scholarly journals Substitution Mapping of a Locus Responsible for Hybrid Breakdown in Populations Derived From Interspecific Introgression Line

2021 ◽  
Vol 12 ◽  
Author(s):  
Nilsa Emilia Munguambe ◽  
Shouta Inoue ◽  
Zita Demeter ◽  
Yoshiyuki Yamagata ◽  
Hideshi Yasui ◽  
...  
Keyword(s):  
Genetic Basis ◽  
Interspecific Cross ◽  
Introgression Line ◽  
Chromosome 4 ◽  
Hybrid Breakdown ◽  
Cultivated Rice ◽  
Lod Score ◽  
Interspecific Introgression ◽  
Oryza Meridionalis ◽  
Weak Growth

Hybrid breakdown, a form of postzygotic reproductive barrier, has been reported to hinder gene flow in many crosses between wild and cultivated rice. Here, the phenomenon of hybrid breakdown was observed as low-tillering (i.e., low tiller number) in some progeny of an interspecific cross produced in an attempt to introduce Oryza meridionalis Ng (W1625) chromosomal segments into Oryza sativa L. ssp. japonica “Taichung 65” (T65). Low-tillering lines were obtained in BC4-derived progeny from a cross between W1625 and “Taichung 65,” but the locus for low-tillering could not be mapped in segregating populations. As a second approach to map the locus for low-tillering, we analyzed an F2 population derived from a cross between the low-tillering lines and a high-yielding indica cultivar, “Takanari.” A major QTL for low-tillering, qLTN4, was detected between PCR-based markers MS10 and RM307 on the long arm of chromosome 4, with a LOD score of 15.6. The low-tillering phenotype was associated with weak growth and pale yellow phenotype; however, low-tillering plant had less reduction of grain fertility. In an F4 population (4896 plants), 563 recombinant plants were identified and the low-tillering locus was delimited to a 4.6-Mbp region between markers W1 and C5-indel3729. This region could not be further delimited because recombination is restricted in this region of qLTN4, which is near the centromere. Understanding the genetic basis of hybrid breakdown, including the low-tillering habit, will be important for improving varieties in rice breeding.

scholarly journals Genetic-basis analysis of heterotic loci in Dongxiang common wild rice (Oryza rufipogon Griff.)

2012 ◽  
Vol 94 (2) ◽  
pp. 57-61 ◽  
Author(s):  
XIAO-JIN LUO ◽  
XIAO-YUN XIN ◽  
JIN-SHUI YANG
Keyword(s):  
Wild Rice ◽  
Genetic Basis ◽  
Single Point ◽  
Crop Improvement ◽  
Dominant Gene ◽  
Introgression Line ◽  
Oryza Rufipogon ◽  
Cultivated Rice ◽  
Common Wild Rice ◽  
Point Analysis

SummaryHeterosis is widely used in genetic crop improvement; however, the genetic basis of heterosis is incompletely understood. The use of whole-genome segregating populations poses a problem for establishing the genetic basis of heterosis, in that interactions often mask the effects of individual loci. However, introgression line (IL) populations permit the partitioning of heterosis into defined genomic regions, eliminating a major part of the genome-wide epistasis. In our previous study, based on mid-parental heterosis (HMP) value with single-point analysis, 42 heterotic loci (HLs) associated with six yield-related traits were detected in wild and cultivated rice using a set of 265 ILs of Dongxiang common wild rice (Oryza rufipogon Griff.). In this study, the genetic effects of HLs were determined as the combined effects of both additive and dominant gene actions, estimated from the performance values of testcross F1s and the dominance effects estimated from the HMP values of testcross F1s. We characterized the gene action type at each HL. Thirty-eight of the 42 HLs were over-dominant, and in the absence of epistasis, four HLs were dominant. Therefore, we favour that over-dominance is a major genetic basis of ‘wild-cultivar’ crosses at the single functional Mendelian locus level.

scholarly journals Genetic Architecture of Testis and Seminal Vesicle Weights in Mice

Genetics ◽  
2001 ◽  
Vol 158 (1) ◽  
pp. 333-340 ◽  
Author(s):  
Isabelle Le Roy ◽  
Sylvie Tordjman ◽  
Danièle Migliore-Samour ◽  
Hervé Degrelle ◽  
Pierre L Roubertoux
Keyword(s):  
Seminal Vesicle ◽  
Inbred Strains ◽  
Genome Scan ◽  
Reproductive Organ ◽  
Seminal Vesicles ◽  
Total Variance ◽  
Chromosome 4 ◽  
Lod Score ◽  
Quantitative Genetic ◽  
Testicular Weight

Abstract Comparisons across 13 inbred strains of laboratory mice for reproductive organ (paired seminal vesicles and paired testes) weights indicated a very marked contrast between the C57BL/6By and NZB/BINJ mice. Subsequently these strains were selected to perform a quantitative genetic analysis and full genome scan for seminal vesicle and testis weights. An F2 population was generated. The quantitative genetic analyses indicated that each was linked to several genes. Sixty-six short sequences for length polymorphism were used as markers in the wide genome scan strategy. For weight of paired testes, heritability was 82.3% of the total variance and five QTL contributed to 72.8% of the total variance. Three reached a highly significant threshold (>4.5) and were mapped on chromosome X (LOD score 9.11), chromosome 4 (LOD score 5.96), chromosome 10 (LOD score 5.81); two QTL were suggested: chromosome 13 (LOD score 3.10) and chromosome 18 (LOD score 2.80). Heritability for weight of seminal vesicles was 50.7%. One QTL was mapped on chromosome 4 (LOD score 9.21) and contributed to 24.2% of the total variance. The distance of this QTL to the centromere encompassed the distance of the QTL linked with testicular weight on chromosome 4, suggesting common genetic mechanisms as expected from correlations in the F2. Both testis and seminal vesicle weights were associated with a reduction in the NZB/BINJ when this strain carried the YNPAR from CBA/H whereas the YNPAR from NZB/BINJ in the CBA/H strain did not modify reproductive organ weights, indicating that the YNPAR interacts with the non-YNPAR genes. The effects generated by this chromosomal region were significant but small in size.

scholarly journals Two Loci Contribute Epistastically to Heterospecific Pollen Rejection, a Postmating Isolating Barrier Between Species

2017 ◽  
Vol 7 (7) ◽  
pp. 2151-2159 ◽  
Author(s):  
Jennafer A P Hamlin ◽  
Natasha A Sherman ◽  
Leonie C Moyle
Keyword(s):  
Female Choice ◽  
Genetic Basis ◽  
Reproductive Tract ◽  
Interspecific Cross ◽  
Solanum Species ◽  
Female Reproductive Tract ◽  
Solanum Pennellii ◽  
Heterospecific Pollen ◽  
Male Gametes ◽  
Pollen Rejection

Abstract Recognition and rejection of heterospecific male gametes occurs in a broad range of taxa, although the complexity of mechanisms underlying these components of postmating cryptic female choice is poorly understood. In plants, the arena for postmating interactions is the female reproductive tract (pistil), within which heterospecific pollen tube growth can be arrested via active molecular recognition and rejection. Unilateral incompatibility (UI) is one such postmating barrier in which pollen arrest occurs in only one direction of an interspecific cross. We investigated the genetic basis of pistil-side UI between Solanum species, with the specific goal of understanding the role and magnitude of epistasis between UI QTL. Using heterospecific introgression lines (ILs) between Solanum pennellii and S. lycopersicum, we assessed the individual and pairwise effects of three chromosomal regions (ui1.1, ui3.1, and ui12.1) previously associated with interspecific UI among Solanum species. Specifically, we generated double introgression (‘pyramided’) genotypes that combined ui12.1 with each of ui1.1 and ui3.1, and assessed the strength of UI pollen rejection in the pyramided lines, compared to single introgression genotypes. We found that none of the three QTL individually showed UI rejection phenotypes, but lines combining ui3.1 and ui12.1 showed significant pistil-side pollen rejection. Furthermore, double ILs (DILs) that combined different chromosomal regions overlapping ui3.1 differed significantly in their rate of UI, consistent with at least two genetic factors on chromosome three contributing quantitatively to interspecific pollen rejection. Together, our data indicate that loci on both chromosomes 3 and 12 are jointly required for the expression of UI between S. pennellii and S. lycopersicum, suggesting that coordinated molecular interactions among a relatively few loci underlie the expression of this postmating prezygotic barrier. In addition, in conjunction with previous data, at least one of these loci appears to also contribute to conspecific self-incompatibility (SI), consistent with a partially shared genetic basis between inter- and intraspecific mechanisms of postmating prezygotic female choice.

scholarly journals The Genetic Basis of High Resistance to Rice Yellow Mottle Virus (RYMV) in Cultivars of Two Cultivated Rice Species

Plant Disease ◽  
1999 ◽  
Vol 83 (10) ◽  
pp. 931-935 ◽  
Author(s):  
M. N. Ndjiondjop ◽  
L. Albar ◽  
D. Fargette ◽  
C. Fauquet ◽  
A. Ghesquière
Keyword(s):  
Genetic Basis ◽  
Virus Isolate ◽  
Mottle Virus ◽  
F1 Hybrids ◽  
Enzyme Linked Immunosorbent Assay ◽  
Rice Yellow Mottle Virus ◽  
Recessive Resistance ◽  
Cultivated Rice ◽  
Recessive Resistance Gene ◽  
Yellow Mottle

Three cultivars of Oryza sativa (IR64, Azucena, and Gigante) and four cultivars of O. glaberrima (Tog5681, Tog5673, CG14, and SG329) were evaluated for their resistance to two isolates of rice yellow mottle virus (RYMV) by enzyme-linked immunosorbent assay (ELISA) and symptomatology. Cultivars Tog5681 and Gigante were highly resistant, and no symptoms were observed when either virus isolate was inoculated at 10 or 20 days postgermination and assayed by ELISA at 7, 14, 22, 35, 50, or 64 days postinoculation. Azucena showed a partial resistance, whereas the other cultivars were susceptible. Symptom appearance was associated with increase in ELISA absorbance in the systemically infected leaves. The best discrimination among the cultivars occurred when the plants were inoculated at 10 days postgermination. Crosses were made between the highly resistant (Gigante and Tog5681) and the susceptible (IR64) cultivars to determine the genetic basis of resistance to RYMV. Evaluation of F1 hybrids and interspecific progenies, as well as the segregation of resistance in F2 and F3 lines of the IR64 × Gigante cross, provided results consistent with the presence of a single recessive resistance gene common to Tog5681 and Gigante.

scholarly journals Yield QTL analysis of Oryza sativa x O. glumaepatula introgression lines

2013 ◽  
Vol 48 (3) ◽  
pp. 280-286 ◽  
Author(s):  
Priscila Nascimento Rangel ◽  
Rosana Pereira Vianello ◽  
Arthur Tavares Oliveira Melo ◽  
Paulo Hideo Nakano Rangel ◽  
João Antônio Mendonça ◽  
...  
Keyword(s):  
Oryza Sativa ◽  
Interspecific Cross ◽  
Rice Genome ◽  
Introgression Lines ◽  
Wild Accession ◽  
Cultivated Rice ◽  
Two Generations ◽  
Ssr Loci ◽  
Donor Parent ◽  
Effect On Yield

The objective of this work was to evaluate the yield performance of two generations (BC2F2 and BC2F9) of introgression lines developed from the interspecific cross between Oryza sativa and O. glumaepatula, and to identify the SSR markers associated to yield. The wild accession RS‑16 (O. glumaepatula) was used as donor parent in the backcross with the high yielding cultivar Cica‑8 (O. sativa). A set of 114 BC2F1 introgression lines was genotyped with 141 polymorphic SSR loci distributed across the whole rice genome. Molecular analysis showed that in average 22% of the O. glumaepatula genome was introgressed into BC2F1 generation. Nine BC2F9 introgression lines had a significantly higher yield than the genitor Cica‑8, thus showing a positive genome interaction among cultivated rice and the wild O. glumaepatula. Seven QTL were identified in the overall BC2F2, with one marker interval (4879‑EST20) of great effect on yield. The alleles with positive effect on yield came from the cultivated parent Cica‑8.

scholarly journals Two SNP Mutations Turned off Seed Shattering in Rice

Plants ◽  
2019 ◽  
Vol 8 (11) ◽  
pp. 475
Author(s):  
Yu Zhang ◽  
Jiawu Zhou ◽  
Ying Yang ◽  
Walid Hassan Elgamal ◽  
Peng Xu ◽  
...  
Keyword(s):  
Ssr Marker ◽  
Wild Relatives ◽  
Ancestral Haplotype ◽  
Recurrent Parent ◽  
Isogenic Line ◽  
Chromosome 4 ◽  
Cultivated Rice ◽  
Japonica Variety ◽  
Seed Shattering ◽  
Shed Light

Seed shattering is an important agronomic trait in rice domestication. In this study, using a near-isogenic line (NIL-hs1) from Oryza barthii, we found a hybrid seed shattering phenomenon between the NIL-hs1 and its recurrent parent, a japonica variety Yundao 1. The heterozygotes at hybrid shattering 1 (HS1) exhibited the shattering phenotype, whereas the homozygotes from both parents conferred the non-shattering. The causal HS1 gene for hybrid shattering was located in the region between SSR marker RM17604 and RM8220 on chromosome 4. Sequence verification indicated that HS1 was identical to SH4, and HS1 controlled the hybrid shattering due to harboring the ancestral haplotype, the G allele at G237T site and C allele at C760T site from each parent. Comparative analysis at SH4 showed that all the accessions containing ancestral haplotype, including 78 wild relatives of rice and 8 African cultivated rice, had the shattering phenotype, whereas all the accessions with either of the homozygous domestic haplotypes at one of the two sites, including 17 wild relatives of rice, 111 African cultivated rice and 65 Asian cultivated rice, showed the non-shattering phenotype. Dominant complementation of the G allele at G237T site and the C allele at C760T site in HS1 led to a hybrid shattering phenotype. These results help to shed light on the nature of seed shattering in rice during domestication and improve the moderate shattering varieties adapted to mechanized harvest.

scholarly journals Geographical variation in postzygotic isolation and its genetic basis within and between two Mimulus species

2010 ◽  
Vol 365 (1552) ◽  
pp. 2469-2478 ◽  
Author(s):  
Noland H. Martin ◽  
John H. Willis
Keyword(s):  
Pollen Fertility ◽  
Genetic Basis ◽  
Interspecific Cross ◽  
Local Scale ◽  
Interspecific Crosses ◽  
Postzygotic Isolation ◽  
Hybrid Fitness ◽  
Pure Species ◽  
Geographical Scale ◽  
Germination Success

The aim of this study is to investigate the evolution of intrinsic postzygotic isolation within and between populations of Mimulus guttatus and Mimulus nasutus . We made 17 intraspecific and interspecific crosses, across a wide geographical scale. We examined the seed germination success and pollen fertility of reciprocal F 1 and F 2 hybrids and their pure-species parents, and used biometrical genetic tests to distinguish among alternative models of inheritance. Hybrid seed inviability was sporadic in both interspecific and intraspecific crosses. For several crosses, Dobzhansky–Muller incompatibilities involving nuclear genes were implicated, while two interspecific crosses revealed evidence of cytonuclear interactions. Reduced hybrid pollen fertility was found to be greatly influenced by Dobzhansky–Muller incompatibilities in five out of six intraspecific crosses and nine out of 11 interspecific crosses. Cytonuclear incompatibilities reduced hybrid fitness in only one intraspecific and one interspecific cross. This study suggests that intrinsic postzygotic isolation is common in hybrids between these Mimulus species, yet the particular hybrid incompatibilities responsible for effecting this isolation differ among the populations tested. Hence, we conclude that they evolve and spread only at the local scale.

scholarly journals Identification of QTL TGW12 responsible for grain weight in rice based on recombinant inbred line population crossed by wild rice (Oryza minuta) introgression line K1561 and indica rice G1025

2020 ◽  
Author(s):  
Xiaoqiong Li ◽  
Yu Wei ◽  
Jun Li ◽  
Fangwen Yang ◽  
Ying Chen ◽  
...  
Keyword(s):  
Inbred Line ◽  
Recombinant Inbred ◽  
Wild Rice ◽  
Rice Yield ◽  
Introgression Line ◽  
Mads Box ◽  
Cultivated Rice ◽  
Yield Improvement ◽  
Oryza Minuta ◽  
Mads Box Gene

Abstract Background: Limited genetic resource in the cultivated rice may hinder further yield improvement. Some valuable genes that contribute to rice yield may be lost or lacked in the cultivated rice. Identification of the quantitative trait locus (QTL) for yield-related traits such as thousand-grain weight (TGW) from wild rice speices is desired for rice yield improvement. Results: In this study, sixteen TGW QTL were identified from a recombinant inbred line (RIL) population derived from the cross between the introgression line K1561 of Oryza minuta and the rice cultivar G1025. TGW12 , One of most effective QTL was mapped to the region of 241.47 kb between the marker 2768345 and marker 2853491 of the specific locus amplified fragment (SLAF). The origin of TGW12 was tested using three markers nearby or within the TGW12 region, but not clarified yet. Our data indicated thirty-two open reading fragments (ORFs) were present in the region. RT-PCR analysis and sequence alignment showed that the coding domain sequences of ORF12 , one MADS-box gene, in G1025 and K1561 were different due to alternative slicing, which caused premature transcription termination. The MADS-box gene was considered as a candidate of TGW12 . Conclusion: The effective QTL, TGW12 , was mapped to a segment of 241.47 kb using RILs population and a MADS-box gene was identified among several candidate genes in the segment. The region of TGW12 should be further narrowed and creation of transgenic lines will reveal the gene function. TGW12 could be applied for improvement of TGW in breeding program.

scholarly journals Genetic Analysis of a Large Family with Migraine, Vertigo, and Motion Sickness

2019 ◽  
Vol 46 (5) ◽  
pp. 512-517 ◽  
Author(s):  
Leema Reddy Peddareddygari ◽  
Phillip D. Kramer ◽  
Philip A. Hanna ◽  
Mark A. Levenstien ◽  
Raji P. Grewal
Keyword(s):  
Linkage Analysis ◽  
Motion Sickness ◽  
Autosomal Recessive ◽  
Large Family ◽  
American Family ◽  
Chromosome 4 ◽  
Microsatellite Repeat ◽  
Lod Score ◽  
Genome Wide ◽  
Multipoint Linkage

ABSTRACT:Background: Migraine is a common disorder most typically presenting as headache and often associated with vertigo and motion sickness. It is a genetically complex condition with multiple genes ultimately contributing to the predisposition and development of this episodic neurological disorder. We identified a large American family of 29 individuals of which 17 members suffered from at least one of these disorders, migraine, vertigo, or motion sickness. Many of these individuals suffered from several simultaneously. We hypothesized that vertigo and motion sickness may involve genes that are independent to those directly contributing to migraine susceptibility. Methods: Genome-wide linkage analysis performed using 400 microsatellite repeat markers spaced at 10 cM throughout the genome. The members of this family were phenotyped for each condition, migraine, vertigo, and motion sickness and analyzed separately. Statistical analysis was performed using two-point and multipoint linkage analysis employing a number of models including autosomal recessive or dominant patterns of inheritance with high and low genetic penetrance. Results: We identified a novel locus for migraine, 9q13-q22 (maximum two-point logarithm of odds [LOD] score-2.51). In addition, there are suggestive LOD scores that localize to different chromosomes for each phenotype; vertigo (chromosome 18, LOD score of 1.82) and motion sickness (chromosome 4, LOD score of 2.09). Conclusions: Our analysis supports our hypothesis that the migraine-associated vertigo and motion sickness may involve distinct susceptibility genes.

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