A total of 134 domestic and foreign genetic resources were analyzed for their protein and amino acids contents in order to identify breeding lines with high lysine content to improve nutritional components of rice. The protein contents ranged between 6.7% and 14.8%, with an average of 8.7%. The Dharial mutant-derived lines had relatively high protein content with the highest amino acids content of 130.16 mg/g and the highest lysine content of 3.86 mg/g which is about 5 times higher than that of the parent. In the case of mutant-derived lines with high floury endosperm such as Goami2, Dodamssal, Milyang320 and LA1, the total amino acids content was as low as 72.61-82.0 mg/g; however, lysine content ranged high between 2.64-3.35 mg/g with lysine ratio to the total amino acids was 3.6%-4.1% which is higher than the average lysine content ratio of 3.0%. Furthermore, correlation analysis revealed a very strong positive correlation between the total amino acids and total protein contents. In contrast, lysine content showed no significant correlation neither with total amino acids nor with protein contents. The lysine content of Milyang320, which was grown in 5 regions across Korea was 0.33%, showing an increase of about 22% compared to that recorded in Nampyeong (0.27%). Therefore, these data suggest that lysine content of Milyang320 is controlled genetically and could be serve as a source in high lysine rice breeding program.
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Glutinous rice is a key grain quality trait occupying an important part during rice processing in most rice growing areas. In this study, a gene pyramiding approach was used to introduce two dull genes, responsible for low amylose content, for glutinous rice breeding using marker assisted selection (MAS). The genotyping results revealed that rice cultivar Milyang319 carries both dull genes on chromosome 6, derived from cv. Milky-queen (
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The application of molecular markers in rice breeding facilitates the rapid screening of genotypes in early growth stages without phenotypic assessment. In the present study, we developed and validated high throughput Kompetitive Allele Specific PCR (KASP) assays for rice stripe virus (RSV) resistance genes. The newly developed RSV-KASP markers were compared with the gel-based InDel marker, Indel7. The results of the RSV-KASP assay and the Indel7 analysis were consistent. Due to their high accuracy, time saving attribute, high throughput features, and cost-effectiveness, KASP could be more suitable for RSV genotyping than other methods.
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Biofortification is a cost-effective method for increasing the availability of micronutrients. Rice breeding for high levels of micronutrients is one of the best approaches to solve the problem of malnutrition. In this study, we developed a doubled haploid (DH) population derived from a cross between the rice cultivars 93-11 and Milyang 352 and evaluated QTLs for grain micronutrients and grain shape. Two co-localized QTLs,
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The yield related traits are controlled by multiple quantitative trait loci (QTLs) and influenced by environmental change in rice. We analyzed QTLs for 15 yield related traits using two backcross populations, derived from crosses between IR64 as recurrent parent and Koshihikari as donor parent, through two years. A total of 67 backcross inbred lines (BILs) and 40 chromosome segment substitution lines (CSSLs) were genotyped using 183 SNP markers using a high-throughput genotyping system. Some genomic gaps between markers were identified in two populations. For fifteen traits in this study, 36 major QTLs (mQTLs) for 12 traits and 16 digenic epistatic QTLs (EpQTLs) for culm length were detected in BILs. On the other hand, 17 mQTLs were detected for nine traits in CSSLs. Among them, six mQTLs for grain yield traits were collocated on chromosome 10 in both years. For spikelet fertility, six putative QTLs were detected under high temperature conditions in 2018. The QTLs identified in this study could be used for the development of rice varieties conferring inter-subspecific combinations of yield-related traits.
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