ALLOZYME POLYMORPHISM IN SEEDS COLLECTED FROM A IUFRO-68 DOUGLAS-FIR TEST-PLANTATION

The allozyme polymorphisms in wind-pollinated seeds of Douglas-fir (Ps eudotsuga menziesii (MIRB) FRANCO.) from a IUFRO-68 test-plantation wa s estimated. The seeds were analyzed as a pooled sample from all cone bearing trees originated of 41 populations, from a total of 71 individ ual trees at an age of 23 years, and compared with the parental popula tion studied as individual trees. Twenty-two loci of 13 enzyme systems were analyzed in the megagametophyte of the parental population. Allo zyme variability levels were high. Seventeen of the 22 loci were polym orphic (P = 77,3 % at 0.99 criterion), with mean number of alleles per locus M/L = 2.68, effective number of alleles, Nc = 1.25. For polymor phic loci MIL = 2.94, and Ne = 131. WRIGHT'S fixation index for studie d loci F = -0.007. The average expected hetcrozygosity, based on all i nvestigated 22 loci was He = 0.192. Observed heterozygosity Hob = 0.19 1. In the filial (embryos) population 6 polymorphic loci were investig ated. For these He and Hob was identical, and amounted: 0.267. Fixatio n index F = 0.005 differ from this index, calculated for similar loci in maternal population where it was -0.082. The calculated multilocus outcrossing rate (tm = 0.966) was similar to those reported for natura l stands of Douglas-fir. From the results obtained one can suggest tha t seeds produced on this IUFRO-68 test plantation retained high level of genetic variation and low level of selfing. Previous quantitative w orks in this test plantation and presented results showed that seeds c ollected from the best growing provenances IUFRO-68 field experiment c an serve for local reforestation purposes.