The major pests of pineapple

Important to know 

• Mealybugs and scales are sap-sucking pests. They manifest as fluffy, wax-like material building up near the fuzzy looking insects, while scales normally hide under waxy or cottony covers. 

• Mealybugs are the most serious pests of pineapples, also transmitting the pineapple wilt disease.

Measures before planting 

• Remove alternate hosts such as hibiscus, custard apple, guava in and around the pineapple crop field. 

• Avoid using 5 to 6 years old suckers for planting as they are likely to contain some mealybugs or scales. 

• The mealybug infested fields must be prepared by removing all the plant residues and burning them. 

• Remove weeds present in the field as they support an increase in mealybug population by giving them alternate food sources. 

• Use clean sterilised equipment when undertaking planting and intercultural operations in an uninfested field. 

Measures after planting 

• Good soil fertility and water conservation practices promote strong plants that are less susceptible to mealybug/scale attack. 

• Timely weeding reduces competition with the growing pineapple plants. 

Measures in case of infestation 

• All diseased or infected plants should be removed from the field and destroyed. 

Root nematodes 

Important to know 

• Various nematodes are attracted to pineapples, but root-knot nematodes (Meloidogyne javanica) and root lesion nematoes (Pratylenchus brachyurus) affect the roots and cause premature death. 

Measures before planting 

• Controlling nematodes is difficult, so it’s recommended to use clean planting materials and clean fields. 

• A three-year crop rotation with grasses is further recommended for pineapples. Alternatively, maintain a weed-free and host-free fallow period of at least 6 months for significant decline in nematode population. 

• Thorough land preparation will reduce nematode population – it will allow the soil to dry out and accelerates the breakdown of plant material harbouring nematodes. 

Measures after planting 

• Good soil fertility management and watering practices to maintain strong healthy plants. 

• Timely weeding reduces competition with the pineapple plants. 

Measures in case of infestation 

• All diseased or infected plants should be removed from the plantation and destroyed. 

Phytophthora heart (top) rot and Phytophthora root rot 

Important to know 

• These two common fungal diseases can be controlled the same way, though they are caused by different pathogens. 

• The symptoms of root rot are similar to those caused by nematodes. A plant that looks like it needs to be watered, with drooping leaves and general signs of distress is likely to be infected. Leaves change in colour from a healthy green through various shades of red and yellow. Leaf tips and margins eventually become necrotic, the root system is dead, and plants can easily be pulled from the ground. 

• Premature ripening of fruits from infected plants. 

• Top rot may show similar signs, but also shows dead leaves around the center of the plant. 

• Both are caused by overwatering, poorly drained soils or too much rainfall. 

Measures before planting 

• A well-drained seed bed is required. 

• Avoid excessively deep planting. 

• Prevent soil entering the heart during planting. 

• Plant on raised beds of at least 20 cm height. 

Measures after planting 

• Maintain proper drainage for minimising the risk of Phytophthora infection. 

Measures in case of infestation 

• All diseased or infected plants should be removed from the plantation and destroyed.