Genetic Analysis of S5-Interacting Genes Regulating Hybrid Sterility in Rice

Abstract Background Asian cultivated rice (Oryza sativa L.) comprises two subspecies, O. sativa subsp. indica and subsp. japonica, and the hybrids between them display strong heterosis. However, hybrid sterility (HS) limits practical use of the heterosis between these two subspecies. S5 is a major-effect locus controlling the HS of female gametes in rice, consisting of three closely-linked genes ORF3, ORF4 and ORF5 that act as a killer-protector system. The HS effects of S5 are inconsistent for different genetic backgrounds, indicating the existence of interacting genes within the genome. Results In the present study, the S5-interacting genes (SIG) and their effects on HS were analyzed by studying the hybrid progeny between an indica rice, Dular (DL) and a japonica rice, BalillaORF5+ (BLORF5+), with a transgenic ORF5+ allele. Four interacting quantitative trait loci (QTL): qSIG3.1, qSIG3.2, qSIG6.1, and qSIG12.1, were genetically mapped. To analyze the effect of each interacting locus, four near-isogenic lines (NILs) were developed. The effect of each specific locus was investigated while the other three loci were kept DL homozygous (DL/DL). Of the four loci, qSIG3.1 was the SIG with the greatest effects in which the DL allele was completely dominant. Furthermore, the DL allele displayed incomplete dominance at qSIG3.2, qSIG6.1, and qSIG12.1. qSIG3.1 will be the first choice for further fine-mapping. Conclusions Four S5-interacting QTL were identified by genetic mapping and the effect of each locus was analyzed using advanced backcrossed NILs. The present study will facilitate elucidation of the molecular mechanism of rice HS caused by S5. Additionally, it would provide the basis to explore the origin and differentiation of cultivated rice, having practical significance for inter-subspecific hybrid rice breeding programs.

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Investigation of Genetic Relationships within Miscanthus using SNP Markers Identified using SLAF-Seq

10.21203/rs.3.rs-152687/v1 ◽

2021 ◽

Author(s):

ZHIYONG Chen ◽

Yancen He ◽

Yasir Iqbal ◽

Yanlan Shi ◽

Hongmei Huang ◽

...

Keyword(s):

High Throughput ◽

High Throughput Sequencing ◽

Genetic Relationships ◽

Female Parent ◽

Snp Markers ◽

Nucleotide Polymorphisms ◽

Single Nucleotide ◽

Breeding Programs ◽

Sequencing Method ◽

Specific Locus

Abstract Background: Miscanthus, which is a leading dedicated-energy grass in Europe and in parts of Asia, is expected to play a key role in the development of the future bioeconomy. However, due to its complex genetic background, it is difficult to investigate phylogenetic relationships and the evolution of gene function in this genus. Here, we investigated 50 Miscanthus germplasms: 1 female parent (M. lutarioriparius), 30 candidate male parents (M. lutarioriparius, M. sinensis, and M. sacchariflorus), and 19 offspring. We used high-throughput Specific-Locus Amplified Fragment sequencing (SLAF-seq) to identify informative single nucleotide polymorphisms (SNPs) in all germplasms.Results: We identified 800,081 SLAF tags, of which 160,368 were polymorphic. Each tag was 264–364 bp long. The obtained SNPs were used to investigate genetic relationships within Miscanthus. We constructed a phylogenetic tree of the 50 germplasms using the obtained SNPs, and found that the germplasms fell into two clades: one clade of M. sinensis only and one clade that included the offspring, M. lutarioriparius, and M. sacchariflorus. Genetic cluster analysis indicated that M. lutarioriparius germplasm C3 was the most likely male parent of the offspring.Conclusions: As a high-throughput sequencing method, SLAF-seq can be used to identify informative SNPs in Miscanthus germplasms and to rapidly characterize genetic relationships within this genus. Our results will support the development of breeding programs utilizing Miscanthus cultivars with elite biomass- or fiber-production potential.

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Accelerated molecular breeding of novel cytoplasmic male sterility lines in rice using orfH79 or orf290 haplotypes

10.21203/rs.3.rs-19752/v1 ◽

2020 ◽

Author(s):

Yanping Tan ◽

Tong Chen ◽

Ze Tian ◽

Jiayang Li ◽

Xuequn Liu ◽

...

Keyword(s):

Cytoplasmic Male Sterility ◽

Male Sterility ◽

Higher Plants ◽

Amino Acid Sequences ◽

Cultivated Rice ◽

Maintainer Line ◽

Breeding Programs ◽

Aa Genome ◽

Allele Variation ◽

Grain Security

Abstract The identification and development of new cytoplasmic male sterility (CMS) lines in higher plants is important for the preservation of grain security and the prevention of homogenization of hybrid rice. Molecular markers assisted selection (MAS) based on CMS-associated genes or mitochondrial-specific chimeric sequences are important for rapid and effective breeding of new CMS lines and hybrids. In our study, the distribution and allele variation of orfH79 and orf290 genes were characterized from 273 wild and cultivated rice in the AA genome species. Based on the alignment of nucleotide and amino acid sequences, four accessions with orfH79 and three accessions with orf290 were screened. Four novel CMS lines carrying orfH79 haplotypes and three novel CMS lines carrying orf290 haplotypes were then developed using multiple backcross generations with a maintainer line under MAS. The breeding process used in our study provides an efficient and feasible approach for selecting new CMS lines. CMS lines selected in our study are important for enriching rice germplasm resources and guaranteeing rice breeding programs.

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Strategic Brand Management in SMEs for Competitive Advantage

Research Anthology on Small Business Strategies for Success and Survival ◽

10.4018/978-1-7998-9155-0.ch042 ◽

2021 ◽

pp. 846-866

Author(s):

Neeta Baporikar ◽

Rosalia Fotolela

Keyword(s):

Competitive Advantage ◽

Brand Management ◽

Practical Significance ◽

Unique Contribution ◽

Strategic Approach ◽

Exploratory Approach ◽

Depth Interview ◽

First Choice ◽

Brand Strategies ◽

Company Growth

This study aimed to explore how SME owner-managers perceive their roles in marketing and brand management as a strategic approach to enhance their competitiveness to ensure profits, growth, and sustainability. For any organization to grow and thrive it is essential to become customers first choice and for that it is critical to communicate their brand content through effective and strategic brand management. Hence, adopting a qualitative, exploratory approach, 10 owner-managers of SMEs and entrepreneurs in Windhoek, Namibia, were interviewed using semi-structured in-depth interview protocol. Findings reflect that SME brand strategies both in modern and traditional aspects enhance company growth. The study also proposes a framework that is of practical significance for future entrepreneurs, SMEs and brand consultants to enable SMEs to create and develop their brands for better and competitive positioning in the markets. The unique contribution of this study is how SME-focused brand strategies can act as a driver and provide impetus to profits, growth, and sustainability.

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A new source of root-knot nematode resistance from Arachis stenosperma incorporated into allotetraploid peanut (Arachis hypogaea)

Scientific Reports ◽

10.1038/s41598-019-54183-1 ◽

2019 ◽

Vol 9 (1) ◽

Author(s):

Carolina Ballén-Taborda ◽

Ye Chu ◽

Peggy Ozias-Akins ◽

Patricia Timper ◽

C. Corley Holbrook ◽

...

Keyword(s):

Genetic Basis ◽

Snp Array ◽

Nematode Resistance ◽

Major Effect ◽

Root Knot Nematode ◽

Breeding Programs ◽

Genes Encoding ◽

In The Wild ◽

Arachis Batizocoi ◽

Lrr Protein

AbstractRoot-knot nematode is a very destructive pathogen, to which most peanut cultivars are highly susceptible. Strong resistance is present in the wild diploid peanut relatives. Previously, QTLs controlling nematode resistance were identified on chromosomes A02, A04 and A09 of Arachis stenosperma. Here, to study the inheritance of these resistance alleles within the genetic background of tetraploid peanut, an F2 population was developed from a cross between peanut and an induced allotetraploid that incorporated A. stenosperma, [Arachis batizocoi x A. stenosperma]4×. This population was genotyped using a SNP array and phenotyped for nematode resistance. QTL analysis allowed us to verify the major-effect QTL on chromosome A02 and a secondary QTL on A09, each contributing to a percentage reduction in nematode multiplication up to 98.2%. These were validated in selected F2:3 lines. The genome location of the large-effect QTL on A02 is rich in genes encoding TIR-NBS-LRR protein domains that are involved in plant defenses. We conclude that the strong resistance to RKN, derived from the diploid A. stenosperma, is transferrable and expressed in tetraploid peanut. Currently it is being used in breeding programs for introgressing a new source of nematode resistance and to widen the genetic basis of agronomically adapted peanut lines.

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Allelic variations of the Wx locus in cultivated rice and their use in the development of hybrid rice in China

PLoS ONE ◽

10.1371/journal.pone.0232279 ◽

2020 ◽

Vol 15 (5) ◽

pp. e0232279 ◽

Cited By ~ 1

Author(s):

Ye Shao ◽

Yan Peng ◽

Bigang Mao ◽

Qiming Lv ◽

Dingyang Yuan ◽

...

Keyword(s):

Hybrid Rice ◽

Cultivated Rice ◽

Wx Locus ◽

Allelic Variations

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The role of meiotic drive in hybrid male sterility

Philosophical Transactions of the Royal Society B Biological Sciences ◽

10.1098/rstb.2009.0264 ◽

2010 ◽

Vol 365 (1544) ◽

pp. 1265-1272 ◽

Cited By ~ 71

Author(s):

Shannon R. McDermott ◽

Mohamed A. F. Noor

Keyword(s):

Male Sterility ◽

Hybrid Sterility ◽

Meiotic Drive ◽

Mechanistic Explanation ◽

Hybrid Progeny ◽

Hybrid Male ◽

Hybrid Male Sterility ◽

Species Formation ◽

Allelic Segregation

Meiotic drive causes the distortion of allelic segregation away from Mendelian expected ratios, often also reducing fecundity and favouring the evolution of drive suppressors. If different species evolve distinct drive-suppressor systems, then hybrid progeny may be sterile as a result of negative interactions of these systems' components. Although the hypothesis that meiotic drive may contribute to hybrid sterility, and thus species formation, fell out of favour early in the 1990s, recent results showing an association between drive and sterility have resurrected this previously controversial idea. Here, we review the different forms of meiotic drive and their possible roles in speciation. We discuss the recent empirical evidence for a link between drive and hybrid male sterility, also suggesting a possible mechanistic explanation for this link in the context of chromatin remodelling. Finally, we revisit the population genetics of drive that allow it to contribute to speciation.

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IDENTIFICATION OF WIDE COMPATIBILITY VARIETIES IN SOME TROPICAL JAPONICA RICE

Indonesian Journal of Agricultural Science ◽

10.21082/ijas.v6n1.2005.p28-31 ◽

2013 ◽

Vol 6 (1) ◽

pp. 28 ◽

Cited By ~ 1

Author(s):

A. Hairmansis ◽

Hajrial Aswidinnoor ◽

Trikoesoemaningtyas Trikoesoemaningtyas ◽

Suwarno Suwarno

Keyword(s):

Hybrid Rice ◽

Block Design ◽

Hybrid Sterility ◽

Japonica Rice ◽

Rice Varieties ◽

Major Barrier ◽

F1 Hybrid ◽

Tropical Japonica ◽

Wide Compatibility ◽

Randomized Complete Block Design

The F1 hybrid sterility in indica/japonica crosses is the major barrier in developing hybrid rice varieties between these two diverse germplasm. The sterility problem in japonica/indica hybrids can be overcome by using wide compatibility genes. The objective of this study was to identify wide compatibility varieties (WCVs) in some tropical japonica rice. Twenty five tropical japonica varieties as male parents were crossed with indica (IR64) and japonica (Akitakomachi) testers as female parents. The crosses were planted following a randomized complete block design with three replications. Varieties having average spikelet fertility of more than 70% with both the indica and japonica testers were rated as WCVs. Result from this study showed that six tropical japonica varieties were classified as WCVs, i.e., Cabacu, Grogol, Kencana Bali, Klemas, Lampung Lawer, and Napa. Hybrid sterility is caused by partial sterility of male and female gametes. The WCVs from the present study can be used in hybrid rice breeding program to solve hybrid sterility in indica/japonica hybrids.

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