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rocarpa from the villoso-rupestris group in which a
clear separation of populations at specific and sub-
specific rank was not well detectable.

Figure 3. Differentiation of the total diversity in Hs (within Discussion
populations) and Dst (among populations).
From the analysis of allelic presence in our popula-
tions (pop7 to 13). A distance of 0.22 was found tions, 37 alleles were detected. B. rupestris and B.
between B. incana populations. villosa show a more similar composition whereas B.
incana and B. macrocarpa resulted more distinct and
The minimum distance (0.06) between B. rupestris more differentiated. The presence of six exclusive
and B. villosa was found between pop13 and pop3 alleles was a very important remark because it char-
whereas the maximum value (0.29) was found be- acterizes the populations.
tween pop2 and pop12.
The mean value of polymorphic loci ranged be-
The distances between B. incana and B. villosa and tween 18% in B. villosa subsp. bivoniana (pop5) and
between B. incana and B. rupestris were similar (0.29 63% in B. villosa subsp. bivoniana (pop2), B. rupes-
to 0.51). tris subsp. rupestris (pop7) and B. incana (pop14).
The lowest value of polymorphism was found in pop
High values of genetic distance were found also 5 which is the smallest population studied having less
between B. macrocarpa and the other species, ranging than 50 individuals in its natural habitat. The 36%
from 0.20 to 0.46. value obtained for B. macrocarpa (pop16) is similar
to the result obtained by Lazaro and Aguinagalde
The dendrogram (Figure 4), obtained with (1998a) for a population of B. macrocarpa (36.36%).
UPGMA algorithm, on the basis of these distances
showed a great separation of B. incana and B. mac- The average of gene diversity, computed as Nei’s
(H) statistic, is comprised (mean values) between
0.067 and 0.24 although great fluctuations were de-
tected for different loci. The mean values of H are
lower than those obtained by Lanner-Herrera et al.
(1996) for wild populations of B. oleracea from
Spain, France, and Great Britain for which the aver-
age diversity was 0.40. However, as these authors
report, this index gives information on the variation in

Table 6. Matrix of Nei (1972) minimum distance.

Species Item pop1 pop2 pop3 pop4 pop5 pop6 pop7 pop8 pop9 pop10 pop11 pop12 pop13 pop14 pop15

villosa pop2 0.08

pop3 0.17 0.13

pop4 0.19 0.13 0.10

pop5 0.06 0.07 0.18 0.10

pop6 0.26 0.16 0.18 0.16 0.20

rupestris pop7 0.16 0.14 0.14 0.26 0.20 0.23

pop8 0.08 0.09 0.14 0.24 0.11 0.20 0.08

pop9 0.24 0.23 0.16 0.18 0.21 0.11 0.18 0.20

pop10 0.19 0.11 0.09 0.24 0.21 0.16 0.08 0.07 0.19

pop11 0.26 0.14 0.10 0.19 0.25 0.09 0.15 0.16 0.17 0.08

pop12 0.21 0.16 0.17 0.29 0.21 0.21 0.06 0.07 0.16 0.09 0.18

pop13 0.10 0.09 0.06 0.19 0.17 0.21 0.07 0.07 0.18 0.05 0.10 0.11

incana pop14 0.43 0.35 0.33 0.36 0.41 0.39 0.29 0.38 0.33 0.35 0.32 0.36 0.32

pop15 0.51 0.39 0.51 0.47 0.43 0.45 0.49 0.45 0.55 0.45 0.48 0.50 0.50 0.22

macrocarpa pop16 0.26 0.28 0.37 0.43 0.29 0.43 0.26 0.20 0.32 0.34 0.43 0.23 0.30 0.33 0.46