Instructions for preventing mealybugs in pepper

Striped mealybugs damage young buds, undersides of leaves, flower buds and pepper fruit buds, often breaking out during the hot and humid dry season. Instructions on identifying and controlling ants, cleaning the orchard and spraying at the right time.

Summary: Striped mealybugs are a group of mealybugs that damage the aboveground part of pepper, easily seen on the underside of leaves, buds, flower spikes and fruit stalks. Aphids suck sap, causing yellow leaves, falling stems, and flat fruits; Aphids' honeydew also attracts ants and sooty mold into the orchard. This article guides how to detect early and prevent IPM, not spraying widely.

Applies to: Pepper orchards with basic construction and business in the Central Highlands and Southeast.
Duration: Monitoring all year round, peak dry season and bud, flower, and fruit stages.
Difficulty level: Medium.
Estimated additional costs: 1.5-3 million VND per hectare per year for inspection, cleaning, ant control and local spraying.

Striped mealybugs are different from regular mealybugs

Striped mealybugs are larger in size than many other mealybugs, have a long oval body, and are covered with white wax powder. There are waxy streaks on the back that are thicker than the sides so it looks like "stripes". At the end of the abdomen there is a pair of long and large wax tassels.

Features to note:

Female bed bugs lay many eggs, a nest can have several hundred eggs.
Baby bedbugs hatch quickly and spread to young parts.
Aphids can move with ants, rainwater, tools and branches touching each other.
The white wax layer makes it difficult for bedbugs to come into direct contact with the drug.

Therefore, treating bedbugs must be done early when the nest is still small.

Location of damage on pepper

Striped mealybugs often appear in:

The underside of young leaves and banh chung leaves.
Buds.
Flowers.
Grow young fruit.
Axis of branches, trunk joints, dense canopy areas.

During the dry season, aphids often gather in fruit clusters and young buds. If you don't check the underside of the leaves, it's easy to miss.

Recognizing symptoms

There are white wax patches, looking like small cotton on leaves/branches/stems.
Young leaves are yellow, slightly curved, and grow slowly.
The flower or fruit stem has fallen off.
Young fruit is stunted and flat.
There are a lot of ants running on the pepper wire.
Leaves and branches are covered black with sooty fungus due to the sweet nectar of aphids.

When you see sooty mold, aphids have been present for a long time. At this time, you need to find aphid nests, not just wash the black layer on the leaves.

Processing threshold

Check 30 random wires/branches at 5-10 pillars:

Bedbug level	Action
Less than 5 percent of branches have aphids	Monitor and clean small drives
5-10 percent	Spray locally for bed bugs, control ants
Over 10 percent	Process the whole batch, repeat the test after 7-10 days

There is no need to spray the whole orchard when there are only a few aphid nests. Spraying too widely can easily kill natural enemies and cause aphids to come back stronger.

Preventive measures

Clean the canopy and root

Cut off branches close to the ground, thick branches, and unnecessary eel wires.
Prune ineffective branches after harvest.
Collect branches heavily affected by aphids and destroy them.
Do not leave weeds and bushes close to the target posts.

A well-ventilated orchard helps reduce shelter for bedbugs and ants.

Ant control

Ants are the "transportation vehicles" of bed bugs:

Ants eat honey secreted by aphids.
Ants protect aphids from ladybugs and parasitic wasps.
Ants carry young aphids to other plants.

How to do:

Whitewash the base of the pillar.
Place ant-proof glue/oil ring if the post is suitable.
Find and treat ant nests at the edge of the orchard.
Cut branches that touch the ground to cut off the ants' climbing path.

If ants are not treated, aphids usually recur after 2-4 weeks.

Protect natural enemies

Important natural enemies:

Ladybugs eat aphids.
Parasite wasps.
Flies eat aphids.
Spider catching prey.

Limit broad-spectrum spraying when aphid density is low. When spraying is necessary, prioritize local spraying and choose crop-protection products that are less harmful to natural enemies.

Spray when necessary

Spray time

Most effective when:

The bed bug is young.
The bedbug nest is not too thickly covered with wax.
The weather is dry, no rain for 6-8 hours after spraying.
Spray in the cool afternoon.

Spraying when the aphids have covered each thick patch will reduce the effectiveness, you need to cut off the heavy branches first.

Active ingredients can be used

Depending on the label of the drug allowed to be used on pepper:

Abamectin.
Abamectin + Azadirachtin.
Matrine.
Rotenone.
Buprofezin.
Spirotetramat.
Alpha-cypermethrin or suitable active ingredient at high concentrations.

You should rotate active ingredients, do not use the same type many times in a row.

Spray technique

Spray thoroughly on the underside of leaves, buds, flower stems, and fruit stems.
Add additional adhesive according to the label if necessary.
Spray locally on the aphid nest first, only spray the entire lot when the density is high.
Repeat after 7-10 days if there are still young aphids.

With mealybugs, spraying technique is as important as the active ingredient. treatments that cannot reach bedbugs are less effective.

Treat heavy bed bugs

If a branch or a piece of wire is covered with aphids:

Step 1: cut off heavy branches/vines, remove them from the orchard and destroy them.

Step 2: wash the remaining part with moderate pressure water if the plant is healthy.

Step 3: selectively spray the area with aphids and neighboring plants.

Step 4: control ants on the same day.

Step 5: check after 7-10 days.

You should not keep branches covered with aphids because they can spread very quickly.

Seasonal Tracking

Dry season

Check every 7-10 days.
Pay attention to fruit buds, buds and undersides of leaves.
Early ant control.

The beginning of the rainy season

Young bed bugs can be spread by rain.
Prune dense branches.
Spray locally if bed bugs remain.

After harvest

Pruning branches infected with aphids and ineffective branches.
Spray the orchard if aphids/soot fungus is severe.
Organic fertilizer helps plants recover.

Monitor periodically

[ ] Ratio of branches/vines with aphids.
[ ] Are there ants active on the pillar?
[ ] Is there any sooty mold on the leaves/stems?
[ ] Number of bedbug nests removed.
[ ] Active ingredients sprayed and results after 7-10 days.

If the orchard has repeated mealybug outbreaks many times, it is necessary to consider whether the canopy is too dense, high nitrogen fertilization or poor ant control.

Common mistakes

Only spray where white aphids are visible: miss young aphids on the underside of leaves and in the interstices.

Do not treat ants: aphids return quickly.

Spray when the aphids are covered in thick wax: the drug is difficult to reach, low effectiveness.

Continuous use of an active ingredient: bed bugs easily lose drug sensitivity.

Spray the entire orchard when the aphid nest is still small: kill natural enemies, ecological imbalance.

Take notes

Date of discovery of bedbug nest.
Location in the orchard.
Harmful parts: buds, leaves, flower buds, fruit buds.
Are there ants/soot fungus?
Treatment measures and effectiveness after 7-10 days.

Clearly recording by batch helps to know which areas are prone to bedbugs so you can check earlier next season.

References

*Pepper pests and prevention measures* — Vietnam Academy of Agricultural Sciences, National Agricultural Extension Center.
*Guidelines for preventing striped mealybugs* — Hainong technical document.
*Managing mealybugs on pepper according to IPM* — Plant Protection Department.