[An analysis of genetic diversity of different ecotypes of reed (Phragmites communis Trin.) by molecular marker techniques].

ISSR (inter-simple sequence repeat) and RAPD (random-amplified polymorphic DNA) markers were used to detect genetic diversity of 4 different ecotypes of reed (Phragmites communis Trin.) growing in Hexi Corridor, Gansu province. Nine effective primers were screened from 30 ISSR arbitrary primers, and a total of 99 DNA bands were amplified, among which 51 (51.5%) were polymorphic. Thirteen effective primers were screened from 45 RAPD 10-oligonucleotide arbitrary primers, and a total of 195 DNA bands were amplified, among which 87 (44.6%) were polymorphic. Genetic identity based on ISSR and RAPD data showed a positive correlation (r=0.845, P<0.05). Based on unweighted pair-group method with arithmetic averages (UPGMA) cluster analysis on DNA bands amplified, together with the correlation analysis between genetic distance and soil water contents and soluble salt contents as well, the present results suggest that the genetic diversity occurs among the four ecotypes of reed in adaptation to long term natural drought and salinity, showing an obvious evolutional tendency from swamp reed via salt meadow reed to dune reed.