Development of chloroplast simple sequence repeats (cpSSRs) for the intraspecific study of Gracilaria tenuistipitata (Gracilariales, Rhodophyta) from different populations.
BACKGROUND
Gracilaria tenuistipitata is an agarophyte with substantial economic potential because of its high growth rate and tolerance to a wide range of environment factors. This red seaweed is intensively cultured in China for the production of agar and fodder for abalone. Microsatellite markers were developed from the chloroplast genome of G. tenuistipitata var. liui to differentiate G. tenuistipitata obtained from six different localities: four from Peninsular Malaysia, one from Thailand and one from Vietnam. Eighty G. tenuistipitata specimens were analyzed using eight simple sequence repeat (SSR) primer-pairs that we developed for polymerase chain reaction (PCR) amplification.


RESULTS
Five mononucleotide primer-pairs and one trinucleotide primer-pair exhibited monomorphic alleles, whereas the other two primer-pairs separated the G. tenuistipitata specimens into two main clades. G. tenuistipitata from Thailand and Vietnam were grouped into one clade, and the populations from Batu Laut, Middle Banks and Kuah (Malaysia) were grouped into another clade. The combined dataset of these two primer-pairs separated G. tenuistipitata obtained from Kelantan, Malaysia from that obtained from other localities.


CONCLUSIONS
Based on the variations in repeated nucleotides of microsatellite markers, our results suggested that the populations of G. tenuistipitata were distributed into two main geographical regions: (i) populations in the west coast of Peninsular Malaysia and (ii) populations facing the South China Sea. The correct identification of G. tenuistipitata strains with traits of high economic potential will be advantageous for the mass cultivation of seaweeds.
Sze-Looi
SL
Song
Institute of Biological Sciences, University of Malaya, 50603 Kuala Lumpur, Malaysia. phaikeem@um.edu.my.
Phaik-Eem
PE
Lim
Siew-Moi
SM
Phang
Weng-Wah
WW
Lee
Dang Diem
DD
Hong
Anchana
A
Prathep
D000483:Alleles; D017931:DNA Primers; D018742:DNA, Chloroplast / Q000235:genetics*; D044724:Gracilaria / Q000145:classification / Q000235:genetics* / Q000302:isolation & purification; D008296:Malaysia; D018895:Microsatellite Repeats; D010802:Phylogeny; D019105:Random Amplified Polymorphic DNA Technique; D013045:Species Specificity; D013785:Thailand; D014744:Vietnam
D017931:DNA Primers; D018742:DNA, Chloroplast