• Mealybugs may be a minor problem indoors
• Aphids may be a minor problem outdoors
• Older leaves turning yellow is first a sign of water stress and second light stress
• Light stress plants will have a very straight appearance as they try reaching for a light source
• Mites and Disease should not be an issue indoors

     Mealybugs can be removed with a systemic insecticide drench and hand cleaning.  If pesticides are not an option, try horticultural oil directly sprayed onto the insects.  A second and third treatment, if using oils,  will be necessary.  Space out the sprays at 3 week intervals to break up the mealybug life cycle.

    This plant does not have significant pest problems in the nursery.

Other Links:

Progression of Low Light Stress on Dieffenbachia 'Camouflage'