Abstract
Electrophoretic analyses of 19 loci affecting 12 enzymes in 17 Nepali and 11 Indian populations of common buckwheat were conducted by horizontal starch gel electrophoresis. Most of the populations were polymorphic at the loci Adh, Dia-2, Got-2, Mdh-1, Mdh-3, Pgm-2, 6-Pgdh-1 and Sdh-1 and some populations were also polymorphic at the Got-1 and Gdh loci. The populations from Nepal and West Bengal maintained slightly more variability than the average of other outcrossing annual plant species. The percentage of polymorphic loci was 39.5% and the average heterozygosity was 0.133. No distinct local differentiation was found among these populations. They had similar genetic constitutions with the populations from southern China. However, distinct allelic frequencies at some loce were observed in Almora and Rishikesh, both in Uttar Pradesh, India. The Kashmirian populations had less genetic variability and they were quite different from the others. They had lost the variant alleles at the loci Adh, Dia-2, 6-Pgdh-1 and Pgm-2, probably during the spread of cultivation. The processes that might have led to the prsent geographical pattern of allozyme variability are discussed.
