in situ hybridization. 17 of them were triploid (2n = 3x = 36), and two aneuploid (2n = 3x + 1 = 37). The triploid cultivars had resulted from the functional 2n eggs produced by the female parents (F1 hybrids) because first division restitution (FDR) occurred in their meiosis during megasporogenesis. Similarly, the aneuploid cultivars had originated from viable 2n + 1 eggs. The extra chromosome in cultivar 041555 or 041572 resulted from one univalent or one half-bivalent which might have lagged behind when the sister chromatids of the other univalents and half-bivalents were segregating during the FDR process in their LA hybrid parents, respectively. That the majority of cultivars possessed recombinant chromosomes showed that intergenomic recombination might play an important role during the selection of the cultivars directly from BC1 progenies. That five cultivars of the 15 recombinant cultivars only had reciprocal recombinant chromosomes and 10 cultivars had non-reciprocal recombinant chromosomes indicates that the latter are more important. Because 9 of the 10 non-reciprocal recombinant cultivars possessed substitutions for recombinant segments, it also indicated that such substitutions could be an important source for the genetic variation in the sexual triploid BC1 progenies. In such cases there was a potential for the expression of the recessive genes of the backcross parent in a nulliplex (aaa) condition in the substituted segments. Genetic variation resulting from such nulliplex loci might have played a role in the selection of some of the cultivars.
Nitrous oxide N2O incudes 2n gametes in sterile F1 hybrids of Oriental x Asiatic lilies (Lilium) and leads to intergenomic recombination
Barba Gonzalez, R. ; Miller, C.T. ; Ramanna, M.S. ; Tuyl, J.M. van - \ 2006
Euphytica 148 (2006)3. - ISSN 0014-2336 - p. 303 - 309.
in-situ hybridization - sexual polyploidization - interspecific hybrids - aneuploids - gish
Eight different genotypes of the F1 hybrids between Oriental × Asiatic lily (Lilium) hybrids (2n = 2x = 24) were treated with nitrous oxide (N2O) gas under pressure for 24 and 48 hours. At the time of treatment, all plants possessed early meiotic stages in the anthers of the oldest flower buds. The mature flowers from treated plants were monitored for fertility through pollen germination in vitro as well as by using them in crosses with diploid Asiatic hybrids (2n = 2x = 24) both as male and female parents. In five out of the eight genotypes of OA hybrids there was evidence for the production of 2n pollen which germinated in vitro from either one or both treatments. The 2n pollen from three genotypes was successfully used in crosses. In two cases, the treated plants were successfully used as female parents which indicated the formation of 2n (or 2x) egg cells. From an analysis of 41 sexual polyploid progenies obtained from N2O treated plants it was shown that they were all euploids consisting of 34 triploids (2n = 3x = 36) and seven tetraploids (2n = 4x = 48). A detailed cytological analysis of 12 progeny plants through genomic in situ hybridization (GISH) proved that N2O had induced first division restitution gametes in most cases and in two cases they produced gametes through indeterminate meiotic restitution. There was evidence for intergenomic recombination in three cases.
Occurrence of 2n gametes in the F1 hybrids of Oriental x Asiatic lilies (Lilium): Relevance to intergenomic recombination and backcrossing
Barba Gonzalez, R. ; Lim, K.B. ; Ramanna, M.S. ; Visser, R.G.F. ; Tuyl, J.M. van - \ 2005
Euphytica 143 (2005)1-2. - ISSN 0014-2336 - p. 67 - 73.
in-situ hybridization - aegilops-squarrosa - sexual polyploidization - interspecific hybrids - restitution - mechanisms - crosses - gish - rye
Cytological modes of the origin of 2n gametes were investigated in six different genotypes of F1 hybrids between Oriental and Asiatic (OA) lilies (Lilium, 2n = 2x = 24). Chromosome pairing between the parental genomes was very low, the average frequency range from 0.3 to 1.2 bivalents per cell among the genotypes. Within a genotype the frequency of bivalents varied from 0 to 6 in some cases. The normally occurring haploid pollen grains were totally sterile. In contrast, in different genotypes, variable percentages of 2n pollen were found and shown to be fertile as estimated from pollen germination. A cytological analysis of Metaphase I and subsequent stages of meiosis using genomic in situ hybridization (GISH) revealed that there was intergenomic recombination between the alien genomes. Following Metaphase I stage, three different types of abnormal cytological events led to the formation of 2n pollen: (i) Post-Metaphase I division (PMI), (ii) Post-Metaphase II division (PMII) and (iii) Asymmetric Cytokinesis of the pollen mother cell followed by chromosome division. All three cytological events led to first division restitution (FDR) gametes. Based on in vitro pollen germination it was proved for two genotypes that 2n pollen was viable only during the first day of anthesis. It was possible to use 2n pollen successfully for backcrossing. Implications of 2n pollen for intergenomic recombination in BC1 progenies are discussed
Occurrence of SDR 2N-gametes in Lilium hybrids
Lim, K.B. ; Shen, T.M. ; Barba Gonzalez, R. ; Ramanna, M.S. ; Tuyl, J.M. van - \ 2004
Breeding Science 54 (2004)1. - ISSN 1344-7610 - p. 13 - 18.
interspecific hybrids - bc2 progenies - potato - mutants - desynapsis - fertility - crosses - pollen - gish
The mechanism of SDR 2n-pollen formation was analyzed in two intra-sectional diploid (2n = 2x = 24) Lilium hybrids (Enchantment x L. pumilum). Variable frequencies of 2n-pollen were found. Meiotic analysis indicated that the intra-sectional hybrids showed perfect chromosome pairing in most cases at metaphase I and normal anaphase I movement of pollen mother cells (PMCs), but produced 2n-pollen by second division restitution (SDR). A high bivalent formation (11.9II and 11.8II, respectively) at metaphase 1, irregular meiotic division such as unbalanced chromosome separation and chromatic fragmentation resulted yet in acceptable pollen fertility for cross-pollination. The hybrids were fertile, and when used as male parents, offspring could tie generated. The significance of the occurrence of 2n-pollen for the breeding of lilies was analyzed.
Genetic control of resistance to soft rot caused by Erwinia carotovora subsp carotovora in Zantedeschia spp. (Araceae), section Aestivae
Snijder, R.C. ; Lindhout, W.H. ; Tuyl, J.M. van - \ 2004
Euphytica 136 (2004)3. - ISSN 0014-2336 - p. 319 - 325.
plastome-genome incompatibility - interspecific hybrids - calla - inheritance - irrigation - tubers
The pattern of heredity of resistance to Erwinia carotovora subsp. carotovora in Zantedeschia spp. is investigated. Four species with different resistance levels (Z. albomaculata, Z. elliotiana, Z. pentlandii, Z. rehmannii) were compared to their reciprocal offspring. The occurrence of plastome-genome incompatibility (PGI) affected plant resistance in all families. Therefore, plants that suffered from PGI were omitted from genetic analyses. Resistance was quantitative and the correlation between resistance levels of parents and offspring (h(2) = 0.33; r(2) = 0.66) indicated a genetic basis of resistance. Z. rehmannii and Z. albomaculata contributed more resistance genes than Z. elliotiana or Z. pentlandii. Transgression among some of the offspring of Z. rehmannii and Z. albomaculata indicated the presence of complementary resistance genes in these two species and good potential for resistance breeding.
Use of 2n gametes for the production of sexual polyploids from sterile Oriental x Asiatic hybrids of lilies (Lilium)
Barba Gonzalez, R. ; Lokker, A.C. ; Lim Ki-Byung, ; Ramanna, M.S. ; Tuyl, J.M. van - \ 2004
Theoretical and Applied Genetics 109 (2004)6. - ISSN 0040-5752 - p. 1125 - 1132.
situ hybridization gish - interspecific hybrids - homoeologous recombination - aegilops-squarrosa - bc2 progenies - alstroemeria - crosses - culture - restitution - chromosomes
Sixteen Oriental and 12 Asiatic cultivars were crossed in 158 different combinations. A total of 708 F1 hybrids were obtained from 86 of the different combinations of 15 Oriental and 11 Asiatic cultivars. Because the Lilium cultivars (2n=2x=24) used for the production of these hybrids belong to two different taxonomic sections-Archelirion (O) and Sinomartagon (A), respectively - the F1 hybrids (OA) could be obtained only through embryo, embryo sac rescue, ovary slice or ovule culture. Most of the F1 hybrids were highly sterile (did not produce viable n gametes) due to the failure of chromosome pairing. However, in a few cases F1 plants were found that produced viable 2n pollen at variable frequencies. These 2n pollen grains were successfully used for the production of backcross progenies. Using genomic in situ hybridization we found intergenomic recombinant chromosomes in the sexual polyploid progenies. These results indicate that there are effective prospects for combining important horticultural traits from the two main groups of cultivars of lilies through sexual polyploidization
Characterisation of distant Alstroemeria hybrids: application of highly repetitive DNA sequences from A. ligtu spp. ligtu
Shujun Zhou, ; Jeu, M.J. de; Visser, R.G.F. ; Kuipers, A.G.J. - \ 2003
Annals of Applied Biology 142 (2003)3. - ISSN 0003-4746 - p. 277 - 283.
in-situ hybridization - molecular cytogenetics - interspecific hybrids - physical organization - ovule culture - sequences - heterochromatin - localization - family - aurea
Clones from a Sau3A family of eight highly repetitive sequences previously isolated from a genomic DNA library of Alstroemeria ligtu ssp. ligtu were sequenced and found to be highly conserved. A trinucleotide microsatellite repeat [GCA](3-4) was present. A second, unrelated, Sau3A repeat was also characterised. Southern analysis proved that the isolated repeats were specific for the A. ligtu subspecies and could not be detected in other Chilean or Brazilean Alstroemeria species. As shown by in situ hybridisation, the Sau3A family and the unrelated Sau3A repeat co-localised at distinct sites along most chromosomes of Alstroemeria ligtu ssp. ligtu and Alstroemeria ligtu ssp. simsii. The present set of species-specific repetitive sequences enables the identification of A. ligtu chromosomes, and thus the tracking of chromosome transmission to interspecific hybrids and their progeny.