Mealybugs (Dysmicoccus sp.) infest commercial pineapple plantings, affecting pineapple production in several ways. The rapid spread of this malady in the field is largely due to the feeding habit of bugs. Symptoms first appear on roots which cease to grow, eventually leading to collapse of tissues. Feeding of Dysmicoccus species on pineapple produces a toxic effect called mealybug stripe, expressed as green or black striped areas. The most predominant symptom is wilting of leaves, commencing from leaf tips. Reddish-yellow colour develops in the wilting areas. Finally the plants rot and develop decaying suckers. Fruits developed are undersized. Ants of several species act as carriers of mealy bugs.

Management:

For control of mealy bugs, adopt the following measures: Apply quinalphos at 0.05%. Destroy grasses and other monocot weeds, which serve as alternate hosts for the pest.

Leaf Spot

Leaf spot occurs frequently in moist and warm climate. Small water soaked areas developed on leaves, which gradually enlarge. The affected portions become pale yellow in colour and gradually dry up. This disease is caused by Phytophthora spp.

Management:

For control of leaf spot, spray with any one of the following fungicides when symptoms of the disease are noticed:

Plant Protection-Mauritius

Sun burn:

This anomaly occurs usually when the pineapple plant leans or falls over exposing one side of the fruit directly to the rays of the sun, thus resulting in long exposure of the peel, and flesh beneath it, to fairly high temperatures.

Affected fruits show a yellowish color in the area exposed to the sun. As the anomaly progresses the yellow area changes to brown and the flesh beneath it becomes more translucent. The peel may crack between the fruitlets, the flesh dries out and becomes spongy. The occurrence of sunburn during early stages of fruit development reduces the growth rate on the area exposed to the sun thus resulting in an asymmetric fruit.

During summer months protection from the scorching sun can be done by putting dried grasses, coconut or arecanut leaves.