Dataset Information

Genetic mapping and candidate gene analysis for melon resistance to Phytophthora capsici.

ABSTRACT: Phytophthora blight is one of the most serious diseases affecting melon (Cucumis melo) production. Due to the lack of highly resistant germplasms, the progress on disease-resistant research is slow. To understand the genetics of melon resistance to Phytophthora capsici, an F2 population containing 498 individuals was developed by crossing susceptible line E31 to highly resistant line ZQK9. Genetic analysis indicated that the resistance in ZQK9 was controlled by a dominant gene, tentatively named MePhyto. Through bulked-segregant analysis (BSA-Seq) and chromosome walking techniques, the MePhyto gene was mapped to a 52.44 kb interval on chromosome 12. In this region, there were eight genes and their expression patterns were validated by qRT-PCR. Among them, one wall-associated receptor kinase (WAK) gene MELO3C002430 was significantly induced in ZQK9 after P. capsici inoculation, but not in E31. Based on the non-synonymous mutation site in MELO3C002430, a cleaved amplified polymorphic sequence (CAPS) marker, CAPS2430, was developed and this maker was co-segregated with MePhyto in both F2 population and a collection of 36 melon accessions. Thus MELO3C002430 was considered as the candidate gene and CAPS2430 was a promising marker for marker-assisted selection (MAS) in breeding. These results lay a foundation for revealing the resistance mechanism of melon to P. capsici.

SUBMITTER: Wang P

PROVIDER: S-EPMC7686303 | biostudies-literature | 2020 Nov

REPOSITORIES: biostudies-literature

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Genetic mapping and candidate gene analysis for melon resistance to Phytophthora capsici.

Wang Pingyong P Xu Xiaojun X Zhao Guangwei G He Yuhua Y Hou Chong C Kong Weihu W Zhang Jian J Liu Shuimiao S Xu Yongyang Y Xu Zhihong Z

Scientific reports 20201124 1

Phytophthora blight is one of the most serious diseases affecting melon (Cucumis melo) production. Due to the lack of highly resistant germplasms, the progress on disease-resistant research is slow. To understand the genetics of melon resistance to Phytophthora capsici, an F<sub>2</sub> population containing 498 individuals was developed by crossing susceptible line E31 to highly resistant line ZQK9. Genetic analysis indicated that the resistance in ZQK9 was controlled by a dominant gene, tentat ...[more]

PMID: 33235270

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Project description:Phytophthora root and stem rot caused by the oomycete pathogen Phytophthora sojae, is one of the most destructive diseases of soybean. Deploying soybean cultivars carrying race-specific resistance conferred by Rps genes is the most practicalapproach to managing this disease. Previously, two Rps genes, RpsUN1 and RpsUN2 conferring broad spectra of resistance to P. sojae isolates, were identified in a landrace PI 567139B and mapped to a 6.5-cM region on chromosome 3 and a 3.0-cM region on chromosome 16, corresponding to 840 kb and 600 kb of sequences, respectively,of the soybean reference genome. By analyzing ten and nine recombinants defined by genotypic and phenotypic screening of the 826 F2:3 families derived from two reciprocal crosses between the two parental lines of the mapping populations, RpsUN1 and RpsUN2 were further narrowed to a 151-kb region that harbors five genes including three NBS-LRR genes, and a 36-kb region that contains four genes including five NBS-LRR genes, respectively, according to the reference genome. Analysis of expressional changes of these nine genes before and after inoculation with the pathogen suggest that the counterparts of Glyma.03g034600 in the RpsUN1 region and the counterparts of Glyma.16g215200 and Glyma.16g214900 in the RpsUN2 region of PI 567139B may be associated with the resistance to P. sojae. It is also suggested that unequal recombination between different NBS-LRR genes in the mapped regions may have occurred, resulting in the formation of two recombinants with inconsistent genotypes and phenotypes detected by molecular markers within the fine-mapped regions. The haplotypes of genomic regions surrounding RpsUN1 and RpsUN2 in the entire soybean germplasm deposited in the US soybean germplasm collection were analyzed towards a better understanding of the origins of these two novel sources of resistance and screening of effective markers for marker-assisted selectionof these two resistance genes for soybean breeding.

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Dataset Information

Genetic mapping and candidate gene analysis for melon resistance to Phytophthora capsici.

Publications

Genetic mapping and candidate gene analysis for melon resistance to Phytophthora capsici.

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