Dataset Information

Mapping of QTLs conferring high grain length-breadth relative expansion during cooking in rice cultivar Paw San Hmwe.

ABSTRACT: Paw San Hmwe (PSH) is a high-quality rice cultivar from Myanmar. PSH has short and broad grains, but the grains become slender after cooking. This desirable feature can be described as a high value of grain length-breadth relative expansion index (GREI). To understand the genetic basis of high GREI in PSH, we crossed PSH with Guang 8B (G8B), a rice cultivar from China with low GREI, to develop an F₂ population and a subsequent F_2:3 population. Based on the phenotypes of these two populations measured in two years and using the method of sequencing-based bulked segregant analysis followed by verification with conventional linkage-based QTL mapping method, we mapped three QTLs for GREI. The three QTLs were located on chromosomes 3, 5 and 12, respectively, with the trait-increasing alleles all from PSH, and could explain a total of 62.5% of the phenotypic variance and 84.1% of the additive genetic variance. The results suggest that the three QTLs would be useful for the genetic improvement of GREI in rice, and the linked markers will facilitate the selection of the favorable alleles from PSH in breeding.

SUBMITTER: Thi KM

PROVIDER: S-EPMC7878942 | biostudies-literature | 2020 Dec

REPOSITORIES: biostudies-literature

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Mapping of QTLs conferring high grain length-breadth relative expansion during cooking in rice cultivar Paw San Hmwe.

Thi Khin Mar KM Zheng Yan Y Khine Ei Ei EE Nyein Ei Ei EE Lin Min Htay Wai MHW Oo Khin Than KT New Win Win WW Thet Moe Zin Zi MZZ Khaing Moe Moe MM Moe Myat Myat MM Aye San San SS Wu Weiren W

Breeding science 20201028 5

Paw San Hmwe (PSH) is a high-quality rice cultivar from Myanmar. PSH has short and broad grains, but the grains become slender after cooking. This desirable feature can be described as a high value of grain length-breadth relative expansion index (GREI). To understand the genetic basis of high GREI in PSH, we crossed PSH with Guang 8B (G8B), a rice cultivar from China with low GREI, to develop an F<sub>2</sub> population and a subsequent F<sub>2:3</sub> population. Based on the phenotypes of the ...[more]

PMID: 33603551

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Dataset Information

Mapping of QTLs conferring high grain length-breadth relative expansion during cooking in rice cultivar Paw San Hmwe.

Publications

Mapping of QTLs conferring high grain length-breadth relative expansion during cooking in rice cultivar Paw San Hmwe.

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