Pepper Whitefly Can Put Growers in a Pickle
The pepper, or solanum whitefly (Aleurotrachelus trachoides Back), feeds on a wide range of hosts, including edible and ornamental plants, palms, and weeds. It is a polyphagous pest, but prefers plants in the Solanaceae and Convolvulaceae families.
The pepper whitefly is an emerging pest of horticultural crops in the U.S. It has a wide distribution in Central and South America and in the Caribbean. In North America, A. trachoides’ presence has been confirmed in Mexico and the U.S. The insect has been in the U.S. for more than five decades as an intermittent pest of pepper, although until recently, was never considered a key pest of economic importance. However, in the past few years, records of its spread and damage have increased in Florida, and it has been found on a growing list of potential hosts.
In Florida, the pepper whitefly has been reported on more than 35 plant types, with most records from pepper, sweet potato, pigeon berry, coconut palm, and tomato.
It damages the host by feeding with its needle-like mouthparts used to suck plant sap. Production of wax and honeydew, which provide an excellent substrate for the growth of sooty mold, might also disrupt the photosynthetic process. Heavy infestations may lead to the host’s stunted growth and reduced fruit production, affecting the aesthetic and/or economic value of the host plant(s). The pepper whitefly is not a known vector of viruses.
Survival and Spread
Like other whiteflies, it develops through six life stages: egg, four nymphal instars, and adult. Adults are small and covered with a white waxy layer. Females lay tiny, oblong eggs on the undersides of leaves, which turn yellow to grayish-brown as they mature.
Early nymphal instars are flat, round to oval in shape, light to golden yellow in color, and may bear eight spherical patches on the dorsal surface. As the nymphal instars mature, they become more convex, their color turns darker, and they produce a dense, cottony wax and long, thin, waxy filaments. The puparium of this species has a distinct pattern comprised of three dorsal brown patches which, when magnified, gives the appearance of a mid-dorsal horizontal stripe on an otherwise light or nearly colorless body.
Although adults can fly or be carried by wind over small distances, the primary mode of dispersal is through movement of infested plant material. Thus, identification and effective monitoring are critical to reduce the movement and maintain populations below damaging levels.
Being a new pest of economic importance, not much information is available about effective management practices for A. trachoides. Researchers at the University of Florida, USDA-ARS, and FDACS are evaluating potential commercial and naturally occurring whitefly biocontrol agents, such as Encarsia formosa – a parasitoid wasp.
As with other whiteflies, soaps and horticultural oils can be used to suppress early infestations, and effective control can be achieved using application of systemic insecticides. Consult UF/IFAS recommendations of currently labeled insecticides for pepper whitefly control in Florida.