Cvs Red Spanish, Smooth Cayenne and Sugar Loaf pineapple plants in nematode-infested plots which were fumigated before planting then received after-planting nematicidal treatments, grew faster, produced better root systems, showed less symptoms of nutrient deficiency and produced significantly higher yields than plants in plots which received the first nematicidal treatment 4, 8 or 12 months after planting than at 4-monthly intervals. There was little difference in the performance of the plants receiving the various after-planting treatments only or no treatment. For cv. Smooth Cayenne, plots receiving the before and after-planting treatments produced significantly more slips and suckers than the other plots. For all varieties, the benefits of the pre-planting treatment carried over to the ratoon crop. It appears that once pineapple plants have been damaged by nematodes, they derive little benefit from nematicidal treatments.
