Rice Genetics Newsletter 14(1997) 27

D. Research Notes

1. Varietal Differentiation and Evolution

  1. Fingerprinting of Korean commercial japonica rice cultivars based on AFLP analysis 
Y.C. cho1 , G.B. gregorio2, K.H. kang1, S.N. ahn1, D.S. brar2 and H.P. moon1 1) National Crop Experiincnl Station, PDA, Suwon. 441-100 Rep. of Korea

2) International Rice Research Institute, P.O. Box 933, 1099 Manila, Philippines

 Recently developed, RFLP analysis (Cho et al. 1995; Wang and Tanksley 1989) and PCR-based technique, RAPD analysis (Ahn et al. 1996; Mackill 1995) have been widely adopted to classification of rice germplasm. These techniques were not efficient in fingerprinting studies among japonica rice cultivars having low polymorphism. The japonica cultivars are predominantly grown in temperate regions in Korea, Japan, some regions of China, California in USA, and so on. This study was undertaken to evaluate the efficiency of fingerprinting among japonica cultivars of relatively close relationship by AFLP analysis.

AFLP technique is based on the selective PCR amplification of restriction fragments from a total digest of genomic DNA. AFLP analysis was carried out by using the method of Vos et al. ( 1996) with some modifications and EcoRI/MseI restriction enzyme combination (Cho et al. 1997). The number of bands for each primer pair ranged from 34 to 92 with an average of 68.3 per reaction and the polymorphic bands from 10 to 39 with an average of 21.4. These results were similar to those of Mackill et al. (1995) and Vos et al. (1996). Genetic similarities among 27 japonica rice cultivars by Nei's formular (1987) were 0.819-0.986. Cluster analysis was performed using UPGMA (Sokal and Michener 1958) based on AFLP polymorphisms (Fig. 1). All cultivars revealed a distinct fingerprint at least within 84.5% genetic similarity. Two Korean cultivars, Sobaegbyeo and Odaebyeo derived from the cross Akitsuho/Fuji 269 of Japanese cultivars, clustered together with their parents. Samnambyeo and Hwaseongbyeo also clustered with their parents, Fuji 280 and BL 1. High quality cultivar Ilpumbyeo grouped with its parent Inabawase, and Japanese high grain quality cultivars, Koshihikari and Kinuhikari. Two Korean cultivars (Jinmibyeo, Tamjinbyeo) and three U.S. cultivars (S-202, M-202, M-401) were weakly clustered with the main group, respectively.

The first breeding goal of rice in Korea has been changed to grain quality together with the elevation of the living standard since the middle of 1980s. During that time, about one hundred japonica rice cultivars have been developed for farmers in Korea. Most Korean japonica commercial rice cultivars were developed from the crosses among some japonica high quality cultivars of Japan, because Korean is similar to Japanese for the liking of rice grain quality (Table 1). So, genetic diversity of modern Korean japonica rice cultivars has been reduced due to intensive breeding efforts to develop the varieties of

28 Rice Genetics Newsletter Vol. 14
 
Table 1. Cross combinations of commercial japonica rice cultivars of high quality cultivated in Korea
Varieties Cross combinations Remarks
Sobaegbyeo Akitsuho/Fuji 269 SR5204-37-1 (Suweon 304)
Odaebyeo Akitsuho/Fuji 269 SR5204-39-8-2 (Suweon 303)
Samnambyeo Fuji 280/BL t Suweon 295
llpumbyeo S.295-sv3/lnabawase " " : Fuji 280/BL 1
Hwaseongbyeo Aichi 37/Samnambyeo F1 anther culture
Jinmibyeo lnabawase/SR4048-5-4-6 SR4048 : BL7/Nongbaeg
Cheonmabyeo BL 7/Nongbaeg SR4048-5-4-4-1-3-2
Jinbubyeo Fukuhikari/Hokuriku 109 Flikuhikari : Koshihikari/Fukunishiki
Hoi<uriku109: Todorokiwase/Fuji170
//lnabawase
Donaiinbyeo Kinmaze/Nagdongbyeo -
//Sadominori
Seomiinbyeo Milyang 20/Asominori -
Tamjinbyeo Milyang 20/Asominori HR 769 : Palgeum/TN 1
//HR769/Asominori //Palgweng/TN 1
high yield, high grain quality, and disease and insect resistance (Kim et al. 1994). Although the average percent polymorphism of AFLP markers was not higher than those of RAPD and microsatellite within japonica cultivars (Mackill et al. 1995), it seems that AFLP analysis will be efficiently used to fingerprint among rice germplasm including japonica cultivars having low genetic diversity because the number of polymorphic bands
Research Notes 29
was much higher per gel.

References 

Ahn, S.N., H.W. Park, H.C. Clioi and H.P. Moon. 1996. Fingerprinting of japonica rice cultivars using RAPD

markers. Korean .J. Breed. 28: 178-183. Cho, Y.C., T.Y. Chung and H.S. Suh, 1995. Genetic characteristics of Korean weedy rice (0ryza sativa L.) by RPLP analysis. Euphytica 86:103-110. Cho, Y.C., G.B. Gregorio, K.H. Kang, S.N. Ahn, D.S. Brar and H.P. Moon, 1997. Classification and genetic

diversity analysis of 48 commercial varieties in rice (0ryza sativa L.) based on AFLP. Korean J. Breed.

29 (Suppl. 1 ): 84-85. Kim, K.H., S.Y. Cho, H.P. Moon and H.C. Choi, 1994. Breeding strategy for improvement and diversification of grain quality in rice. Korean J. Breed (S): 1-15. Mackill, D.J., 1995. Classifying japonica rice cultivars with RAPD markers. Crop Sci. 35: 889-894. 

Mackill, D.J., Z. Zhang and E.D. Redona, 1995. Comparison of AFLP, microsatellite and RAPD marker poly

morphism in rice. RGN 12: 245-248.

Nei, M. 1987. Molecular Evolutionary Genetics. Columbia Univ. Press, NY, ppl06-107. 

Sokal, R.R. and C.D. Michener, 1958. A statistical method evaluating systematic relationships. Univ. Kansas

Sci. Bull. 38:1409-1438. Vos, P., R. Hogers, M. Bleeker, M. Reijans, T. van de Lee, M. Homes, A. Frijters, J. Pot, J. Peleman, M.  Kuiper and M. Zabeau, 1995. AFLP: a new technique for DNA fingerprinting. Nucleic Acids Res. 23:4407- 4414. Wang, Z.Y. and S.D. Tanksley,1989. Restriction fragment length polymorphism in Oryza sativa L. Genome

32:1113-1118.