Mapping QTLs underpin nutrition components in aromatic rice germplasm

PLoS One. 2020 Jun 11;15(6):e0234395. doi: 10.1371/journal.pone.0234395. eCollection 2020.

Abstract

As rice is an important staple food globally, research for development and enhancement of its nutritional value it is an imperative task. Identification of nutrient enriched rice germplasm and exploiting them for breeding programme is the easiest way to develop better quality rice. In this study, we analyzed 113 aromatic rice germplasm in order to identify quantitative trait loci (QTL) underpinning nutrition components and determined by measuring the normal frequency distribution for Fe, Zn, amylose, and protein content in those rice germplasm. Comparatively, the germplasm Radhuni pagal, Kalobakri, Thakurbhog (26.6 ppm) and Hatisail exhibited the highest mean values for Fe (16.9 ppm), Zn (34.1 ppm), amylose (26.6 ppm) and protein content (11.0 ppm), respectively. Moreover, a significant linear relationship (R2 = 0.693) was observed between Fe and Zn contents. Cluster analysis based on Mahalanobis D2 distances revealed four major clusters of 113 rice germplasm, with cluster III containing a maximum 37 germplasm and a maximum inter-cluster distance between clusters III and IV. The 45 polymorphic SSRs and four trait associations exhibited eight significant quantitative trait loci (QTL) located on eight different chromosomes using composite interval mapping (CIM). The highly significant QTL (variance 7.89%, LOD 2.02) for protein content (QTL.pro.1) was observed on chromosome 1 at 94.9cM position. Also, four QTLs for amylose content were observed with the highly significant QTL.amy.8 located on chromosome 8 exhibiting 7.2% variance with LOD 1.83. Only one QTL (QTL.Fe.9) for Fe content was located on chromosome 9 (LOD 1.24), and two (QTL.Zn.4 and QTL.Zn.5) for Zn on chromosome 4 (LOD 1.71) and 5 (LOD 1.18), respectively. Overall, germplasm from clusters III and IV might offer higher heterotic response with the identified QTLs playing a significant role in any rice biofortification breeding program and released with development of new varieties.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amylose / analysis
  • Biofortification / methods
  • Crops, Agricultural / chemistry
  • Crops, Agricultural / classification
  • Crops, Agricultural / genetics
  • Food, Fortified / analysis
  • Genes, Plant
  • Genetic Markers
  • Iron / analysis
  • Nutritive Value
  • Oryza / chemistry
  • Oryza / classification
  • Oryza / genetics*
  • Phenotype
  • Plant Breeding / methods
  • Plant Proteins, Dietary / analysis
  • Quantitative Trait Loci*
  • Regression Analysis
  • Seeds / chemistry
  • Seeds / genetics
  • Zinc / analysis

Substances

  • Genetic Markers
  • Plant Proteins, Dietary
  • Amylose
  • Iron
  • Zinc

Grants and funding

National Agricultural Technology Project (NATP): Phase-1 in Bangladesh. Financed by Bangladesh Agricultural Research Council (BARC), Farmgate, Dhaka. Grant No. 12. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.”. Lead author MZ Islam received fellowship from this grant. M. Khalequzzaman received project award”. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.