This study was carried out to determine the genetic diversity degree and genetic
relationships among seventeen genotypes involving 16 commercial cultivars and one
accession of Yemeni coffee (Coffea arabica L.) germplasm collected from different
Governorates in Yemen, and analysis of the DNA fingerprinting data for creating
molecular IDs for conservation and protection of these genotypes. These goals were done
using 15 previously described SSR primer pairs, in addition, evaluating of the efficiency
and performance of these loci to achieve these objectives. The SSR loci were very highly
polymorphic with an average of 100% polymorphism, the scored alleles were high and
ranged from 4 to 25 with a mean value of 10.7 per locus. Heterozygosity values per locus
and per genotype were low with an average of 0.21., the (PIC) values or gene diversity
differed from 0.57 to 0.98. Also, the discriminating power for all loci was high with a
mean value of 0.81; the most informative primer pairs was gSSRCa 021 with DP value of
0.94. However, the probability of matching fingerprints was low with an average value of
0.19. In this study, it was impossible to obtain identical DNA fingerprints for any of
genotype pairs at all loci, even the genotypes with the same name but were collected from
different geographical regions. However, the 15 SSR loci could differentiate between 17
Yemeni coffee genotypes through detecting of 86 clear specific/exclusive alleles. All
Cultivars and accessions had unique alleles to that genotype alone with a mean value of
5.06. The cluster analysis grouped the 17 genotypes into three main clusters with a
genetic similarity degree ranged from 0.00 to 0.486 with an average of 0.243. The
genotypes also were classified according to fruit color and geographical regions. Results
of this study confirmed the presence of genetic diversity among Yemeni coffee genotypes
ranging between a moderate to high, indicating their importance as source of genetic
variability for the purposes of coffee improvement, especially with the suffering of
Arabica coffee from the narrowness of its genetic base |
