Dataset Information

QTL associated with Gummy Stem Blight (GSB) resistance in watermelon.

ABSTRACT:

Background

Gummy stem blight (GSB), caused by Didymella bryoniae (syn. Stagonosporopsis cucurbitacearum), produces devastating symptoms on whole plants of watermelon (Citrullus lanatus) and other cucurbits, significantly reducing yield and quality. Identification of genetic determinants and sources of resistance to this devastating GSB disease in watermelon is essential for developing resistant varieties.

Results

In this study, we aimed at identifying quantitative trait loci (QTLs) linked to GSB resistance in melon. We identified the genome-wide single nucleotide polymorphisms (SNPs) by genotyping by sequencing (GBS) of an F₂ population developed from C. lanatus lines, 'PI 279461' (resistant) ✕ 'PI 223764' (susceptible). Inheritance analysis indicated that resistance to GSB is a multi-genic trait in this population. Three QTLs namely, ClGSB1.1, ClGSB10.1, and ClGSB11.1 associated with GSB resistance, explaining approximately 10% of the phenotypic variation, were identified. Among these, the QTL ClGSB1.1 on chromosome 1 is identified as a major QTL harboring five candidate genes associated with GSB resistance including two RLKs (ClC01G014900 and ClC01G015010), two WRKY transcription factors (ClC01G014910 and ClC01G014990), and one AvrRpt-cleavage domain protein (ClC01G015130).

Conclusion

Two high resolution melting (HRM) markers, WmGSB1.1-2 and WmGSB1.1-7 having a high positive correlation with the phenotypic variations, were developed. Five potential candidate genes were predicted to be associated with GSB resistance. These findings will help breeders to develop watermelon cultivars resistant to GSB.

SUBMITTER: Hong JE

PROVIDER: S-EPMC9441027 | biostudies-literature | 2022 Sep

REPOSITORIES: biostudies-literature

ACCESS DATA

Publications

QTL associated with Gummy Stem Blight (GSB) resistance in watermelon.

Hong Jeong-Eui JE Hossain Mohammad Rashed MR Jung Hee-Jeong HJ Nou Ill-Sup IS

BMC genomics 20220903 1

<h4>Background</h4>Gummy stem blight (GSB), caused by Didymella bryoniae (syn. Stagonosporopsis cucurbitacearum), produces devastating symptoms on whole plants of watermelon (Citrullus lanatus) and other cucurbits, significantly reducing yield and quality. Identification of genetic determinants and sources of resistance to this devastating GSB disease in watermelon is essential for developing resistant varieties.<h4>Results</h4>In this study, we aimed at identifying quantitative trait loci (QTLs ...[more]

PMID: 36057546

Similar Datasets

Project description:Key messageWe identified QTLs associated with gummy stem blight resistance in an interspecific F2:3 Citrullus population and developed marker assays for selection of the loci in watermelon. Gummy stem blight (GSB), caused by three Stagonosporopsis spp., is a devastating fungal disease of watermelon (Citrullus lanatus) and other cucurbits that can lead to severe yield losses. Currently, no commercial cultivars with genetic resistance to GSB in the field have been reported. Utilizing GSB-resistant cultivars would reduce yield losses, decrease the high cost of disease control, and diminish hazards resulting from frequent fungicide application. The objective of this study was to identify quantitative trait loci (QTLs) associated with GSB resistance in an F2:3 interspecific Citrullus mapping population (N = 178), derived from a cross between Crimson Sweet (C. lanatus) and GSB-resistant PI 482276 (C. amarus). The population was phenotyped by inoculating seedlings with Stagonosporopsis citrulli 12178A in the greenhouse in two separate experiments, each with three replications. We identified three QTLs (ClGSB3.1, ClGSB5.1 and ClGSB7.1) associated with GSB resistance, explaining between 6.4 and 21.1% of the phenotypic variation. The genes underlying ClGSB5.1 includes an NBS-LRR gene (ClCG05G019540) previously identified as a candidate gene for GSB resistance in watermelon. Locus ClGSB7.1 accounted for the highest phenotypic variation and harbors twenty-two candidate genes associated with disease resistance. Among them is ClCG07G013230, encoding an Avr9/Cf-9 rapidly elicited disease resistance protein, which contains a non-synonymous point mutation in the DUF761 domain that was significantly associated with GSB resistance. High throughput markers were developed for selection of ClGSB5.1 and ClGSB7.1. Our findings will facilitate the use of molecular markers for efficient introgression of the resistance loci and development of GSB-resistant watermelon cultivars.

Project description:BackgroundWatermelon is a nutritionally and economically significant crop in the US and globally. Gummy Stem Blight (GSB), caused by three cryptic Stagonosporopsis species, is one of the most devastating diseases affecting watermelon in the US, impacting most of the plant's above-ground parts. This study aimed to identify key Quantitative Trait Variants (QTVs) that include SNPs and In/Dels associated with GSB resistance in selfed derivatives of advanced multicross interspecific derivatives population derived from intercrosses between the most resistant lines of Citrullus amarus and highly susceptible cultivars of Citrullus lanatus.ResultsResistant and susceptible bulks were created by combining equimolar DNA concentrations from 30 extremely resistant derivatives and 30 extremely susceptible lines. These bulks underwent whole-genome sequencing, generating over 1 billion reads per bulk to achieve comprehensive genome coverage. The mapping percentage of the bulks to the parental genomes ranged from 92 to 99%. More than 6 million SNPs and 1 million indels were identified from the resistant parental genome, compared to fewer than 2 million SNPs and 0.4 million indels from the susceptible parental genome. QTNs associated with GSB resistance were identified using single-nucleotide polymorphism-index and Gprime methods. Statistically significant variants/loci linked to GSB resistance were found on chromosomes 1, 2, 3, 5, 7, 10, and 11. Notably, the genes Lipase class 3 family protein, Ribosome hibernation promotion factor (CaU02G00010), Ubiquitin-like-specific protease 1D (CaU03G04260), and Zinc finger CCCH domain-containing 15 (CaU03G10970) harbored the highest delta SNPs. Several previously published genes, including Avr9/Cf-9 Rapidly Elicited Protein (CaU07G12990) on chromosome 7, were also identified.ConclusionsIdentifying significant loci associated with GSB resistance has facilitated the development of PACE assays, which will aid in breeding GSB-resistant watermelon cultivars. These findings provide critical insights into the genetic basis of GSB resistance and represent a significant step towards improving the resilience of watermelon crops against this devastating disease.

Project description:Key messageFine-mapping separated Qfhs.ifa-5A into a major QTL mapping across the centromere and a minor effect QTL positioned at the distal half of 5AS. Both increase Fusarium resistance and anther extrusion. The Fusarium head blight (FHB) resistance QTL Qfhs.ifa-5A resides in the low-recombinogenic pericentromeric region of chromosome 5A making fine-mapping particularly arduous. Qfhs.ifa-5A primarily contributes resistance to fungal entry with the favorable allele descending from the highly Fusarium resistant cultivar Sumai-3. Fine-mapping a near-isogenic recombinant inbred line population partitioned the Qfhs.ifa-5A interval into 12 bins. Near-isogenic lines recombining at the interval were phenotyped for FHB severity, anther retention and plant height. Composite interval mapping separated the initially single QTL into two QTL. The major effect QTL Qfhs.ifa-5Ac mapped across the centromere and the smaller effect QTL Qfhs.ifa-5AS mapped to the distal half of 5AS. Although Qfhs.ifa-5Ac and Qfhs.ifa-5AS intervals were as small as 0.1 and 0.2 cM, their corresponding physical distances were large, comprising 44.1 Mbp and 49.2 Mbp, respectively. Sumai-3 alleles at either QTL improved FHB resistance and increased anther extrusion suggesting a pleiotropic effect of anthers on resistance. This hypothesis was supported by greenhouse experiments using the susceptible cultivar Remus and its resistant near-isogenic line NIL3 carrying the entire Qfhs.ifa-5A segment. By manually removing anthers prior to spray inoculation both, Remus and NIL3 became almost equally resistant in the early phase of the disease development and were significantly less diseased than variants without anther manipulation. At late time points the positive effect of the anther removal became smaller for Remus and disappeared completely for NIL3. Results affirm that absence of anthers enhanced resistance to initial infection but did not protect plants from fungal spreading within spikes.

Dataset Information

QTL associated with Gummy Stem Blight (GSB) resistance in watermelon.

Background

Results

Conclusion

Publications

QTL associated with Gummy Stem Blight (GSB) resistance in watermelon.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets