Use of Androgenesis in Haploid Breeding

Yi, Gihwan,Kim, Kyung-Min,Sohn, Jae-Keun Institute of Agricultural Science and Technology 2013 慶北大農學誌 Vol.31 No.2

Haploids are plants with a gametophytic number of chromosomes in their sporophytes. Androgenesis occurs from asymmetric division of pollen grains into generative cells and vegetative cells, followed by re-entry of the vegetative cell during S-phase, which causes microspores progress into G2/M transition in culture. One of the most interesting features of haploids is the possibility to produce doubled haploid (DH) individuals. Doubled haploidy is extremely useful to plant breeders because it enables shortened breeding periods and efficiency in selection of useful recessive agronomic traits. Doubled-haploid technology is not only applicable to breeding, but also to transformation programs of desired genes. In addition to practical breeding programs, DH lines provide useful materials of fundamental genetics including exploitation of QTLs and genes conferred with various agronomic traits by establishing DH populations. This paper provides historical overviews on androgenesis and describes several mechanisms associated with pollen embryogenesis, including mode of actions in pollen embryogenesis, mechanisms of chromosome doubling and factors affecting androgenesis. We also discuss recent progress in application of haploids to breeding, genes associated with in vitro response and drawbacks to anther culture for application of doubled haploids in crop breeding.

Rapid and Simple Procedure for Homogenizing Leaf Tissues Suitable for Mini‐Midi‐Scale DNA Extraction in Rice

Yi, Gihwan,Choi, Jun‐,Ho,Lee, Jong‐,Hee,Jeong, Unggi,Nam, Min‐,Hee,Yun, Doh‐,Won,Eun, Moo‐,Young Taylor Francis 2005 Preparative biochemistry & biotechnology Vol.35 No.3

<P>We describe a rapid and simple procedure for homogenizing leaf samples suitable for mini/midi‐scale DNA preparation in rice. The methods used tungsten carbide beads and general vortexer for homogenizing leaf samples. In general, two samples can be ground completely within 11.3±1.5 sec at one time. Up to 20 samples can be ground at a time using a vortexer attachment. The yields of the DNA ranged from 2.2 to 7.6 µg from 25–150 mg of young fresh leaf tissue. The quality and quantity of DNA was compatible for most of PCR work and RFLP analysis.</P>

Improved marker-assisted selection efficiency of multi-resistance in doubled haploid rice plants

Yi, Gihwan,Lee, Hyun-Suk,Kim, Kyung-Min Springer-Verlag 2015 Euphytica Vol.203 No.2

Pedigree Analysis of 17 High Quality Korean Rice Cultivars Using Web Database Systems

Gihwan Yi,Dong-Soo Park,Eun-Sook Chung,Song-Yi Song,Nam-Soo Jeon,Min-Hee Nam,Doh-Hoon Kim,Chang-Deok Han,Moo-Young Eun,Yeon-Chung Ku 韓國作物學會 2006 Korean journal of crop science Vol.51 No.6

It is important to understand pedigree of rice cultivars commonly used for breeding. In this paper, pedigree tables for tracking the pedigree of 17 representative rice cultivars recommended by Rural development Adminstration (RDA) were completed and analyzed using two kinds of web database system; 'IRIS' and 'RRDB'. Seven cultivars, namely, 'Sangmibyeo', 'Ilpumbyeo', 'Saegewhabyeo', 'Surabyeo', 'Shindongjinbyeo', 'Ilmibyeo' and 'Jungwhabyeo' had 'Koshihikari' on the pedigree of their ancestor. Besides 'Koshihikari', the most feguently used ancestral germplasms among the high quality rice cultivars were 'Fujisaka 5', 'Kameno o' and 'Asahi', 'Fujisaka 5' was used as ancestral parent in 12 out of 17 cultivars. Interestingly, 'Kameno o' was used in pedigree of 16 out of 17 high quality varieties and 'Asahi' was used in the ancestral pedigree of all 17 varieties. 'Hwayeongbyeo' was used as one of parent in the breeding of 'Dongjin 1', 'Hwabongbyeo', 'Saegewhabyeo' and 'Junambyeo'. 'Ilpumbyeo' was used in the breeding pathway of 'Junambyeo' and 'Saegewhabyeo', 'Mangeumbyeo' itself was not enlisted as one of high quality rice cultivars, but was used as a breeding parent of three high quality varieties, namely, 'Saegewhabyeo', 'Hwabongbyeo' and 'Nampyeongbyeo'. Incorporated with evaluation data, pedigree will provide a valuable chance to genealogical tracking of agronomic traits such as disease resistance, grain quality and etc.

Use of Androgenesis in Haploid Breeding

Gihwan Yi,Kyung-Min Kim,Jae-Keun Sohn 경북대학교 농업생명과학대학 2013 Current Research on Agriculture and Life Sciences Vol.31 No.2

Haploids are plants with a gametophytic number of chromosomes in their sporophytes. Androgenesis occurs from asymmetric division of pollen grains into generative cells and vegetative cells, followed by re-entry of the vegetative cell during S-phase, which causes microspores progress into G2/M transition in culture. One of the most interesting features of haploids is the possibility to produce doubled haploid (DH) individuals. Doubled haploidy is extremely useful to plant breeders because it enables shortened breeding periods and efficiency in selection of useful recessive agronomic traits. Doubled-haploid technology is not only applicable to breeding, but also to transformation programs of desired genes. In addition to practical breeding programs, DH lines provide useful materials of fundamental genetics including exploitation of QTLs and genes conferred with various agronomic traits by establishing DH populations. This paper provides historical overviews on androgenesis and describes several mechanisms associated with pollen embryogenesis, including mode of actions in pollen embryogenesis, mechanisms of chromosome doubling and factors affecting androgenesis. We also discuss recent progress in application of haploids to breeding, genes associated with in vitro response and drawbacks to anther culture for application of doubled haploids in crop breeding.

Analysis of Low Amylose and Processability Fractured Endosperms Derived from Somatic Variation

Yi, Gihwan,Kim, Kyung Min 'Scientific Research Publishing, Inc.' 2013 Food and nutrition sciences Vol.4 No.6

한국, 터키 및 루마니아에서 국내육성 벼품종의 출수기 및 수량 변이

이기환 ( Gihwan Yi ) 한국국제농업개발학회 2015 韓國國際農業開發學會誌 Vol.27 No.2

We analyze relationships between flowering behaviors and day length of Korean rice cultivars in Turkey and Romania for the reorientation of rice cultivation against climatic change. The longest day light hours of the summer solstice in Romania, Turkey and Korea was 15.5 hours, 15.1 hours and 14.5 hours, respectively. Average flowering date of early maturing cultivars was July 28 in Korea, August 8 in Turkey and September 7 in Romania. Days to heading were 27days late in Romania compare to that of Korea. ‘Goun’ showed the least difference and ‘Hanarum’ showed the largest difference in flowering date in Turkey among the cultivars. Although varietal differences were admitted, day light hours that transition from Basic Vegetative Period to Reproductive Period ranged fourteen hours thirty minute to fifteen hours ten minute regardless growth duration of tested cultivars. Tongil type rice ‘Samgang’ showed minimum difference in days to heading in all tested locations with 5days difference. It is suggest that ‘Samgang’ have wide adaptability in the sense of flowering behaviors in medium to high latitude regions such as Turkey and Romania.

벼 종피색 변이체에 대한 항산화 활성 분석과 미립특성

이기환(Gihwan Yi),이현숙(Hyun-Suk Lee),손재근(Jae-Keun Sohn),김경민(Kyung-Min Kim) 한국생명과학회 2012 생명과학회지 Vol.22 No.12

벼(Oryza sativa L.)에서 Insertional 유래 MGI079 돌연변이 계통의 자색미에 대한 항산화 활성을 보기 위하여 폴리페놀, 플라보노이드, DPPH radical, 안토시아닌 및 색차계를 이용하여 분석하였다. 폴리페놀 함량에서 MGI079-2-1와 MGI079-2-6은 MGI079보다 1.3배에서 1.9배 이상 증가되었고, 플라보노이드에는 MGI079-2-1 MGI079보다 6.4배 이상 증가되었다. DPPH 자유기에는 MGI079-2-1이 MGI079보다 24.4배 이상 항산화력이 증대되었다. 안토시아닌 성분에는 MGI079- 2-6은 MGI079보다 106.4배 이상 증가되었으며 흑남에 비해서는 1.4배 증가하였다. 색차계에서 Hunter’s 값(L, a, b)은 안토시아닌(-5.64**, 5.21**와 -1.15)의 L, a에서 유의성이 있는 것으로 보였다. MGI079 돌연변이 계통의 미립 장폭비는 MGI079에 비해서 medium과 bold type으로 분리되었으며, 천립중은 MGI079 (19.8 g)보다 돌연변이 계통들이 13.6~19.6 g으로 감소하였다. 아밀로스는 MGI079 보다 5.6~23.8% 증가하였고, 배유의 전분립 형태는 비정형 전분립 특성 등 차이를 보였다. Insertional 유래 MGI079 돌연변이 계통들의 항산화 활성 분석에서 MGI079-2-1와 MGI079-2-6은 MGI079와 흑남보다 항산화력이 높은 기능적 가치로 미립특성과 관련하여 색소 자원의 개발뿐만 아니라 신품종 육성에 필요한 예비품종으로 실용화가 기대된다. This study examined the antioxidant activity of the dark purple rice seeds from the rice line, MGI079, derived from insertional mutagenesis. The contents of polyphenolic compounds were 1.3 and 1.9-fold higher in the MGI079-2-1 and MGI079-2-6 rice lines than in the donor cultivar MGI079. Flavonoid contents were 6.4-fold higher in the MGI079-2-1 line. The MGI079-2-1 line showed a 24.4-fold higher activity in DPPH free radical scavenging compared to the MGI079 line. The anthocyanin content of the MGI079- 2-6 line was more than 106.4-fold higher than the MGI079 line and 1.4-fold higher than the Heugnam line. Anthocyanin content in colored rice grains was negatively correlated with Hunter’s L, a, and b values, with the correlation coefficients of -5.64**, 5.21** and -1.15, respectively. The grain length/width of a mutant of MGI079 segregated to a medium and bold type compared to the medium type of MGI079. However, the 1,000 grain weight was decreased to 13.6~19.6 g compared to 19.8 g for MGI079. Amylose content of the endosperm was 5.6~23.8% higher than in the MGI079 line. The grain of mutants of MGI079 was distinguished by its starch characteristics. The higher antioxidant activity of the MGI079-2-1 and MGI079-2-6 lines indicated functional characteristics associated with high-value resources, so future breeding should focus on the development of pigments in colored rice in new varieties.

Studies on the optimum screening time for improved WBPH-associated QTL analysis in rice

Soheap Yun,Hyun-Suk Lee,Gihwan Yi,Kyung-Min Kim 한국육종학회 2014 한국육종학회 심포지엄 Vol.2014 No.07

The whitebacked planthopper(WBPH), Sogatella furcifera is a serious pest of rice. The nymphs and adults suck phloem sap which causes reduced plant vigor, stunting, yellowing of leaves, delayed tillering in rice. This study was conducted to identify the optimum screening time for improved WBPH-associated QTL analysis and to develop the markers for use in breeding WBPH resistance. Resistance after 7 days infestation was observed in 100 lines(83.3%), after infestation for 14 days, resistance was observed in 14 lines(11.7%), and after infestation for 21 days, resistance was observed in 10 lines(8.3%). However, no after 14 days infestation was as similar as normal distribution in WBPH resistance. QTLs associated of the resistance detected in four regions on qWBPH1 and qWBPH8 in the intervals marker. After 7 days of infestation, the qWBPH1 was located in the interval RM3482-RM11966 and RM3709-RM11694 with LOD 4.0 and RM3709-RM11694 with LOD 3.5. After 14 days of infestation, The qWBPH1 was located in the interval RM3709-RM11694 with LOD 3.3. and RM3709-RM11694 with LOD 3.3. After 21 days of infestation, The qWBPH8 was located in the interval RM17699 with LOD 3.3. The QTLs on chromosome 1 was the most effective RM11694-RM11669 (LOD 3.3, variance 30%). The resistance lines were collected 10 plants of phenotye variation with genotype. The ratios of coincidence were used to determine resistance in 10 plants with phenotypic variation and a genotype of 8 markers. 3 markers were used: RM3482 on chr.1 represented 100%, RM8235 and RM11694 represented 80%, 90%, respectively, RM17699 on chr.8 represented 80% of the coincident ratio. These selected markers will be useful to rice breeding programs interested in new sources of WBPH resistance

QTLs for detecting DNA markers related to alkali digestion value in rice grain using doubled haploid population

Hyun-Suk Lee,Gyu-Ho Lee,A-Ra Cho,Gihwan Yi,Kyung-Min Kim 한국육종학회 2015 한국육종학회 심포지엄 Vol.2015 No.07

Improving rice high-quality potential is to suffice the food demand of the rapid decreasing consumption, and is a major breeding target recently. We calculated the alkali digestion value (ADV), used to indirectly measure gelatinization temperature, to evaluate the quality of cooked rice in 2013 and 2014. The ADV score of frequency distribution was higher milled rice than brown rice. In total, nine different quantitative trait loci (QTLs) were found on chromosomes1, 3, 5, 6 and 8 in 2013 and 2014. Also, chromosome 5, 8 were detected over two years. The polymorphism using RM223, RM3530, and RM18130 markers can be used to select lines that have a good trait for breeding of high-quality rice. We conclude that selected molecular markers from this QTL analysis could be exploited in future rice quality.