MANILA, Philippines - Recently, the Aglao-nema production in Thailand and Indonesia are encountering a major horticultural problem. 20 to 25 percent of the productions are wilting even if sufficient water is applied. Plants that have been growing nicely for several months suddenly wilts and lower leaves turn yellow. Cuttings are also affected. Cuttings simply wilt and more often than not rot off instead of forming roots.
Upon closer examination, the cut ends of the stems are always brown, soft and rotting. Fungicide applications were ineffective. Brown lesions may also appear on the stem just below the media line.
Common denominator in all areas with Aglaonema Wilt is the presence of soil as part of the media mix. Examination of the brown rotting portion reveals a lot of nematodes visible under the low power objectives of microscope.
Solution to the problem
Healthy-looking plants infected with nematodes without wilting symptoms and yellow lower leaves may be treated with systemic organo-phosphate or other anti-cholinesterases. The soil mixes should be drenched with the pesticide. Carbofuran may also be applied on the growing media.
Plants exhibiting wilting and yellow lower leaves should be discarded and burnt.
To prevent recurrence of the infestation, all soil mixes used in production should be steamed at 85 degrees for 35 minutes.