Introduction. In Malaysia, Limau Madu (Citrus
reticulata Blanco; Citrus suhuiensis Hort.
ex Tanaka) is commercially cultivated for local consumption. It
is a loose-peel mandarin with fruits that are spherical in shape
with shiny green or greenish yellow peel. In Malaysia, Limau Madu
is vegetatively propagated, thus it is presumed to exhibit minimal
variability. In our study, the genetic variability and genetic relatedness
among cultivated samples collected from different states in Malaysia
were assessed using Simple Sequence Repeat (SSR) primers. Materials
and methods. Thirty pairs of SSR primers derived from Citrus
unshiu were screened and 22 SSR primer pairs were utilized
to assess genetic variability and relatedness among 118 cultivated
samples. Results and discussion. The percentage of SSR transferability
from C. unshiu to C. reticulata (Limau
Madu) was 73.33%, which indicated that the primer sequences flanking
simple sequence repeats were conserved among these Citrus species.
Most SSR loci revealed a large excess of heterozygotes. In our study,
low allelic diversity was shown, with an average of 5.227 alleles
per locus. Polymorphic information content (PIC) ranged from 0.048
to 0.674. Based on UPGMA clustering analysis, four groups were identified
from these citrus genotypes with a mean genetic distance of 0.170. Low
genetic variability within species was probably due to vegetative
propagation or inability to detect differences among samples using
these primers.