Plant & Animal Genome VI Conference Plant & Animal Genome VI Conference
P89
School of Biological Sciences, University of Birmingham, Edgbaston, Birmingham B15 2TT, UK
Our preliminary results have shown that the AFLP molecular marker
system can be successfully employed for studying genetic variation in
avocado. The amplification products from two primer pair combinations
E-AT/M-CAA and E-AT/M-CAC were too complex to score, while three
selective nucleotides selection at both the ends resulted in sharp
scorable bands for 18 accessions. We extracted DNA from two different
samples of one accession to test the reliability of AFLP fingerprints
and to our satisfaction we obtained identical banding patterns from
these two samples. A large number of polymorphic bands (184) were
scored for these accessions utilising the four primer pair combinations.
To analyse similarity among the avocado accessions we
assumed that each AFLP amplification product represented a dominant
allele at a locus. Genetic similarities were computed using the simple
matching coefficient and the resultant matrix was subjected to cluster
analysis by the UPGMA method, which yielded a dendrogram displaying
relationships between accessions. All but one accession fell into two
or three subgroups. The first are all Mexican in origin, while five of
the seven accessions in a second subgrouping were derived from the
Canary Islands. It is uncertain whether those accessions falling into
a putative third subgrouping and suggesting a degree of genetic
similarity, represent a significant common ancestry.