Comparative analysis on the diversity of Auricularia auricula-judae by physiological characteristics, somatic incompatibility and TRAP fingerprinting

Phenotypic traits (physiological characteristics and somatic incompatibility) and genotypic traits (target region amplification polymorphism TRAP) were used to study the diversity of 32 main cultivars of Auricularia auricula-judae in China. Twenty seven important and stable physiological indexes were evaluated; somatic incompatibility test (SIT) reaction was described from three aspects: type, pigment, and intensity; 16 pairs of TRAP primer combinations produced 535 unambiguous and reproducible DNA fragments, of these 524 (97.9%) were polymorphic. Dendrograms were constructed by Unweighted Pair-group Method with Arithmetic Averages (UPGMA) method, and the principal coordinate analysis (PCO) of the three methods (physiological characteristics, SIT intensity and TRAP) exhibited similar clustered patterns, revealing that all the tested strains could be divided into three distinct groups, each of which was correlated with different geographical regions. Most strains originated from the same area were with a narrow genetic basis and could possibly be domesticated from the local wild-type strains, some strains were suspected to be synonymous. The grouping information obtained in the present work provides significant information for further genetic improvement of A. auricula-judae.