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species (plus P. pratensis and P. compressa) with 333 fragments being polymorphic
(98.52% polymorphism) (Table 2). A representative example of the amplification
products obtained at P. angustifolia genotypes using the primer combination EcoRI-
ACC+Tru1I-CAG is shown in Fig. 5. The number of bands from each primer
combinations ranged from 84 (EcoRI-ACC+Tru1I-CAA) to 159 (EcoRI-ACC+Tru1I-
CAG). In the present study, a wide variation in the number of polymorphic bands (83-
157) and the percentages of polymorphic bands within a primer combination (98.80-
98.74 %) were observed. The mean polymorphic rate was 98.47 %.
Table 2: The number of bands and degree of polymorphism revealed
by AFLP primer combinations.
Primer combinations Total bands Polymorphic bands Polymorphism rate (%)
EcoRI-ACC+Tru1I-CAG 159 157 98.74
EcoRI-ACC+Tru1I-CAC 95 93 97.89
EcoRI-ACC+Tru1I-CAA 84 83 98.80
Total 338 333 98.52
A presence (1) or absence (0) binary data matrix containing 333 polymorphic AFLP
fragments was used to generate the genetic similarity estimates. The Nei-genetical
similarity, between 0.87 and 0.95, shows remarkable genetic variation among the
studied Poa populations. At the same time, the species of the P. pratensis group are
close to each other, only P. compressa shows some separation. Inside the group, the
similarity is the biggest between P. pratensis and P. humilis, and the smallest between
P. pratenis and P. angustifolia.
UPGMA clustering analysis was carried out in order to demonstrate graphically the
genetic similarities among the Poa genotypes (Fig. 2), to present a dendrogram of 338
AFLP fragments obtained from three primer combinations at 12 Poa populations. P.
humilis (2) is separated at a high level from other populations. P. humilis (1) and P.
humilis (3) are close to each other. P. angustifolia (2) and P. angustifolia (3) is similar,
as are P. angustifolia (1) and P. angustifolia (4). But the populations of different species
are not separated from each other as would be expected. The two populations of P.
pratensis are in different clusters.
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