Whiteflies are winged insects that look like tiny moths and are covered in white waxy powder. They are bugs related to aphids and scale insects. They have hair-like, piercing-sucking mouthparts that allow them to extract nutrients from plant tissue. Whiteflies suck on ornamental plants in Florida.
Biological Cycle of Whiteflies
- Whiteflies go through four stages of development: egg, nymph, pupa (final instar nymp), and adult
- They lay eggs on the down part of the leaves
- The eggs hatch between four to twelve days; the number of days depends on the temperature
- 6-legged nymphs or crawlers come out of these eggs and can move for many hours, in search of a feeding site
- After settling on a site, they insert their mouthparts (which are hair-like and sharp) into leaves to feed on the sap
- They go through four nymphal stages before developing wings and other adult characteristics in the final stage
- This last stage also termed the "pupal" stage, can be identified with the greatest accuracy
- The pupa will hatch into adult whitefly, which will reproduce and lay eggs for the next generation
- Depending on the whitefly species, host plant, and environmental conditions, the time it takes from egg to adult can range from 4 weeks to 6 months
Damage by Whiteflies
- Whiteflies feed on phloem in plant tissues. Such insects can cause plants to turn dry yellow or fall off
- Whiteflies emit a sugary substance called honeydew. It causes leaves to turn sticky or get covered with black soot
- Whiteflies spread viruses to vegetable crops, citrus, pomegranate, and avocado trees
Whiteflies at low levels are usually not harmful. Unless they are carrying a plant pathogen, adults will not cause significant damage. Plant losses are uncommon in the case of a large population of whitefly nymphs.
☛ Also Read: Weekly Current Affairs
Whiteflies - Management Control
The management needs to be careful in removing population plants with Whiteflies. Early stages of Whiteflies need to be kept vigilance by removing infested leaves or hosing with water sprays.
Reflective mulches and yellow sticky traps can monitor Whiteflies. Insecticides, soaps, or oils can reduce its occurrence.
Whiteflies in India
- Aleurodicus dispersus, which was the first reported whitefly in the country, is distributed throughout India (excluding Jammu & Kashmir)
- Aleurodicus rugioperculatus, the rugose spiralling whitefly, first reported in Pollachi, Tamil Nadu, in 2016, is now found all over the country
- These varieties of Whiteflies have been reported on over 320 and 40 plant species, respectively
Most whitefly species are native to Central America or the Caribbean islands. The sweet potato whitefly, also known as the Silverleaf whitefly (Bemisia tabaci), the ficus whitefly (Singhiella simplex), and the citrus whitefly are among the most economically important species found in Florida (Dialeurodes citri).
Whiteflies are not healthy for plants. Awareness about this insect must be spread, and necessary steps should be taken to combat them.
FAQs on Whiteflies
Q.1. What is the best insecticide for Whiteflies?
The best insecticide for Whiteflies is Imidacloprid.
Q.2. Is Neem oil effective against Whiteflies?
Using Neem oil stops Whiteflies from laying eggs.
Q.3. Do ladybugs eat Whiteflies?
Yes, ladybugs eat around hundreds of Whiteflies a day.
Q.4. Does Marigold repel Whiteflies?
French Marigold is an effective repellant against Whiteflies.
Q.5. What do Whiteflies' eggs look like?
Whiteflies' eggs are pale when they are just laid and brown when hatched.