12. Alcohol dehydrogenase isozyme in rice (Oryza sativa complex)
  H.S. SUH, L.J. CHEN and D.S. LEE

College of Natural Resources, Yeungnam University, Kyongsan 712-749, Korea

To investigate alcohol dehydrogenase (Adh, E.C. isozyme variability in Oryza sativa complex for environmental stress tolerance, Adh1 locus was assayed by starch-gel (system H, Tris-citric pH 7.6) methods (Glaszmann et al. 1988). A total of 92 rice strains consisting of Oryza sativa, Oryza rufipogon, and Oryza barthii from worldwide distribution were studied. Enzyme extracts were prepared from 1-5 shoots, 2-4 days after germination at 32oC in incubator. The stained bands were read using the systems suggested by Morishima and Glaszmann et al. (1990).

Table 1 summarizes distribution of four alleles of Adh1 in Oryza sativa complex. Polymorphism for three alleles (Adh1-1, Adh1-2, and Adh1-3) was not observed within the groups of lowland rice and Oryza rufipogon, it suggested that there is no indica-japonica differentiation at Adh1 locus in lowland rice as well as in Oryza rufipogon. By contrast,

polymorphism for two alleles (Adh1-1 and Adh1-2) was observed in upland rice. It implied that upland rice is more adaptable to diverse environments, and may play important role in indica-japonica differentiation. Among the strains investigated, only one Pakistan rice variety, Basmati 385, possessed the Adh1-3 allele, and only the Chinese weedy rice strain Lu-tao possessed the null allele, Adh1-0 (Fig. 1).

Adh is believed to associated with environmental stress such as cold and drought tolerance, thus, some desirable traits of upland rice are probably associated with isozyme markers of Adh1-2. This study provided information for environmental stress tolerance research.


Glaszmann, J.C., B.G. de los Reyes and G.S. Khush, 1988. Electrophoretic variation of isozymes in plumules of rice (Oryza sativa L.)- a key to the identification of 76 alleles at 24 loci. IRRI Res. Paper Series. 134: 14.

Morishima, H. and J.C. Glaszmann, 1990. Current status of isozyme gene symbols. RGN 7: 50-57.