Bugs, late-blooming trees may be the cause of citrus problems | Entertainment / Lifestyle

Citrus is the most popular fruit in Louisiana. Satsuma and other types of citrus are plentiful and delicious this time of year.

However, several biotic and abiotic stresses can affect citrus yields, and it can be frustrating for home gardeners when they can’t enjoy the harvest.

One problem faced by citrus growers is dry rot inside the fruit. Ripe fruit affected by this condition may look healthy on the outside—but peeling the fruit reveals dry, discolored flesh. This internal dry rot is caused by a yeast called Nematospora coryli spread by the western leaf-footed beetle (Leptoglossus zonatus).

Leaf-footed insects are widespread and are pests of many crops, including fruits, vegetables, grains, nuts, and ornamentals. It is a major pest of citrus, mainly attacking tangerines. It feeds by inserting piercing-sucking mouthparts into fruit. Feeding on ripe fruit can cause premature fading and fruit drop. Injury usually occurs in autumn when the fruit is ripe. While feeding, leaf-footed insects spread the yeast responsible for internal dry rot.

Adults can fly great distances and move to satsuma from other crops during fruit ripening in the fall. Leaffoot insects will congregate in swarms on a single tree, while neighboring trees are completely free of bugs.

Adults are dark brown in color with flattened, leaf-shaped hind legs. Nymphs, or immature bugs, look quite different from adult bugs. Their body color ranges from orange to reddish brown with black legs.

Leaffoot is mainly managed through the use of insecticides, but other insects and entomopathogenic fungi can also be used for biological control. Homeowners can spray horticultural oil or Malathion 57EC to manage leaffoot in backyard trees. Remember – do not spray malathion on blooming plants and make sure to wait at least 7 days after spraying before harvesting fruit.

Another problem that citrus growers may have is puffy fruit. Fluffy, misshapen fruit is mostly a problem with young, vigorously growing citrus trees. As the tree gets older, the appearance of swollen fruit decreases. Fluffy fruit on older trees is due to late blooming fruit during warm weather.

In contrast to the round, smooth, healthy fruit, the fluffy satsuma has a thick, wrinkled rind and is pear-shaped. After peeling, satsuma looks dry without any juice.

There’s almost nothing you can do to prevent puffy fruit. But good growing conditions, proper fertility, and pest and disease control always help keep citrus trees healthy.