Whitefly
Class: Insects
Common Name
Whitefly, cotton whitefly, sweet potato whitefly, tobacco whitefly, cassava whitefly, and silver leaf whitefly
Scientific name
Bemisia tabaci
Potential Hosts
Tomato, pepper, squash, melons, cucumber (and other cucurbitaceae members), broccoli, cauliflower, cabbage (and other brassica members), cotton, carrots, potato, and fresh herbs such as basil and mint
Who am I?
Whitefly is a multi-host with considerable differences that exist in appearance between adult and nymph stages. Females can lay dozens of eggs, usually on the underside of leaves. Nymphs feed by stabbing into the plant with their mouth-parts, sucking up sap from the phloem, and excreting honeydew (a sugar-rich substrate that promotes the growth of sooty mold.) The adults are white and capable of flying, hence the name.
Damage to hosts is caused directly from feeding and indirectly from honeydew. However, their ability to spread viruses have the greatest economic impact. Whitefly vector plant viruses like Begomoviruses, which is a group of plant viruses such as TYLCV in tomatoes and CYSDV in cucurbits. Whiteflies transmit Begomoviruses to host plants.
Control measures
Cultural
Growing inside structures: The most effective way to protect your crop from whiteflies is simply (but costly) growing it inside a greenhouse or a dense (50 Mesh) net structure.
Synthetic soil ground covers and floating row covers can help in reducing whiteflies from reaching host plants, hence resulting in a lower incidence of transmitted viruses.
Sanitation: Try keeping your crop’s close surroundings and environmental conditions as neat by removing weeds and any potentially close by plants that are non-cultivated or protected, which can attract whiteflies.
Traps: Use sticky yellow traps that lure and capture part of adult population; they aid in monitoring changes in the overall population.
Conventional (chemical)
The following are insecticides used in one or more parts of the world: cypermethrin, deltamethrin, bifenthrin, diafenthiuron, thiamethoxam, imidacloprid, acetamiprid, spiromefisen, buprofezin, cyantraniliprole, spirotetramat, and synthetic terpenes extract of chenopodium.
Organic
Azadirachtin, Fatty acid potassium SAL, Beauveria bassiana strain GHA, neem oil, and other plant oils
Biological
Amblyseius swirskii is a commercially available predatory mite that is capable of significantly controlling whitefly population.
Caution and careful notice should be taken when using any plant protection products (insecticides, fungicides, and herbicides). It is the grower’s sole responsibility to keep track of the legal uses and permissions with respect to the laws in their country and destination markets. Always read the instructions written on labels, and in a case of contradiction, work in accordance to the product label. Keep in mind that information written on the label usually applies to local markets. Pest control products intended for organic farming are generally considered to be less effective in comparison to conventional products. When dealing with organic, biologic, and to some extent a small number of conventional chemical products, a complete eradication of a pest or disease will often require several iterations of a specific treatment or combination of treatments.