Attacks paphiopedilums; bacterial brown rot starts as small roundish water-soaked yellow spots often in the middle of the leaf; changes to dark chestnut; may appear greasy; reaches growing point of plant and changes it to dark shrivelled mass; isolate plants; disinfect bench with Clorox 10%; destroy all leaves; spray with Physan 20, 1.5 tpg. or drench in Natriphene 1:2,000 tpg.). B40; BU49