Pineapple top and root rot

Top rot initially manifests in a colour change of heart leaves from green to yellow or light-brown with a red tinge. The leaf edges curve back and leaves are easily pulled out from the plant. Internally, the stem and leaf bases become soft, rotten and have an unpleasant smell. The growing point of the stem has a cheese-like appearance. Root rot causes similar symptoms like top rot. However, the outer leaves become limp and dieback from the tips. By this stage, the root system has rotten and plants can be easily pulled from the ground. Rot rot often extends through the stem to cause top rot. Fruits from diseased plants are normally small and are not marketable. Both P. cinnamomi and P. nicotianae var. parasitica are soil inhabitants and require water for spore production and infection. These fungi prefer wet soil conditions.