Share 'Can anyone suggest me about PCR condition for amplication matK gene with pair of primers trnK3914F and trnK2R in Panax genus'

I'm investigating phylogenetic in genus Panax (Araliaceae). I tried some published PCR condition for amplification matK gene with pair of specific primers trnK3914F (5’-TGG GTT GCT AAC TCA ATG G-3’) and trnK2R (5’-AAC TAG TCG GAT GGA GTA G-3’) (attached files) but I could not recognize the desired band. My problem is no observed band. I had tried gradient PCR with Tm ranged from 45 to 68 deegrees…