41. Silent allele for Amp- 2 found among Sulawesi varieties

Duncan A. VAUGHAN and Amita JULIANO

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

To assist in our understanding of rice biodiversity, we have been studying selected conserved germplasm with passport data. 195 varieties from Sulawesi, Indonesia, were classified by isozymes into indica (isozyme group 1) and japonica (isozyme group VI) ecogeographic races (Table 1) (Glaszmann, 1987).

Of the 66 indica varieties for which cultural type data is available, 58% came from lowland areas and 38% from upland areas. Of the 99 japonica varieties for which cultural type data is available, 22% came from the lowlands and 78% came from the uplands. 30 varieties did not fall exactly into the isozyme groups of Glaszmann (1987) since they did not exhibit any band for aminopeptidase-2 (Amp-2). These varieties, however, for the 12 isozyme loci scored showed more similarity to isozyme alleles associated with japonica varieties. This is the first report of finding varieties with a silent allele at the Amp-2 locus.

Of the 30 varieties silent for aminopeptidase-2, 18 were from the eastern coast of Central Sulawesi in Parigi and Ampibabo districts, 4 were from the western part of Central Sulawesi, 4 ftom South Sulawesi and 8 from Southeast 

Table 1. Varietal classification based on isozymes of 195 varieties from
Sulawesi, Indonesia
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Province of Sulawesi  Indica       Japonica    Silent for Amp-2
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   North               10   (56%)    8  (44%)
   Central             24   (33%)   31  (42%)  18 (25%)
   South               29   (49%)   26  (44%)   4 ( 7%)
   Southeast            3   (7%)    34  (76%)   8 (17%)
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Fig. 1. Sulawesi island showing the 4 provinces.

Sulawesi (Fig. 1). These varieties came from upland areas and have characteristics of bulu varieties.

References

Glaszmann, J.C. 1987. Isozymes and classification of Asian rice varieties. Theor Appl Genet 74: 21-30.