Isozyme classification of Myanmar rice cultivars resistant to bacterial blight

The analysis of five isozyme loci; Pgi-1, Pgi-2, Amp-1, Amp-2, and Amp-3 identified Isozyme types (Isotypes) for the cultivars resistant to bacterial blight (BE) in Myanmar, The results indicated that all the cultivars of Cas 209 group (Xa-10), TKM 6 group (Xa-4), and Mend Ba group (Xa-4 + Xa-IO) belonged to Isotype I, whereas the cultivars of Java 14 group (Xa-3) were in Isotype V. The cultivars of DZ 192 group (xa-5) were classified either into Isotype I or intermediates, These intermediates were considered as an intermediate of Isotype I and Isotype II, The morphological observations revealed that Isotype I of DZ 192 group was different from Isotype I of Cas 209 group and of TKM 6 group, The algorithm survey of Cas 209 group and TKM 6 group found that the most frequent algorithms used in the two groups were different, and that Amp-1(4) was specifically predominant in Cas 209 group, whilst TKM 6 group was consisted of Amp-1(1) only, The distribution of Amp-1(4) had remarkable concordance with the distribution of Cas 209 group in Asia, The cultivars of TKM 6 group tended to involve wider range of phenotypes and the distribution in Asia is also wide, These results indicated that the origin of Cas 209 group and TKM 6 group might be different.