Cluster Analysis of Dendrobium by RAPD and Design of Specific Primer for Dendrobium candidum Species specific molecular diagnosis of burrowing nematode (Radopholus similis) Authentication of TCM Carapax Trionycis by allele-specific diagnostic polymeras chain reaction Screening and Analysis of Mutiple Copy of Oleate Desaturase Gene (fad2) in Brassica napus Molecular detection of Pseudomonas syringae pv. actinidiae on bacterial canker of kiwifruit