Near-isogenic Lines Research Articles

Comparison of gene expression changes in two wheat varieties with different phenotype to strip rust using RNA-Seq analysis

The fungus Puccinia striiformis f. sp. tritici (Pst) is an important threat to wheat production because it can cause wheat stripe rust. The present study aimed to identify new stripe rust resistance genes and to provide a theoretical and practical basis for breeding wheat varieties with broad spectrum, stable, and durable resistance. Wheat leaves inoculated with wheat stripe rust fungus Chinese yellow rust 34 were collected at different time points for transcriptomic analysis based on the wheat stripe rust susceptible varieties AVOCET S (AVS) and AVSYr15NIL [near-isogenic line (NIL) derived from AVS]. The results showed that the number of upregulated genes in the two varieties was 294, 364, 398, and 604, and the number of downregulated genes was 520, 178, 570, and 345 on the 1st, 3rd, 5th, and 7th days post inoculation, respectively. Gene Ontology and Kyoto Encyclopedia of Gene and Genomes enrichment analyses found enrichment of differentially expressed genes in the peroxisome proliferators-activated receptor signaling pathways, plant–pathogen interaction, and styrene acrylic acid biosynthesis that encoded protein kinases, signal transduction, transcription factors, and functional protein components. Differentially expressed genes were randomly selected for quantitative reverse transcription PCR analysis, and the change trend was the same as in the transcriptome data. The results of this study suggest that genes in AVSYr15NIL related to the stripe rust response could be valuable for understanding the mechanisms involved in stripe rust resistance.

Comparison of cotton (Gossypium hirsutum) hybrids and their non-transgenic in India

It is still not clear whether differential response of Bt cotton and conventional non-Bt cotton genotypes in terms of growth, phenology and yield ability are hypothetical or realistic. This study investigated the response of three Bt cotton hybrids in comparison to their conventional non-transgenic version (near-isogenic lines) along with two locally adapted genotypes for growth, yield attributes, phenological characteristics and rooting behavior. Therefore, two experiments were conducted during summer season of year 2016 and 2017 to evaluate differences among 3 popular Bt cotton hybrids along with their non-Bt version. First field experiment was conducted as a pot study wherein shoot and root parameters of 3 Bt cotton hybrids (Ankur 3028, MRC 7017, Bioseed 6588) were compared with their non-Bt version along with 2 local checks (i.e.,hirsutum cotton Cv. F2228 and arboreum cottonCv. FDK124). Second field experiment evaluated growth, phenological characteristics, yield attributes and productivity potential of above mentioned Bt and non-Bt hybrids. Findings of pot experiment could not establish any significant difference among studied Bt and non-Bt hybrids for root and shoot characteristics. However, arboreum cotton FDK124 exhibited higher root length than all genotypes. Results of second experiment revealed significant differences for phenological characteristics, wherein Bt version of all the tested hybrids exhibited earliness for flowering initiation, 50 % flowering and days to maturity over their non-Bt version. Seed cotton yield (SCY) in all hybrids possessing Bt gene was significantly higher than their non-Bt version primarily due to higher bolls plant-1. Studies conclude that introgression of Bt gene could not alter rooting parameters of evaluated cotton genotypes but significantly affected phenological stages by inducing earliness and higher SCY in Bt versions due to improved bolls plant-1. Keywords: Bt cotton; Near-isogenic lines; Phenology; Root dry matter; Seed cotton yield

Tissues and mechanisms associated with Verticillium wilt resistance in tomato using bi-grafted near-isogenic lines.

Host resistance is the primary means to control Verticillium dahliae, a soil-borne pathogen causing major losses on a broad range of plants, including tomato. The tissues and mechanisms responsible for resistance remain obscure. In the field, resistant tomato used as rootstocks does not confer resistance. Here, we created bi-grafted plants with near-isogenic lines (NILs) exhibiting (Ve1) or lacking (ve1) resistance to V. dahliae race 1. Ten days after inoculation, scion and rootstock tissues were subjected to differential gene expression and co-expression network analyses. Symptoms only developed in susceptible scions regardless of the rootstock. Infection caused more dramatic alteration of tomato gene expression in susceptible compared to resistant tissues, including pathogen receptor, signaling pathway, PR protein, and cell wall modification genes. Differences were observed between scions and rootstocks, primarily related to physiological processes in these tissues. Gene expression in scions was influenced by the rootstock genotype. A few genes were associated with the Ve1 genotype, which was independent of infection or tissue type. Several were physically clustered, some near the Ve1 locus on chromosome 9. Transcripts mapped to V. dahliae were dominated by secreted candidate effector proteins. These findings advance knowledge of molecular mechanisms underlying the tomato-V. dahliae interaction.

Genetic loci regulating the concentrations of anthocyanins and proanthocyanidins in the pericarps of purple and red rice.

The pigmented flavonoids, anthocyanins and proanthocyanidins, have health promoting properties. Previous work determined that the genes Pb and Rc turn on and off the biosynthesis of anthocyanins (purple) and proanthocyanidins (red), respectively. Not yet known is how the concentrations of these pigmented flavonoids are regulated in grain pericarps. Quantitative trait locus (QTL) analysis in a population of rice (Oryza sativa L.) F5 recombinant inbred lines from white pericarp "IR36ae" x red+purple pericarp "242" revealed three QTLs associated with grain concentrations of anthocyanins (TAC) or proanthocyanidins (PA). Both TAC and PA independently mapped to a 1.5 Mb QTL region on chromosome 3 between RM3400 (at 15.8 Mb) and RM15123 (17.3 Mb), named qPR3. Across 2 years, qPR3 explained 36.3% of variance in TAC and 35.8% in PA variance not attributable to Pb or Rc. The qPR3 region encompasses Kala3, a MYB transcription factor previously known to regulate purple grain characteristics. Study of PbPbRcrc progeny showed that TAC of RcRc near isogenic lines (NILs) was 2.1-4.5x that of rcrc. Similarly, study of PbPbRcRc NILs, which had 70% higher PA than pbpbRcRc NILs, revealed a mutual enhancement, not a trade-off between these compounds that share precursors. This suggests that Pb and Rc upregulate genes in a shared pathway as they activate TAC and PA synthesis, respectively. This study provides molecular markers for facilitating marker-assisted selection of qPR3, qPR5, and qPR7 to enhance grain concentrations of pigmented flavonoids and documented that stacking Rc and Pb genes further increases both flavonoid compounds.

A systematic dissection in oilseed rape provides insights into the genetic architecture and molecular mechanism of yield heterosis.

Heterosis refers to the better performance of cross progeny compared with inbred parents, and its utilization contributes greatly to agricultural production. Several hypotheses have been proposed to explain heterosis mainly including dominance, over-dominance (or pseudo-overdominance) and epistasis. However, systematic dissection and verification of these hypotheses are rarely documented. Here, comparison of heterosis level across different traits showed that the strong heterosis of composite traits (such as yield) could be attributed to the multiplicative effects of moderate heterosis of component traits, whether at the genome or locus level. Yield heterosis was regulated by a complex trait-QTL network that was characterized by obvious centre-periphery structure, hub QTL, complex up/downstream and positive/negative feedback relationships. More importantly, we showed that better-parent heterosis on yield could be produced in a cross of two near-isogenic lines by the pyramiding and complementation of two major heterotic QTL showing partial-dominance on yield components. The causal gene (BnaA9.CYP78A9) of QC14 was identified, and its heterotic effect results from the heterozygous status of a CACTA-like transposable element in its upstream regulatory region, which led to partial dominance at expression and auxin levels, thus resulting in non-additive expression of downstream responsive genes involved in cell cycle and proliferation, eventually leading to the heterosis of cell number. Taken together, the results at the phenotypic, genetic and molecular levels were highly consistent, which demonstrated that the pyramiding effect of heterotic QTL and the multiplicative effect of individual component traits could well explain substantial parts of yield heterosis in oilseed rape. These results provide in-depth insights into the genetic architecture and molecular mechanism of yield heterosis.

Multiplexed Host-Induced Gene Silencing of Aspergillus flavus Genes Confers Aflatoxin Resistance in Groundnut.

Aflatoxins are immunosuppressive and carcinogenic secondary metabolites, produced by the filamentous ascomycete Aspergillus flavus, that are hazardous to animal and human health. In this study, we show that multiplexed host-induced gene silencing (HIGS) of Aspergillus flavus genes essential for fungal sporulation and aflatoxin production (nsdC, veA, aflR, and aflM) confers enhanced resistance to Aspergillus infection and aflatoxin contamination in groundnut (<20 ppb). Comparative proteomic analysis of contrasting groundnut genotypes (WT and near-isogenic HIGS lines) supported a better understanding of the molecular processes underlying the induced resistance and identified several groundnut metabolites that might play a significant role in resistance to Aspergillus infection and aflatoxin contamination. Fungal differentiation and pathogenicity proteins, including calmodulin, transcriptional activator-HacA, kynurenine 3-monooxygenase 2, VeA, VelC, and several aflatoxin pathway biosynthetic enzymes, were downregulated in Aspergillus infecting the HIGS lines. Additionally, in the resistant HIGS lines, a number of host resistance proteins associated with fatty acid metabolism were strongly induced, including phosphatidylinositol phosphate kinase, lysophosphatidic acyltransferase-5, palmitoyl-monogalactosyldiacylglycerol Δ-7 desaturase, ceramide kinase-related protein, sphingolipid Δ-8 desaturase, and phospholipase-D. Combined, this knowledge can be used for groundnut pre-breeding and breeding programs to provide a safe and secure food supply.

Transcriptomic profiling of near-isogenic lines reveals candidate genes for a significant locus conferring metribuzin resistance in wheat

BackgroundWeeds reduce wheat yields in dryland farming systems. Herbicides such as metribuzin are commonly used to control weeds. However, wheat has a narrow safety margin against metribuzin. Standing crops such as wheat with weeds in the same field can also be killed by the same dose of metribuzin. Therefore, it is important to identify metribuzin resistance genes and understand the resistance mechanism in wheat for sustainable crop production. A previous study identified a significant metribuzin resistance wheat QTL, Qsns.uwa.4 A.2, explaining 69% of the phenotypic variance for metribuzin resistance.ResultsTwo NIL pairs with the most contrasting performance in the metribuzin treatment and different in genetic backgrounds were compared using RNA sequence analysis, identifying nine candidate genes underlying Qsns.uwa.4 A.2 responsible for metribuzin resistance. Quantitative RT-qPCR further validated the candidate genes, with TraesCS4A03G1099000 (nitrate excretion transporter), TraesCS4A03G1181300 (aspartyl protease), and TraesCS4A03G0741300 (glycine-rich proteins) identified as key factors for metribuzin resistance.ConclusionIdentified markers and key candidate genes can be used for selecting metribuzin resistance in wheat.

Don't panic any more: MORE PANICLES 3 increases rice yield at elevated CO2 levels.

Don't panic any more: MORE PANICLES 3 increases rice yield at elevated CO2 levels.

Long coleoptile genotype and soil texture interactions determine establishment success and early growth parameters of wheat sown at depth

Long coleoptile (LC) - wheat genotypes sown deeper (> 10 cm) than current practice (< 5 cm) enables earlier deep sowing into subsurface soil moisture. The LC genotype shows promise to broaden sowing windows and remove reliance on the shifting seasonal break for crop establishment. The suitability of this sowing strategy to the highly variable soils of the southern Australian wheatbelt warrants investigation to identify suitable environments for potential establishment benefits. We conducted controlled environment room (CER) and field experiments using pairs of near-isogenic-lines (NILs) that differed genetically only for coleoptile length. The experiments investigated the suitability of deep sown (12 cm) LC wheats in soils with different texture (sand versus loam). The CER experiment identified that LC genotypes exhibited greater emergence and early seedling growth, producing greater shoot and root biomass, when deep sown (12 cm) in loam. While LC and short coleoptile (SC) genotypes produced similar shoot growth when sown at depth in sand, LC produced greater root biomass reflected in more seminal roots. In the field on sand, LC and SC had similar emergence and early shoot growth characteristics at all sowing depths (5, 8 and 10 cm). However, the heavy-textured, loam soil reduced seedling emergence and restricted leaf growth with deep sowing (12 cm) in the SC. Our results indicate that the LC trait was more critical for plant emergence and early growth parameters (shoot and root biomass) from depth in a heavier textured loam compared with a sand. By identifying environments that will likely benefit most from deep sown LC, we are one step closer to adapting crop production to shifting rainfall patterns in southern Australia.

Introgression and Environmental Effects on Gene Expression and Aroma Volatiles As Biomarkers in a Melon Near-Isogenic Line

Introgression and Environmental Effects on Gene Expression and Aroma Volatiles As Biomarkers in a Melon Near-Isogenic Line

Mapping and validation of quantitative trait loci associated with dorsal aleurone thickness in rice (Oryza sativa)

Mapping of QTLs for dorsal aleurone thickness (DAT) was performed using chromosome segment substitution lines in rice. Three QTLs, qDAT3.1, qDAT3.2, and qDAT7.1, were detected in multiple environments. As a specified endosperm cell type, the aleurone has an abundance of various nutrients. Increasing the number of aleurone layers is a practicable way of developing highly nutritious cereals. Identifying genes that can increase aleurone thickness is useful for the breeding of aleurone traits to improve the nutritional and health values of rice. Here, we found that iodine staining could efficiently distinguish the aleurone layers, which revealed great variation of the aleurone thickness in rice, especially at the dorsal side of the seed. Therefore, we used a population of chromosome segmental substitution lines (CSSLs) derived from Koshihikari and Nona Bokra for quantitative trait locus (QTL) analysis of the dorsal aleurone thickness (DAT). Three QTLs, qDAT3.1, qDAT3.2, and qDAT7.1, were detected in multiple seasons. Among these, qDAT3.2 colocalizes with Hd6 and Hd16, two QTLs previously identified to regulate the heading date of Koshihikari, explaining the negative correlation between the DAT and days to heading (DTH) in rice. We also provide evidence that early-heading ensures the filling of rice seed under a relatively high temperature to promote aleurone thickening. qDAT7.1, the most stable QTL expressed in different environments, functions independently from heading date. Although Nona Bokra has a lower DAT, its qDAT7.1 allele significantly increased DAT in rice, which was further validated using two near-isogenic lines (NILs). These findings pave the way for further gene cloning of aleurone-related QTLs and may aid the development of highly nutritious rice.

Divergent selection of KNR6 maximizes grain production by balancing the flowering-time adaptation and ear size in maize.

Divergent selection of KNR6 maximizes grain production by balancing the flowering-time adaptation and ear size in maize.

Gene B5 in Cotton Confers High and Broad Resistance to Bacterial Blight and Conditions High Amounts of Sesquiterpenoid Phytoalexins.

Bacterial blight resistance gene B5 has received little attention since it was first described in 1950. A near-isogenic line (NIL) of Gossypium hirsutum cotton, AcB5, was generated in an otherwise bacterial-blight-susceptible 'Acala 44' background. The introgressed locus B5 in AcB5 conferred strong and broad-spectrum resistance to bacterial blight. Segregation patterns of test crosses under Oklahoma field conditions indicated that AcB5 is likely homozygous for resistance at two loci with partial dominance gene action. In controlled-environment conditions, two of the four copies of B5 were required for effective resistance. Contrary to expectations of gene-for-gene theory, AcB5 conferred high resistance toward isogenic strains of Xanthomonas citri subsp. malvacearum carrying cloned avirulence genes avrB4, avrb7, avrBIn, avrB101, and avrB102, respectively, and weaker resistance toward the strain carrying cloned avrb6. The hypothesis that each B gene, in the absence of a polygenic complex, triggers sesquiterpenoid phytoalexin production was tested by measurement of cadalene and lacinilene phytoalexins during resistant responses in five NILs carrying different B genes, four other lines carrying multiple resistance genes, as well as susceptible Ac44E. Phytoalexin production was an obvious, but variable, response in all nine resistant lines. AcB5 accumulated an order of magnitude more of all four phytoalexins than any of the other resistant NILs. Its total levels were comparable to those detected in OK1.2, a highly resistant line that possesses several B genes in a polygenic background.

Transcriptome analysis of two near-isogenic lines of bell pepper (Capsicum annuum) infected with bell pepper endornavirus and pepper mild mottle virus.

Transcriptome analysis of two near-isogenic lines of bell pepper (Capsicum annuum) infected with bell pepper endornavirus and pepper mild mottle virus.

Fine mapping and validation of a stable QTL for thousand-kernel weight in wheat (Triticum aestivum L.)

Thousand-kernel weight (TKW) is a measure of grain weight, a target of wheat breeding. The object of this study was to fine-map a stable quantitative trait loci (QTL) for TKW and identify its candidate gene in a recombinant inbred line (RIL) population derived from the cross of Kenong 9204 (KN9204) and Jing 411 (J411). On a high-density genetic linkage map, 24, 26 and 25 QTL were associated with TKW, kernel length (KL), and kernel width (KW), respectively. A major and stable QTL, QTkw-2D, was mapped to an 8.3 cM interval on chromosome arm 2DL. By saturation of polymorphic markers in its target region, QTkw-2D was confined to a 9.13 Mb physical interval using a secondary mapping population derived from a residually heterozygous line (F6:7). This interval was further narrowed to 2.52 Mb using QTkw-2D near-isogenic lines (NILs). NILsKN9204 had higher fresh and dry weights than NILsJ411 at various grain-filling stages. The TKW and KW of NILsKN9204 were much higher than those of NILsJ411 in field trials. By comparison of both DNA sequence and expression between KN9204 and J411, TraesCS2D02G460300.1 (TraesKN2D01HG49350) was assigned as a candidate gene for QTkw-2D. This was confirmed by RNA sequencing (RNA-seq) of QTkw-2D NILs. These results provide the basis of map-based cloning of QTkw-2D, and DNA markers linked to the candidate gene may be used in marker-assisted selection.

Untargeted Metabolomics Reveals a Multi-Faceted Resistance Response to Fusarium Head Blight Mediated by the Thinopyrum elongatum Fhb7E Locus Transferred via Chromosome Engineering into Wheat.

The Thinopyrum elongatum Fhb7E locus has been proven to confer outstanding resistance to Fusarium Head Blight (FHB) when transferred into wheat, minimizing yield loss and mycotoxin accumulation in grains. Despite their biological relevance and breeding implications, the molecular mechanisms underlying the resistant phenotype associated with Fhb7E have not been fully uncovered. To gain a broader understanding of processes involved in this complex plant-pathogen interaction, we analysed via untargeted metabolomics durum wheat (DW) rachises and grains upon spike inoculation with Fusarium graminearum (Fg) and water. The employment of DW near-isogenic recombinant lines carrying or lacking the Th. elongatum chromosome 7E region including Fhb7E on their 7AL arm, allowed clear-cut distinction between differentially accumulated disease-related metabolites. Besides confirming the rachis as key site of the main metabolic shift in plant response to FHB, and the upregulation of defence pathways (aromatic amino acid, phenylpropanoid, terpenoid) leading to antioxidants and lignin accumulation, novel insights were revealed. Fhb7E conferred constitutive and early-induced defence response, in which specific importance of polyamine biosynthesis, glutathione and vitamin B6 metabolisms, along with presence of multiple routes for deoxynivalenol detoxification, was highlighted. The results suggested Fhb7E to correspond to a compound locus, triggering a multi-faceted plant response to Fg, effectively limiting Fg growth and mycotoxin production.

Genome-wide identification and characterization of circRNAs in wheat tiller

This study found that the intergenic circRNAs of wheat were more abundant than those of other plants. More importantly, a circRNA-mediated network associated with tillering was constructed for the first time. Circular RNAs (circRNAs) are a class of endogenous non-coding RNAs with covalently closed circular structures, which play an important role in transcriptional and post-transcriptional regulation. Tiller is an important agronomic trait that determines plant morphological architecture and affects spike number in wheat. However, no studies on the characteristics and functions of circRNAs involved in the regulation of wheat tiller. Here, we performed a genome-wide identification of circRNAs using ribosomal-depleted RNA-seq from wheat tiller of two pairs near-isogenic lines. A total of 686 circRNAs were identified and distributed on 21 chromosomes of wheat, of which 537 were novel circRNAs. Unlike other plants, the majority of these circRNAs (61.8%) were derived from intergenic regions. One circRNA-mediated network associated with tillering was constructed through weighted gene co-expression network analysis, including 323 circRNAs, 117 miRNAs, and 968 mRNAs. GO and pathway enrichment analysis of mRNAs suggested that these circRNAs are involved in cell cycle, ncRNA export from nucleus, developmental process, plant hormone signal transduction, MAPK signaling pathway, RNA degradation. Of these circRNAs, ten circRNAs are associated with known tillering/branching genes in rice or Arabidopsis thaliana, including OsCesA7, EBR1, DTE1, CRD1, LPA1, PAY1, LRK1, OsNR2, OsCCA1, OsBZR1. In summary, we present the first study of the identification and characterization of circRNAs in wheat tiller, and the results suggest these circRNAs associated with tillering could play an important role in wheat tiller formation and development.

Targeting Disease Susceptibility Genes in Wheat Through wide Hybridization with Maize Expressing Cas9 and Guide RNA.

Two genes (TaHRC and Tsn1) conferring susceptibility to Fusarium head blight and tan spot, Septoria nodorum blotch, and spot blotch in wheat were targeted through wide hybridization with maize expressing Cas9 and guide RNA (gRNA). For each gene, two target sites were selected and corresponding gRNA expression cassettes were synthesized and cloned into a binary vector carrying the CRISPR/Cas9-mediated genome editing machinery. The constructed binary vectors were used to transform the hybrid maize Hi-II through an Agrobacterium-mediated approach to generate T0 and T1 plants, which were used to cross with wheat variety Dayn for targeting Tsn1 or the susceptible allele (TaHRC-S) of TaHRC as well as with the near-isogenic line (Day-Fhb1) of Dayn for targeting the resistant allele (TaHRC-R) of TaHRC. Haploid embryos were rescued in vitro from the wide crosses to generate haploid plants. PCR amplification and sequencing indicated that 15 to 33% of the haploid plants contained the target gene with mutations at the target sites. This wheat × maize hybridization combined with genome editing approach provides a useful alternative tool, not only for targeting susceptibility genes to improve disease resistance without regulatory issues, but also for understanding gene function in wheat. [Formula: see text] Copyright © 2023 The Author(s). This is an open access article distributed under the CC BY-NC-ND 4.0 International license.

A genome-wide analysis of the USDA Soybean Isoline Collection.

The USDA Soybean Isoline Collection has been an invaluable resource for the soybean genetics and breeding community. This collection, established in 1972, consists of 611 near-isogenic lines (NILs) carrying one or multiple genes conferring traits that had been determined to exhibit Mendelian inheritance. It has been used in multiple studies on the genetic basis, physiology, and agronomy of these qualitative traits. Here, we used publicly available genotype (SoySNP50K), phenotype, and pedigree data on this collection to characterize the isogenicity of the NILs and identify chromosomal positions of unmapped genes. A total of 368 NILs had at least 80% identity to their recurrent parent and, thus, were useful for what can be called introgression mapping. Both on-target and off-target introgressions were evaluated. The size of on-target introgressions into individual NILs ranged from 61kb to 8.4 Mb, whereas off-target introgressions ranged from 2.6kb to 54.8 Mb. The observed large off-target introgressions indicated that some NILs carry introgressions nearly the size of an entire chromosome. By applying introgression mapping to genes that had never been mapped, we identified the likely chromosomal positions of six such genes: ab, im, lo, Np, pc, and Rpm. The size of mapping intervals was large in some cases (10.28 Mb for im) but small in others (0.21 Mb for Np). The results reported herein will provide future researchers with a resource to help select informative NILs for future studies, and provide a starting point to further fine map, and ultimately clone and functionally characterize these six soybean genes.

Characterization and fine-mapping of a new Asian rice selfish genetic locus S58 in Asian-African rice hybrids.

We identified and fine-mapped S58, a selfish genetic locus from Asian rice that confers hybrid male sterility in crosses between Asian and African cultivated rice, and found a natural neutral allele in Asian rice lines that will be useful for overcoming S58-mediated hybrid sterility. Hybrids between Asian cultivated rice (Oryza sativa L.) and African cultivated rice (Oryza glaberrima Steud) display severe hybrid sterility (HS), hindering the utilization of strong heterosis in hybrids between these species. Several African rice selfish loci causing HS in Asian-African cultivated rice hybrids have been identified, but few such Asian rice selfish loci have been found. In this study, we identified an Asian rice selfish locus, S58, which causes hybrid male sterility (HMS) in hybrids between the Asian rice variety 02428 and the African rice line CG14. Genetic analysis confirmed that S58 causes a transmission advantage for the Asian rice S58 allele in the hybrid offspring. Genetic mapping with near-isogenic lines and DNA markers delimited S58 to 186 kb and 131 kb regions of chromosome 1 in 02428 and CG14, respectively, and revealed complex genomic structural variation over these mapped regions. Gene annotation analysis and expression profiling analyses identified eight anther-expressed candidate genes potentially responsible for S58-mediated HMS. Comparative genomic analysis determined that some Asian cultivated rice varieties harbor a 140 kb fragment deletion in this region. Hybrid compatibility analysis showed that this large deletion allele in some Asian cultivated rice varieties can serve as a natural neutral allele, S58-n, that can overcome S58-mediated interspecific HMS. Our study demonstrates that this selfish genetic element from Asian rice is important for HMS between Asian and African cultivated rice, broadening our understanding of interspecific HS. This study also provides an effective strategy for overcoming HS in future interspecific rice breeding.