THERMAL ADAPTIVE SIGNIFICANCE OF ADH AND EST-6 ALLOZYMES IN INDIAN GEOGRAPHICAL POPULATIONS OF DROSOPHILA-MELANOGASTER

Indian geographical populations of Drosophila melanogaster exhibit sig nificant correlation (r greater than or equal to 0.95) of allelic freq uencies at Est-6 and Adh loci with latitude as well as altitude. Est-6 (S) and AdhF allozymes are well adapted to colder environments while E st-6(F) and AdhS are warm adapted. The data on allozymic dines match c limatic conditions on the Indian subcontinent. On the basis of multipl e regression analysis, one major conclusion is that coefficient of var iation of temperature (T-cv) along latitude/altitude accounts for alte rations in allelic frequency at the Adh locus while T-max and T-min ex plain changes at the Est-6 locus. Thus, climatic conditions lead to th ermal selection of allozymes in Indian populations of D. melanogaster.