Aleurotrachelus atratus better known as the palm-infesting whitefly is an invasive species that affects coconut palms. Originally, this species was only prevalent in Brazil and was known to feed on coconuts native to this country. Now, the species has migrated to the tropics and subtropics and is invasive in many other countries. Aleurotrachelus is one of the largest genus, containing 74 species.
Description
Aleurotrachelus atratus are small insects whose puparia have wax filaments that cover the bug in its entirety. A. Atratus are generally dark yellow with all four larval stages being black. Adult whiteflies are very small bugs with white wings. Females lay eggs on the underside directly onto plant leaves, and eventually, eggs become crawlers after 6 days. These nymphs remain on the same leaf for the rest of their development until they emerge as winged adults. This cycle takes about 3 weeks in favorable conditions, however, the whiteflies are able to survive in freezing temperatures. Identification of the species is best through mounted slides as most species of the whiteflies have very similar characteristics. The slides confirmed an elongated oval puparium with an entire dark cuticle, marginal teeth separated, rounded apices/ converging suntruncare,
Range and habitat
Originally Aleurotrachelus atratus was first reported in South America but new reports have been made in North America, Central America, the Caribbean, Africa and in the lower parts of Asia. They are able to travel short distances by flying most reports are due to infected plants being brought into areas where there are no natural predators for the whitefly. Aleurotrachelus atratus prefer tropical habitats where coconut palms are cultivated. Whiteflies also migrate towards agricultural land, managed forests, plantations and orchards.
Life cycle
The life cycle for Aleurotrachelus atratus lays anywhere between 50 and 400 eggs in its lifetime. From egg to crawler then through second, third, and fourth instar nymph, and finally, an adult Aleurotrachelus atratus the full life cycle takes around 48 days or 2 months. Most of the days are spread out between the three instar while from egg to crawler takes about 4-12 days for the larvae to hatch.
Agricultural threat
India is the largest coconut producing country in the world with contributions of global production totaling 31%. Coconut palms are a major food source and provide livelihood opportunities to more than 12 million people in the country. There are 464 species of whiteflies in India but A. atratus poses a higher threat compared to other species.
Host plants
Primarily host plants for A. atratus are Cocos nucifera (coconut palm) other host plants that may be infected by Aleurotrachelus atratus includes Washingtonia spp. (fan palms), Phoenix dactylifera (date palm), Veitchia merrillii (Christmas palm), and Elaeis guineensis (African oil palm). Most of the plants from the Arecaceae family are infected by Aleurotrachelus atratus.
Damage by feeding
Coconut palm flies feed on the underside of palm leaves. The removal of sap reduces plant vigour, causing chlorosis. This leads to premature leaf drop which ultimately reduces yields. In addition to weather damage, large infestations of whiteflies cause death of the palms.
Invasive impacts
Some invasive impacts that Aleurotrachelus atratus cause are economic strains that lead to social impacts. Some economic strains would cause targeted crops to produce lower yields and negatively change normal cultural practices. Social impacts would be parallel with economic impacts as the livelihood of the farmers would decrease and limit social opportunities. Environmental impacts cause changes in cultural practices and may cause official or private programs to take action in controlling the pest.