Jeom-Ho Lee

QTL Detection Associated with Eating Quality Based on Palatability Test in Japonica Rice (Oryza sativa L.)

A recombinant inbred line (RIL) population derived from the cross between Ilpumbyeo (a Japonica of high eating quality) and Moroberekan (a tropical Japonica type of low eating quality) was used for mapping QTLs associated with grain physicochemical properties and eating quality traits in rice. A total of 182 recombinant inbred lines were evaluated for two physicochemical traits, alkali digestive value and amylose content, and five traits associated with eating quality including glossiness of cooked rice determined by Toyo-taste meter, and glossiness, stickiness, hardness and overall evaluation for taste evaluation by panels. A total of 30 QTLs associated with seven traits in 10 loci on chromosomes 1, 3, 5, 6, 10, and 12 were identified. The most critical regions for eating quality were on chromosomes 3, 5 and 6 by Ilpumbyeo alleles, whereas Moroberekan contributed a total of 6 loci on chromosomes 1, 10 and 12. The QTL region on chromosome 5 contains the novel alleles for eating quality from Ilpumbyeo. MAS using DNA markers tightly linked with those QTLs will be useful for breeding Japonica cultivars with high eating quality.

Development of multi-resistant lines to brown planthopper, bacterial blight, and rice stripe virus using anther culture in rice.

This study was conducted to develop multi-resistant lines to brown planthopper, bacterial blight, and rice stripe virus using anther culture in rice. A total of 213 double haploid lines were developed the cross between HR26234-12-1-1 conferring resistant to bacterial blight and rice stripe virus and SR30071-3-7-23-6-2-1-1 conferring resistant to brown planthopper, bacterial bight, and rice stripe virus. Using DNA molecular marker, HR26234 and SR30071 were confirmed to have Xa3+xa5+Stvb-i and Bph18+Xa4+Stvb-i, respectively. All double haploid lines carried Stvb-i, and Bph18+Xa3, Bph18+Xa4, Bph18+Xa3+xa5, Bph18+Xa4+xa5, bph18+Xa3, bph18+Xa4, bph18+Xa3+xa5, and bph18+Xa4+xa5 combinations were identified. Segregation distortions such as no combinations carrying Bph18(or bph18)+xa5+Stvb-i and fewer lines carrying Bph18 than bph18 were occurred in DH population. Brown planthopper resistant lines carrying Bph18 showed longer culm length than susceptible lines. Selected Bph18+Xa4+xa5+Stvb-i combination lines with short culm conferred resistant to brown planthopper, bacterial blight, and rice stripe virus, while showed deleterious effects such as spikelet sterility, lower yield, and vulnerable to lodging than standard and comparative varieties. Using anther culture, we rapidly developed multi-resistant lines to brown planthopper, bacterial blight, and rice stripe virus. However, distorted segregation in DH population and linkage drag with Bph18 were obstacles to develop practical multi-resistant cultivars.

Development of breeding lines for early maturing glutinous japonica rice carrying bacterial blight resistance genes, Xa2, Xa3, xa5, and Xa21.

This study was conducted to develop breeding lines carrying bacterial blight resistance genes, Xa2, Xa3, xa5, and Xa21 for enhancing the resistance of early maturing glutinous japonica rice. Resistant lines were developed by backcrossing into early maturing glutinous elite cultivar, Sangjuchalbyeo and phenotypic selection for bacterial blight resistance and agronomic traits. Selected lines were confirmed the incorporation of the resistance genes using DNA markers and evaluated the resistance reaction against four Korean and eleven Philippine bacterial bight races. HR24465 line carrying Xa2 was resistant to Korean races K1, K2, and Philippine race 9a. HR24666 line carrying Xa3 was moderately resistant or resistant to races except for Korean race K3a and Philippine race 6. Resistant lines carrying xa5 were resistant to all races except for Philippine race 6. HR24669 line carrying Xa21 was moderately resistant or resistant to races except for Korean race K1 and Philippine race 10. Yield-related traits of breeding lines exhibited similar characteristics to Sangjuchalbyeo. These resistant lines could be useful breeding materials for improving the resistance of early maturing glutinous japonica rice against Xanthomonas oryzae pv. oryzae.

A high biomass yield and whole crop silage rice cultivar 'Mogyang'.

‘Mogyang’, a new high biomass yield and whole crop silage rice (Oryza sativa L.) cultivar, is developed by the rice breeding team of National Institute of Crop Science, R.D.A., Suwon, Korea, during the period from was to 2010 and released in 2011. It was derived from a cross between SR24592-HB2319/IR73165-B-6-1-1. This cultivar has about 118 days of growth duration from seeding to heading and has long and erect leaves (culm length 93 cm). It has tough thick culm with strong lodging tolerance. This cultivar has a few less tillers per hill and markedly more spikelet numbers per panicle. ‘Mogyang’ has wide and stay green leaf compared other whole crop silage varieties. This new variety has grain shattering resistance and disease resistance for blast and dwarf virus. This variety has good qualities for whole crop silage with high TDN (Total Digestive Nutrient) yield and low NDF (Neutral Detergent Fiber) and low ADF (Acid Detergent Fiber) compared to common high grain yield varieties. The biomass and TDN yield performance of ‘Mogyang’ was 59.5% (chemical properties), 17.7 MT/ha (biomass yield), individually in local adaptability test for three years. ‘Mogyang’ is adaptable to central plain area, southern plain area of Korea.

A Late-Maturing and Whole Crop Silage Rice Cultivar `Mogwoo`

`Mogwoo`, a new high yield and whole crop silage rice (Oryza sativa L.) cultivar, was developed by the rice breeding team of the National Institute of Crop Science, RDA, Suwon, Korea, from 1999 to 2009, and was released in 2010. It was derived in 1999 from a cross between Dasanbyeo, having a high yield, and Suweon431/IR71190-45-2-1. A promising line, SR25848-C99-1-2-1, selected by the pedigree breeding method, was designated the name of `Suweon 519` in 2007. This cultivar has about 155 days of growth period from seeding to heading, and is tolerance to lodging, with erect pubescent leaves as well as a long and thick culm. This cultivar has the same number of tillers per hill and higher spikelet numbers per panicle compared to Nokyang. `Mogwoo` has longer leaves compared with other Tongil-type varieties. This new variety is resistant to grain shattering, leaf blast, bacterial leaf blight, and small brown planthopper. The biomass yield of `Mogwoo` was 1,956 kg/10a in a regional test over three years. The result shows that `Mogwoo` is adaptable to central and south-east plain areas of Korea.

Multiple Disease Resistant Early Maturing Rice Cultivar 'Joil' with High Grain Quality Adaptable to Early Transplanting Cultivation in the Southern Plain Area

Joil’ is a multiple disease resistant early maturing rice cultivar with high grain quality. ‘Joil’ was derived from a single cross between ‘Unbong37’ (cultivar name ‘Unmi’) and ‘HR23156-26-2-3-5’. ‘Unmi’ is an early maturing rice cultivar with high grain quality and resistance to rice blast and stripe virus. ‘HR23156-26-2-3-5’ is an early maturing elite rice line with lodging resistance and cold tolerance. ‘Joil’ was selected through the pedigree method, yield trials, and local adaptability tests. ‘Joil’ was an early maturing rice. The heading date of ‘Joil’ was July 16 in early transplanting cultivation, which was 2 days later than that of ‘Jopyeong’. ‘Joil’ was a lodging resistance rice with a short culm and showed better tolerance to viviparous germination than that of ‘Jopyeong’. ‘Joil’ was a multiple disease resistant rice with resistance against rice blast, bacterial blight, and stripe virus. ‘Joil’ showed higher yield in both early and late-transplanting cultivations than those of the standard rice cultivars ‘Jopyeong’ and ‘Geumo’. ‘Joil’ had enhanced grain quality under high temperature ripening conditions in early transplanting cultivation. The cooked rice had good grain appearance and taste attributes, and this cultivar had a higher head rice ratio than that of ‘Jopyeong’. ‘Joil’, a multiple disease resistant early maturing rice cultivar with high grain quality, would be suitable for early transplanting cultivation in the southern plain area (Registration No. 6792).

Lodging and Pre-harvest Sprouting Tolerant, High Quality and Suitable for Processing Cooked Rice ‘Jungmo1017’

The ‘Jungmo1017’ is a japonica rice variety developed from a cross between Suweon462 which has a good plant architecture, cold tolerance, moderately tolerant to leaf blast and bacterial blight and medium maturing habit, and Yeongdeog34 which has translucent milled rice and good milling properties, by the rice breeding team at NICS, RDA in 2011. The heading date of ‘Jungmo1017’ is August 16 and it is six days later than ‘Hwaseong’. ‘Jungmo1017’ has 65 cm of culm length which is 18 cm shorter than those of ‘Hwaseong’ and 93 spikelet per panicle. The pre-harvest sprouting rate of ‘Jungmo1017’ is 8.6% that is lower than 27.7% of ‘Hwaseong’ on local adaptability test (LAT). It showed resistance to blast diseases and moderately resistant to bacterial blight (K1 race) and stripe virus, but susceptible to other races (K2, K3 and K3a) of bacterial blight, viruses and planthoppers. The milled rice of this variety exhibits translucent, clear non-glutinous endosperm and medium short grain shape. It has better palatability index of cooked rice (0.53) than that of ‘Hwaseong’. ‘Jungmo1017’ showed lower protein content (6.4%) and amylose content (18.0%). ‘Jungmo1017’ could use aseptic-packaged cooked rice or processing cooked rice because its hardness of cooked rice is soft, setback and balance is low and palatability of cold and aseptic rice showed high score. The characters related to milling is better than those of ‘Hwaseong’. ‘Jungmo1017’ showed 5.01 MT/ha of milled rice productivity at 7 sites of middle plain, southern mid-mountainous and south-east coastal area in ordinary cultivation. ‘Jungmo1017’ could be adaptable to the middle plain area in Korea.

A Medium-Maturing, Black Pericarp and Aromatic Rice Variety ‘Sheonhyangheukmi’

Sheonhyangheukmi, black pericarp and aromatic rice (Oryza sativa L.) variety, was developed by the rice breeding team of National Institute of Crop Science (NICS), RDA in 2011. This variety was derived from the cross between Suweon477 and CG2-2-75-4-1-22-3 in 2002 summer season, and selected by a promising line, SR28684-9-2-2-2, was selected and designated as the line of Suweon532 in 2009. The local adaptability test of Suweon532 was carried out from 2009 to 2011 and it was named as Sheonhyangheukmi in 2011. This variety is medium matured with heading date of August 11 in central plain area of Korea. This variety is about 89 cm tall culm length and 122 spikelets per panicle. Its 1,000 grain-weight of brown rice is 17.0 g. This variety is susceptible to leaf blast and and insect pest, but resistant to bacterial leaf blight and moderately resistant to stripe virus disease. This variety has tolerance to unfavorable environment such as cold. Milled rice of Sheonhyanghuekmi is non-glutinous and aromatic endorsperm. This variety has higher anthocyanin content compared to black pigmented variety Heukjinju. The yield potential of Sheonhyangheukmi in brown rice was about 4.75 MT/ha at ordinary fertilizer level in local adaptability test for three years. This variety would be adaptable to the southern plain and middle plain of Korea.