Abstract: In order to utilize RAPD technology in identification of loquat cultivars and genetic analysis, the RAPD fingerprints of 16 loquat cultivars from agarose and polyacrylamide gel electrophoreses were compared, which were carried out with latest optimization of RAPD technique in choosing 11 nt primers and strict screening PCR annealing temperature. The results showed that more bands and more polymorphic bands could be detected by the polyacrylamide gel electrophoresis (PAGE) than the agarose gel electrophoresis. Two polygenetic trees derived from the fingerprint data collected from two electrophoreses were constructed, showing that the result from PAGE electrophoresis was more consistent with the regular classification of these loquat cultivars by phenotypic traits. The results of cloning and sequencing of 38 PCR amplified fragments showed that 37 fragments were RAPD amplified products generated by the corresponding primers, among which 6 sequences were segments of protein-encoding genes, suggesting RAPD could amplify both protein-encoding and non-protein-encoding gene sequences, and could reveal the genetic variability of different loquat cultivars.

Key words: loquat, RAPD, agarose gel electrophoresis, PAGE