Mealybugs, members of the Pseudococcidae family, are scale insects that typically form groups in plant regions. They feed on plant sap and release surplus sugars in the form of honeydew, promoting the growth of sooty mold. Additionally, they can transmit different plant diseases.
Distribution & Host Range
Mealybugs have the ability to infest plants both indoors and outdoors.
They can be found in various locations worldwide, although they are predominantly native to warmer regions.
These insect pests have a diverse host range, affecting a wide array of cultivated plants, including fruit trees, vegetables, ornamental plants, and more. This includes both broadleaved plants and grasses.
Identification of Mealybugs
In general, mealybugs are small insects with soft bodies that feed by sucking sap from plants. They have a distinctive cottony appearance. Adult mealybugs tend to form colonies on leaves, stems, and roots, making them challenging to eliminate due to the whitish masses covering their bodies.
However, different species of mealybugs possess varying characteristics. Here are some examples:
- Citrus mealybug (Planococcus citri): The anal filaments of this species are shorter than one-eighth the length of the body. Females of this species produce irregular egg masses that remain under their bodies.
- Solanum mealybug (Phenacoccus solani): The body of this species is covered with very short waxy filaments. It lacks long tails and stripes on its body. Solanum mealybugs do not produce egg masses or ovisacs.
- Mango Mealybug (Drosicha mangiferae): Female mango mealybugs can be identified by their flat shape and the white mealy powder that covers their bodies.
- Pineapple mealybug (Dysmicoccus brevipes): This species is primarily associated with the roots of host plants. It has a light pink to grey body color and possesses 17 pairs of wax filaments.
Mealybugs exhibit sexual dimorphism, with wingless females and smaller winged males.
These insect pests do not undergo complete metamorphosis.
Once fully developed, the female mealybug lays eggs enclosed in a white waxy egg sac. These egg sacs are typically found in clusters on the twigs, branches, or bark of the host plant, although they may also be present on the leaves and terminal ends.
The eggs are small, ranging from 0.3 to 0.4mm in length, and their development takes between 3 and 9 days.
Under normal conditions, an individual mealybug requires approximately 30 days to progress through all nymphal stages and reach maturity.
Mealybugs have the ability to withstand cold conditions in various life stages, including eggs, both on the host plant and in the soil. In warm climates, these insects remain active throughout the year and reproduce continuously.
Feeding & Damage
Mealybugs obtain nourishment by piercing and sucking plant parts. Both nymphs and adults extract sap, leading to the withering and yellowing of leaves. In some cases, premature fruit drop can occur. Severe infestations may result in defoliation and even the death of the plant.
Infested growing points exhibit stunted growth and swelling. The extent of the infestation’s impact depends on the susceptibility of the host plant species.
Mealybugs tend to form dense clusters beneath the surface of leaves, creating a thick mat accompanied by the secretion of wax.
While feeding, mealybugs produce a significant amount of honeydew, attracting ants. The presence of honeydew encourages the growth of black sooty mold on leaf surfaces, impeding photosynthesis. Mealybugs also affect the development of flowers and stems, particularly in succulents with fleshy stems.
Infested fruits can be completely covered with the white, waxy coating produced by mealybugs, leading to fruit shriveling.
Mealybugs possess the capability to survive through the winter season and endure extended periods without water or food. They can withstand cold conditions, persisting on both host plants and in the soil. The wide range of plants they can infest provides them with a survival advantage.
Infestation by mealybugs can result in a complete crop loss of up to 100% if left uncontrolled. Hence, it is crucial to take measures to eliminate these pests.
There are various methods available for managing and controlling mealybugs, which include:
In order to achieve effective control of mealybugs, it is important to select an insecticide that possesses systemic characteristics.
The following products are recommended for the control of this pest:
- EMERALD: Mix 10ml of EMERALD with 20 liters of water.
- LOYALTY: Mix 5g of LOYALTY with 20 liters of water.
- AMAZING TOP: Mix 5g of AMAZING TOP with 20 liters of water.
- LEXUS: Mix 8ml of LEXUS with 20 liters of water.
Note: It is essential to always combine the insecticide with INTEGRA at a ratio of 3ml per 20 liters of water. INTEGRA helps the sprayed products adhere to the leaves and stem, spread across the entire leaf surface, and penetrate the underside of the leaves.
To address the issue of sooty mold, apply JAMBO CLEAN at a rate of 100ml per 20 liters of water during the spraying process. JAMBO CLEAN is effective in cleansing the sooty mold.
- Thorough removal of all infested materials from the field.
- Implementing crop rotation by cultivating non-host plants in rotation with susceptible crops.
- Maintaining field sanitation by keeping the area clean and free from debris.
- Ensuring that field borders are clear of weeds and debris, as they can serve as potential shelters for mealybugs.