scholarly journals Identification of the High Frequency of Triploid Potato Resulting from Tetraploid × Diploid Crosses

HortScience ◽  
2019 ◽  
Vol 54 (7) ◽  
pp. 1159-1163
Author(s):  
Ryan C. Graebner ◽  
Hsuan Chen ◽  
Ryan N. Contreras ◽  
Kathleen G. Haynes ◽  
Vidyasagar Sathuvalli
Keyword(s):  
High Frequency ◽  
Potato Breeding ◽  
Unreduced Gametes ◽  
Hybrid Population ◽  
Development Programs ◽  
Diploid Hybrid ◽  
Diploid Parent ◽  
Genomic Studies ◽  
Triploid Block ◽  
Triploid Clones

Conventional wisdom regarding potato breeding indicates that a strong triploid block prevents the development of viable triploid seeds from crosses between tetraploid and diploid clones. However, in a recent set of crosses between elite tetraploid potatoes and an improved diploid hybrid population derived from group Stenotomum and group Phureja, 61.5% of the resulting clones were found to be triploid. If clones derived from one diploid parent suspected of producing a high frequency of unreduced gametes were excluded, then the frequency of triploid clones increased to 74.4%. Tubers of these triploids are generally intermediates of the two parental groups. Our findings indicate the possibility of using triploid potatoes in potato variety development programs and in genetic and genomic studies.

scholarly journals A nonS-locus F-box gene breaks self-incompatibility in diploid potatoes

2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Ling Ma ◽  
Chunzhi Zhang ◽  
Bo Zhang ◽  
Fei Tang ◽  
Futing Li ◽  
...  
Keyword(s):  
Potato Breeding ◽  
Inbred Lines ◽  
Hybrid Breeding ◽  
Self Incompatibility ◽  
Diploid Hybrid ◽  
Food Crop ◽  
Global Food Security ◽  
The Third ◽  
Self Compatibility ◽  
Global Food

AbstractPotato is the third most important staple food crop. To address challenges associated with global food security, a hybrid potato breeding system, aimed at converting potato from a tuber-propagated tetraploid crop into a seed-propagated diploid crop through crossing inbred lines, is under development. However, given that most diploid potatoes are self-incompatible, this represents a major obstacle which needs to be addressed in order to develop inbred lines. Here, we report on a self-compatible diploid potato, RH89-039-16 (RH), which can efficiently induce a mating transition from self-incompatibility to self-compatibility, when crossed to self-incompatible lines. We identify the S-locusinhibitor (Sli) gene in RH, capable of interacting with multiple allelic variants of the pistil-specific S-ribonucleases (S-RNases). Further, Sli gene functions like a general S-RNase inhibitor, to impart SC to RH and other self-incompatible potatoes. Discovery of Sli now offers a path forward for the diploid hybrid breeding program.

scholarly journals Cell fusion as the formation mechanism of unreduced gametes in the gynogenetic diploid hybrid fish

2016 ◽  
Vol 6 (1) ◽  
Author(s):  
Jing Wang ◽  
Qingfeng Liu ◽  
Kaikun Luo ◽  
Xuan Chen ◽  
Jun Xiao ◽  
...  
Keyword(s):  
Cell Fusion ◽  
Formation Mechanism ◽  
Unreduced Gametes ◽  
Diploid Hybrid ◽  
Gynogenetic Diploid ◽  
Hybrid Fish

Mitotic and meiotic irregularities in somatic hybrids of Lycopersicon esculentum and Solanum tuberosum

Genome ◽  
1994 ◽  
Vol 37 (5) ◽  
pp. 726-735 ◽  
Author(s):  
A. M. A. Wolters ◽  
H. C. H. Schoenmakers ◽  
S. Kamstra ◽  
J. van Eden ◽  
M. Koornneef ◽  
...  
Keyword(s):  
In Situ Hybridization ◽  
High Frequency ◽  
Somatic Hybrids ◽  
Unreduced Gametes ◽  
Root Tip ◽  
Root Tips ◽  
Tetrad Stage ◽  
Chromosome Arm ◽  
Mother Cells

Chromosome numbers were determined in metaphase complements of root-tip meristems of 107 tomato (+) potato somatic hybrids, obtained from five different combinations of parental genotypes. Of these hybrids 79% were aneuploid, lacking one or two chromosomes in most cases. All four hybrids that were studied at mitotic anaphase of root tips showed laggards and bridges, the three aneuploids in a higher frequency than the single euploid. Hybrid K2H2-1C, which showed the highest percentage of aberrant anaphases, possessed 46 chromosomes. Fluorescence in situ hybridization with total genomic DNA showed that this hybrid contained 23 tomato, 22 potato, and 1 recombinant chromosome consisting of a tomato chromosome arm and a potato chromosome arm. The potato parent of K2H2-1C was aneusomatic in its root tips with a high frequency of monosomic and trisomic cells and a relatively high frequency of cells with one fragment or telosome. Meiotic analyses of three tomato (+) potato somatic hybrids revealed laggards, which occurred most frequently in the triploid hybrids, and bridges, which were frequently present in pollen mother cells (PMCs) at anaphase I of hypotetraploid K2H2-1C. We observed putative trivalents in PMCs at diakinesis and metaphase I of eutriploid A7-82A and quadrivalents in part of the PMCs of hypotetraploid K2H2-1C, suggesting that homoeologous recombination between tomato and potato chromosomes occurred in these hybrids. All three hybrids showed a high percentage of first division restitution, giving rise to unreduced gametes. However, shortly after the tetrad stage all microspores completely degenerated, resulting in exclusively sterile pollen.Key words: tomato, potato, symmetric somatic hybrids, chromosomal irregularities, genomic in situ hybridization.

scholarly journals DIPLOID HETEROZYGOUS HYBRIDS FROM MATINGS BETWEEN ESCHERICHIA COLI AND SALMONELLA TYPHOSA

1960 ◽  
Vol 112 (2) ◽  
pp. 361-372 ◽  
Author(s):  
L. S. Baron ◽  
Walter M. Spilman ◽  
Warren F. Carey
Keyword(s):  
High Frequency ◽  
Carbon Sources ◽  
Low Frequency ◽  
Diploid Hybrid ◽  
Hybrid Form ◽  
Biochemical Characteristics ◽  
Cultural Form ◽  
E Coli ◽  
Unstable Type ◽  
K 12

An Hfr strain of E. coli K-12 has been shown to mate at low frequency with a number of strains of S. typhosa. The hybrids, selected as lactose positives, retained all other antigenic and biochemical manifestations of the S. typhosa parent. A Lac+ hybrid, S. typhosa strain 643L+ was remated with the E. coli Hfr and plated on minimal media containing L-arabinose, D-xylose, L-rhamnose, or L-fucose as the sole carbon sources. Hybrids of the remated strain appeared at high frequency on the plates containing L-arabinose, and could be detected at lower frequencies on plates containing D-xylose, L-rhamnose, and L-fucose. Those selected for D-xylose or L-rhamnose utilization possessed the attributes of segregating diploid heterozygotes being highly unstable and continually segregating a cultural form typical of the S. typhosa parent. The unstable type exhibited most of the biochemical characteristics of the E. coli parent including the ability to produce indol, and also reacted with antiserum to both the E. coli and S. typhosa parent strains, owing to the acquisition of a thermolabile antigen from the E. coli parent. The parent and hybrid strains were examined in detail for changes in patterns of phage susceptibility and virulence. Acquisition of susceptibility to a number of the T phages, a characteristic of the E. coli parent, was observed in one of the hybrid types. A decrease in virulence of the diploid hybrid form of S. typhosa in the mouse virulence test was found.

MULTIVARIATE ANALYSES OF POTATO HYBRIDS. I. DISCRIMINATION BETWEEN TETRAPLOID-DIPLOID HYBRID FAMILIES AND THEIR RELATIONSHIP TO CULTIVARS

1980 ◽  
Vol 22 (2) ◽  
pp. 227-235 ◽  
Author(s):  
G. C. C. Tai ◽  
H. De Jong
Keyword(s):  
Potato Breeding ◽  
Multivariate Analyses ◽  
Field Trials ◽  
Canonical Analysis ◽  
Diploid Hybrid ◽  
Horticultural Traits ◽  
Mean Vectors ◽  
Group Tuberosum ◽  
Substantial Distance

Clones of ten 4x-2x hybrid families were obtained by crossing five Group Tuberosum parents with each of two (Group Phureja × haploid Group Tuberosum) parents. The performances of horticultural traits of the 4x-2x progenies were distinctly different from those of the 4x parents and cultivars. Multivariate analyses of eight traits were performed on data of each of the three field trials in 1976, 1977 and 1978 and on the means of clones over the three years. Multivariate analyses of variance indicated significant differences between mean vectors of the 4x-2x families. Canonical analysis based on means of clones revealed clearly the effects of 4x and 2x parents on the distributions of the 4x-2x families. However, analysis of canonical distances between the hybrid families also suggested the possible existence of interactions of 4x and 2x parents. Substantial distance was observed between the 4x-2x families and the 4x parents and cultivars. The results lead to a discussion on future strategies of using the 4x-2x hybrids in potato breeding.

scholarly journals Community Development, Local Wisdoms, and Ineffective Government Aid: The Case of Lombok Post-Disaster House Reconstruction Project

2021 ◽  
Vol 2 (2) ◽  
pp. 136
Author(s):  
Mira Ardhya Paramastri
Keyword(s):  
Community Development ◽  
High Frequency ◽  
Development Projects ◽  
Careful Attention ◽  
Development Programs ◽  
Disaster Victims ◽  
Government Aid ◽  
Local Potentials ◽  
Reconstruction Project ◽  
Post Disaster

Despite the high frequency of disasters, post-disaster development projects in Indonesia have yet been implemented effectively. Such may not be easily reflected through the number of aid projects given, for the reality is much more complex. This article believes that the significance of development projects should be assessed from the aid recipients' perspective. The excess rebuilding back in Aceh's 2004 post-disaster case is one example that shows the importance of paying attention to recipient needs from their perspective rather than aid giver perceptions. The post-disaster condition in Lombok back in 2018 could serve as an example to show the effectiveness of post-disaster development in Indonesia recently. In accordance, this article aims to show how the post-disaster community development programs implemented by multi-stakeholders in Indonesia, especially government-initiated ones, have yet successfully fulfilled Lombok post-disaster victims' needs. The article also found that active initiation from the locals and careful attention to local potentials and wisdom is crucial to determine post-disaster development's success. Such a conclusion is based on the assessment of whether the programs have fulfilled community development principles, in addition to satisfying the victim's human security.

scholarly journals Asynapsis and unreduced gamete formation in a Trifolium interspecific hybrid

2022 ◽  
Vol 22 (1) ◽  
Author(s):  
Helal A. Ansari ◽  
Nicholas W. Ellison ◽  
Isabelle M. Verry ◽  
Warren M. Williams
Keyword(s):  
Meiotic Division ◽  
High Frequency ◽  
Molecular Mechanisms ◽  
Intergeneric Hybrids ◽  
Unreduced Gametes ◽  
Unreduced Gamete ◽  
Sister Chromatids ◽  
Gamete Formation ◽  
Normal Meiosis ◽  
Metaphase I

Abstract Background Unreduced gametes, a driving force in the widespread polyploidization and speciation of flowering plants, occur relatively frequently in interspecific or intergeneric hybrids. Studies of the mechanisms leading to 2n gamete formation, mainly in the wheat tribe Triticeae have shown that unreductional meiosis is often associated with chromosome asynapsis during the first meiotic division. The present study explored the mechanisms of meiotic nonreduction leading to functional unreduced gametes in an interspecific Trifolium (clover) hybrid with three sub-genomes from T. ambiguum and one sub-genome from T. occidentale. Results Unreductional meiosis leading to 2n gametes occurred when there was a high frequency of asynapsis during the first meiotic division. In this hybrid, approximately 39% of chromosomes were unpaired at metaphase I. Within the same cell at anaphase I, sister chromatids of univalents underwent precocious separation and formed laggard chromatids whereas paired chromosomes segregated without separation of sister chromatids as in normal meiosis. This asynchrony was frequently accompanied by incomplete or no movement of chromosomes toward the poles and restitution leading to unreduced chromosome constitutions. Reductional meiosis was restored in progeny where asynapsis frequencies were low. Two progeny plants with approximately 5 and 7% of unpaired chromosomes at metaphase I showed full restoration of reductional meiosis. Conclusions The study revealed that formation of 2n gametes occurred when asynapsis (univalent) frequency at meiosis I was high, and that normal gamete production was restored in the next generation when asynapsis frequencies were low. Asynapsis-dependent 2n gamete formation, previously supported by evidence largely from wheat and its relatives and grasshopper, is also applicable to hybrids from the dicotyledonous plant genus Trifolium. The present results align well with those from these widely divergent organisms and strongly suggest common molecular mechanisms involved in unreduced gamete formation.

scholarly journals Little heterosis found in Diploid Hybrid Potato

2021 ◽  
Author(s):  
James Randall Adams ◽  
Chaozhi Zheng ◽  
Michiel E. de Vries ◽  
Fred A. van Eeuwijk
Keyword(s):  
Complex Traits ◽  
Potato Breeding ◽  
Diallel Analysis ◽  
Hybrid Breeding ◽  
Target Market ◽  
Hybrid Vigour ◽  
Diploid Hybrid ◽  
Genetic Components ◽  
Deleterious Alleles ◽  
Highly Correlated

Hybrid potato breeding has become a novel alternative to conventional potato breeding allowing breeders to overcome intractable barriers (e.g. tetrasomic inheritance, masked deleterious alleles, obligate clonal propagation) with the benefit of seed-based propagule, flexible population design, and the potential of hybrid vigour. Until now, however, no formal inquiry has adequately examined the relevant genetic components for complex traits in hybrid potato populations. In this present study, we use a two-step modelling approach to estimate the relevant variance components to assess the magnitude of the general and specific combining abilities (GCA and SCA, respectively) in diploid hybrid potato (DHP). SCA effects were identified for all yield components studied here warranting evidence of non-additive genetic effects in hybrid potato yield. However, the estimated GCA effects were on average two times larger than their respective SCA quantile across all yield phenotypes. Tuber number GCAs and SCAs were found to be highly correlated with total yield's genetic components. Tuber volume appearing under-selected in this population. The prominence of additive effects found for all traits presents evidence that breeders can perform hybrid potato evaluation using the mid-parent value alone. Heterotic vigour stands be useful in bolstering simpler traits but this will be very dependent on the target market of a population. This study represents the first diallel analysis of its kind in diploid potato using material derived from a commercial hybrid breeding programme.

scholarly journals Convergent evolution of polyploid genomes from across the eukaryotic tree of life

2021 ◽  
Author(s):  
Yue Hao ◽  
Jonathon Fleming ◽  
Joanna Petterson ◽  
Eric Lyons ◽  
Patrick P. Edger ◽  
...  
Keyword(s):  
High Frequency ◽  
Gene Loss ◽  
Relative Rate ◽  
Duplicate Gene ◽  
Single Copy ◽  
Selective Constraint ◽  
Diploid Hybrid ◽  
Hybrid Species ◽  
Evolutionary Forces ◽  
Modern Species

By modeling the homoeologous gene losses that occurred in fifty genomes deriving from ten distinct polyploidy events, we show that the evolutionary forces acting on polyploids are remarkably similar, regardless of whether they occur in flowering plants, ciliates, fishes or yeasts. The models suggest these events were nearly all allopolyploidies, with two distinct progenitors contributing to the modern species. We show that many of the events show a relative rate of duplicate gene loss prior to the first post-polyploidy speciation that is significantly higher than in later phases of their evolution. The relatively low selective constraint seen for the single-copy genes these losses produced lead us to suggest that most of the purely selectively neutral duplicate gene losses occur in the immediate post-polyploid period. We also find ongoing and extensive reciprocal gene losses (RGL; alternative losses of duplicated ancestral genes) between these genomes. With the exception of a handful of closely related taxa, all of these polyploid organisms are separated from each other by tens to thousands of reciprocal gene losses. As a result, it is very unlikely that viable diploid hybrid species could form between these taxa, since matings between such hybrids would tend to produce offspring lacking essential genes. It is therefore possible that the relatively high frequency of recurrent polyploidies in some lineages may be due to the ability of new polyploidies to bypass RGL barriers.

Sign in / Sign up

Export Citation Format

Share Document