The Application of Ooubled Haploid Plants to Population ... - MSpace

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distinguish behnreen their presence or absence. These primers and their sequences
are shown in Table 5.1,
A total of 98 RAPD produds were visualired, including 57 polyrnorphic and 41
monornorphic bands. The number of bands produced per primer ranged from 4 to 15.
Polymorphism was expeded between the DSC-3 and Reward donor populations.
Primers used in this test differed in their ability to detect genetic variation in each of the
collection of DH Iines (Table 5.2). Bands expressed when DSC-3 was amplified with
primer 318 (UBC) were monornorphic for the OH lines. AH other prirners resulted in
polymorphic expression of bands in the DH lines from both donor populations (Fig 5.1).
Application of RAPD analysis
Genetic variation and therefore the RAPD pattern expressed in a population is
affected by the number of individual plants in the population and the number of
generations of inbreeding ocairring (Falconer and Mackay. 1996). RAPO analysis
demonstrated that as the number of individual DH lines incfuded to create each
composite population increased, there was more genetic variability expressed in Co
(Table 5.5). After one and two generations of intecpollination, al1 C, and C, populations
expressed less polymorphism than the corresponding DH Iines (Co) used in their
production. This is expeded because of the restided nurnber of lines used to produce
C, and C,. lnterpollination results in eventual fixation or loss of alleles. The level of
polymorphism that was reached in C, and C, was similar for al1 population sires. The
lowest level of polymorphism was expressed when only 4 DH lines contributed to C,