Sothea OUK - Academia.edu (original) (raw)

Papers by Sothea OUK

Research paper thumbnail of Quality evaluation, fatty acid analysis and untargeted profiling of volatiles in Cambodian rice

Research paper thumbnail of Breeding Hybrid Rice with Genes Resistant to Diseases and Insects Using Marker-Assisted Selection and Evaluation of Biological Assay

Plant Breeding and Biotechnology, 2019

Developing elite hybrid rice varieties is one important objective of rice breeding programs. Seve... more Developing elite hybrid rice varieties is one important objective of rice breeding programs. Several genes related to male sterilities, restores, and pollinators have been identified through map-based gene cloning within natural variations of rice. These identified genes are good targets for introducing genetic traits in molecular breeding. This study was conducted to breed elite hybrid lines with major genes related to hybrid traits and disease/insect resistance in 240 genetic resources and F1 hybrid combinations of rice. Molecular markers were reset for three major hybrid genes (S5, Rf3, Rf4) and thirteen disease/insect resistant genes (rice bacterial blight resistance genes Xa3, Xa4, xa5, Xa7, xa13, Xa21; blast resistance genes Pita, Pib, Pi5, Pii; brown planthopper resistant genes Bph18(t) and tungro virus resistance gene tsv1). Genotypes were then analyzed using molecular marker-assisted selection (MAS). Biological assay was then performed at the Red River Delta region in Vietnam using eleven F1 hybrid combinations and two control vatieties. Results showed that nine F1 hybrid combinations were highly resistant to rice bacterial blight and blast. Finally, eight F1 hybrid rice varieties with resistance to disease/insect were selected from eleven F1 hybrid combinations. Their characteristics such as agricultural traits and yields were then investigated. These F1 hybrid rice varieties developed with major genes related to hybrid traits and disease/insect resistant genes could be useful for hybrid breeding programs to achieve high yield with biotic and abiotic resistance.

Research paper thumbnail of Mapping quantitative traits for grain physical and textural quality in Cambodian Jasmine rice PRD

Euphytica, 2019

Grain physical and textural traits are key parameters that are assessed in rice quality improveme... more Grain physical and textural traits are key parameters that are assessed in rice quality improvement programs. In order to dissect the genetic basis of the premium Cambodian quality rice Phka Rumduol (PRD), a population including more than 300 recombinant inbred lines derived from PRD and Thmar Krem was used to map quantitative trait loci (QTLs) for grain length (GL), grain width (GW), degree of chalkiness, grain translucency and texture-associated traits including amylose content (AC), gelatinisation temperature (GT), gel consistency and pasting properties derived from a rapid visco analyser. QTL analysis revealed large-effect QTLs and minor QTLs for these traits of quality, indicating a complex interplay between major and minor genes. The QTL located on chromosome 3 is the major locus for GL, and the one on chromosome 5 plays a major role in determining GW. A novel QTL for GL was identified on the short arm of chromosome 6 and explained about 20% of the phenotypic variation in GL. Grain translucency and chalkiness were largely controlled by QTLs on chromosome 5 and 6. Putative genes for texture-associated traits relate back to the starch biosynthesis pathways. Major QTLs for AC and GT colocalised to the Waxy and starch synthase IIa genes on chromosome 6, respectively. Minor QTLs on chromosomes 3 and 8 were identified for AC, setback, peak viscosity and hot-paste consistency, and on chromosomes 4 and 7 for GT and pasting temperature. This is the first QTL mapping study for the quality of Cambodian rice.

Research paper thumbnail of Application and utilization of marker assisted selection for biotic stress resistance in hybrid rice (Oryza sativaL.)

Journal of Plant Biotechnology, 2016

Development of disease resistant plant is one of the important objectives in rice breeding progra... more Development of disease resistant plant is one of the important objectives in rice breeding programs because biotic stresses can adversely affect rice growth and yield losses. This study was conducted to identify lines with multiple-resistance genes to biotic stress among 173 hybrid rice breeding lines and germplasms using DNA-based markers. Our results showed that one hybrid rice line [IR98161-2-1-1-k1-3 (IR86409-3-1-1-1-1-1/IRBB66)] possessed 5 bacterial blight resistance genes (Xa4, xa5, Xa7, Xa13 and Xa21) while two hybrid rice lines [IR98161-2-1-1-k1-2 (IR86409-3-1-1-1-1-1/IRBB66) and 7292s (IR75589-31-27-8-33S(S1)/ IR102758B)] possessed 3 bacterial blight resistance genes (Xa4, Xa7 and Xa21, and Xa3, Xa4 and xa5). Molecular survey on rice blast disease revealed that most of these lines had two different resistant genes. Only 11 lines possessed Pib, Pi-5, and Pi-ta. In addition, we further surveyed the distribution of insect resistant genes, such as Bph1, Bph18(t), and Wbph. Three hybrid breeding lines [

Research paper thumbnail of Current Applicable DNA Markers for Marker Assisted Breeding in Abiotic and Biotic Stress Tolerance in Rice (Oryza sativa L.)

Plant Breeding and Biotechnology, 2016

Abiotic and biotic stresses adversely affect rice (Oryza sativa L.) growth and yield. Conventiona... more Abiotic and biotic stresses adversely affect rice (Oryza sativa L.) growth and yield. Conventional breeding is a very effective method to develop tolerant rice variety; however, it takes a decade long to establish a new rice variety. DNA-based markers have a huge potential to improve the efficiency and precision of conventional plant breeding via marker-assisted selection (MAS). The large number of quantitative trait loci (QTLs) mapping studies for rice has provided an abundance of DNA marker-trait associations. The limitations of conventional breeding such as linkage drag and lengthy time consumption can be overcome by utilizing DNA markers in plant breeding. The major applications of DNA markers such as MAS, QTL mapping and gene pyramiding have been surveyed. In this review, we presented the latest markers available for some of the most important abiotic and biotic stresses in rice breeding programs. Achieving a significant impact on crop improvement by marker assisted breeding (MAB) represents the great challenge for agricultural scientists in the next few decades.

Research paper thumbnail of Quality evaluation, fatty acid analysis and untargeted profiling of volatiles in Cambodian rice

Research paper thumbnail of Breeding Hybrid Rice with Genes Resistant to Diseases and Insects Using Marker-Assisted Selection and Evaluation of Biological Assay

Plant Breeding and Biotechnology, 2019

Developing elite hybrid rice varieties is one important objective of rice breeding programs. Seve... more Developing elite hybrid rice varieties is one important objective of rice breeding programs. Several genes related to male sterilities, restores, and pollinators have been identified through map-based gene cloning within natural variations of rice. These identified genes are good targets for introducing genetic traits in molecular breeding. This study was conducted to breed elite hybrid lines with major genes related to hybrid traits and disease/insect resistance in 240 genetic resources and F1 hybrid combinations of rice. Molecular markers were reset for three major hybrid genes (S5, Rf3, Rf4) and thirteen disease/insect resistant genes (rice bacterial blight resistance genes Xa3, Xa4, xa5, Xa7, xa13, Xa21; blast resistance genes Pita, Pib, Pi5, Pii; brown planthopper resistant genes Bph18(t) and tungro virus resistance gene tsv1). Genotypes were then analyzed using molecular marker-assisted selection (MAS). Biological assay was then performed at the Red River Delta region in Vietnam using eleven F1 hybrid combinations and two control vatieties. Results showed that nine F1 hybrid combinations were highly resistant to rice bacterial blight and blast. Finally, eight F1 hybrid rice varieties with resistance to disease/insect were selected from eleven F1 hybrid combinations. Their characteristics such as agricultural traits and yields were then investigated. These F1 hybrid rice varieties developed with major genes related to hybrid traits and disease/insect resistant genes could be useful for hybrid breeding programs to achieve high yield with biotic and abiotic resistance.

Research paper thumbnail of Mapping quantitative traits for grain physical and textural quality in Cambodian Jasmine rice PRD

Euphytica, 2019

Grain physical and textural traits are key parameters that are assessed in rice quality improveme... more Grain physical and textural traits are key parameters that are assessed in rice quality improvement programs. In order to dissect the genetic basis of the premium Cambodian quality rice Phka Rumduol (PRD), a population including more than 300 recombinant inbred lines derived from PRD and Thmar Krem was used to map quantitative trait loci (QTLs) for grain length (GL), grain width (GW), degree of chalkiness, grain translucency and texture-associated traits including amylose content (AC), gelatinisation temperature (GT), gel consistency and pasting properties derived from a rapid visco analyser. QTL analysis revealed large-effect QTLs and minor QTLs for these traits of quality, indicating a complex interplay between major and minor genes. The QTL located on chromosome 3 is the major locus for GL, and the one on chromosome 5 plays a major role in determining GW. A novel QTL for GL was identified on the short arm of chromosome 6 and explained about 20% of the phenotypic variation in GL. Grain translucency and chalkiness were largely controlled by QTLs on chromosome 5 and 6. Putative genes for texture-associated traits relate back to the starch biosynthesis pathways. Major QTLs for AC and GT colocalised to the Waxy and starch synthase IIa genes on chromosome 6, respectively. Minor QTLs on chromosomes 3 and 8 were identified for AC, setback, peak viscosity and hot-paste consistency, and on chromosomes 4 and 7 for GT and pasting temperature. This is the first QTL mapping study for the quality of Cambodian rice.

Research paper thumbnail of Application and utilization of marker assisted selection for biotic stress resistance in hybrid rice (Oryza sativaL.)

Journal of Plant Biotechnology, 2016

Development of disease resistant plant is one of the important objectives in rice breeding progra... more Development of disease resistant plant is one of the important objectives in rice breeding programs because biotic stresses can adversely affect rice growth and yield losses. This study was conducted to identify lines with multiple-resistance genes to biotic stress among 173 hybrid rice breeding lines and germplasms using DNA-based markers. Our results showed that one hybrid rice line [IR98161-2-1-1-k1-3 (IR86409-3-1-1-1-1-1/IRBB66)] possessed 5 bacterial blight resistance genes (Xa4, xa5, Xa7, Xa13 and Xa21) while two hybrid rice lines [IR98161-2-1-1-k1-2 (IR86409-3-1-1-1-1-1/IRBB66) and 7292s (IR75589-31-27-8-33S(S1)/ IR102758B)] possessed 3 bacterial blight resistance genes (Xa4, Xa7 and Xa21, and Xa3, Xa4 and xa5). Molecular survey on rice blast disease revealed that most of these lines had two different resistant genes. Only 11 lines possessed Pib, Pi-5, and Pi-ta. In addition, we further surveyed the distribution of insect resistant genes, such as Bph1, Bph18(t), and Wbph. Three hybrid breeding lines [

Research paper thumbnail of Current Applicable DNA Markers for Marker Assisted Breeding in Abiotic and Biotic Stress Tolerance in Rice (Oryza sativa L.)

Plant Breeding and Biotechnology, 2016

Abiotic and biotic stresses adversely affect rice (Oryza sativa L.) growth and yield. Conventiona... more Abiotic and biotic stresses adversely affect rice (Oryza sativa L.) growth and yield. Conventional breeding is a very effective method to develop tolerant rice variety; however, it takes a decade long to establish a new rice variety. DNA-based markers have a huge potential to improve the efficiency and precision of conventional plant breeding via marker-assisted selection (MAS). The large number of quantitative trait loci (QTLs) mapping studies for rice has provided an abundance of DNA marker-trait associations. The limitations of conventional breeding such as linkage drag and lengthy time consumption can be overcome by utilizing DNA markers in plant breeding. The major applications of DNA markers such as MAS, QTL mapping and gene pyramiding have been surveyed. In this review, we presented the latest markers available for some of the most important abiotic and biotic stresses in rice breeding programs. Achieving a significant impact on crop improvement by marker assisted breeding (MAB) represents the great challenge for agricultural scientists in the next few decades.