Dataset Information

Construction of a high-density genetic map and localization of grazing-tolerant QTLs in Medicago falcata L.

ABSTRACT:

Background

Using genomic DNA from 79 F1 plants resulted from a crossing between parents with strong and weak grazing tolerance in Medicago falcata L., we generated an EcoRI restriction site-associated DNA (RAD) sequencing library. After sequencing and assembly, a high-density genetic map with high-quality SNP markers was constructed, with a total length of 1312.238 cM and an average density of 0.844 SNP/cM.

Methods

The phenotypic traits of 79 F1 families were observed and the QTLS of 6 traits were analyzed by interval mapping.

Results

Sixty three QTLs were identified for seven traits with LOD values from 3 to 6 and the contribution rates from 15% to 30%. Among the 63 QTLs, 17 were for natural shoot height, 12 for rhizome Length, 10 for Shoot canopy diameter, 9 for Basal plant diameter, 6 for stem number, 5 for absolute shoot height, and 4 for rhizome width. These QTLs were concentrated on LG2, LG4, LG5, LG7, and LG8. LG6 had only 6 QTLs. According to the results of QTL mapping, comparison of reference genomes, and functional annotation, 10 candidate genes that may be related to grazing tolerance were screened. qRT-PCR analysis showed that two candidate genes (LOC11412291 and LOC11440209) may be the key genes related to grazing tolerance of M. falcata.

Conclusion

The identified trait-associated QTLs and candidate genes in this study will provide a solid foundation for future molecular breeding for enhanced grazing-tolerance in M. falcata.

SUBMITTER: Zhou X

PROVIDER: S-EPMC9574245 | biostudies-literature | 2022

REPOSITORIES: biostudies-literature

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Publications

Construction of a high-density genetic map and localization of grazing-tolerant QTLs in <i>Medicago falcata</i> L.

Zhou Xinyue X Li Xiaojie X Zhang Xiaoming X Yin Dabao D Wang Junjie J Zhao Yan Y

Frontiers in plant science 20221003

<h4>Background</h4>Using genomic DNA from 79 F1 plants resulted from a crossing between parents with strong and weak grazing tolerance in <i>Medicago falcata</i> L., we generated an <i>EcoRI</i> restriction site-associated DNA (RAD) sequencing library. After sequencing and assembly, a high-density genetic map with high-quality SNP markers was constructed, with a total length of 1312.238 cM and an average density of 0.844 SNP/cM.<h4>Methods</h4>The phenotypic traits of 79 F1 families were observe ...[more]

PMID: 36262664

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