This blog will outline the impact of major pests in citrus production and the most effective methods to identify and control them.

Citrus is one of the world’s most important economic crops and the most extensively planted fruit tree. There have been reports of over 250 pest and mite species infesting various citrus varieties in India.

The major pests that seriously harm the citrus crop include the citrus psylla, whitefly, blackfly, leaf miner, and citrus butterfly. Most insect pests appear during the new flush stage and destroy the new growth, impeding plant development. The following are significant insect pests of citrus in India and how they are managed:

Major pests of citrus are

• Citrus Psyllid
• Citrus Aphid
• Citrus Mealybug 
• Fruit-sucking moth
• Citrus Whitefly

Pests	Symptoms	Control
Citrus Psyllid	Leaves twist and curl. Shortened shoots, with broom effect. Secretion of honeydew inside the nymphs	Maintain sanitation. Preserve parasitoids like Diaphorencyrtus aligarhensis and Tamarixia radiata.
Citrus Aphid	Infected leaves develop a cup-like shape. Leaves wrinkles.	Make use of yellow sticky traps. Protect and increase the number of predators.
Citrus Mealybug	Defoliation, fruit discolouration, fruit splitting, and fruit drop. Early leaf fall and twig dieback	Gather and remove the harmed stems, twigs, and leaves.  Apply a sticky barrier to the trunk (5 cm long).
Fruit-sucking moth	Early fruit decay.	Destruction of larval hosts (any alternative host) near orchards. Gathering and destroying fruits that have fallen.
Citrus Whitefly	Secretion of large quantities of honeydew	Avoid close planting and waterlogging.

Citrus psyllid

The citrus psyllid is one of the invasive pests in the cultivation of citrus. Southern Asia is home to a large population of the Asian citrus psyllid. It is a significant citrus pest in many nations because it is a dangerous disease vector. Several citrus industries in Asia and Africa have been destroyed as a result of this disease.

Symptoms of Citrus Psyllid

• In addition to harming the tree’s leaves and stems, this can also spread bacteria.
• Psyllids have piercing-sucking mouthparts.
• Psyllid adults and nymphs that feed cause newly produced leaves to twist and curl, much like the green aphid.
• Psyllid feeding also shortens shoots, giving them a witches’ broom effect.
• The developing flush will fail to develop or abort if excessive feeding occurs at the flush’s beginning.
• In addition to causing direct feeding damage, honeydew inside the nymphs’ white waxy secretions encourages the establishment of sooty mould, which can decrease the amount of leaf area that is effective for photosynthesis.

Management of Citrus Psyllid

• Maintain appropriate field sanitation by trimming, collecting, and burning twigs from the previous year.
• Keep curry leaf plants away from the citrus orchard as it serves as an alternate host for the pest, inviting citrus psyllid to your farm.
• Avoid using nitrogenous fertilisers excessively.
• Gather and eliminate the infected plant components.
• Preserve parasitoids like Diaphorencyrtus aligarhensis and Tamarixia radiata.
• Encourage predators like Syrphids, Coccinellids, and Chrysoperla zastrowi sillemi.

Citrus Aphid

Aphids are the major pest affecting citrus production worldwide. Farmers should recognise aphid infestation at the right time in order to get better quality fruits.

Symptoms of Citrus Aphid

• Citrus aphid consumes delicate flowers and greenery.
• It spreads the disease caused by the Citrus Tristeza virus.
• Adults and nymphs ingest the sap from leaves, which causes withering and blossom wilting.
• Infected leaves develop a cup-like shape and are wrinkled.
• The plants’ growth is hampered.

Management of Citrus Aphid

• Make use of yellow sticky traps.

• Protect and increase the number of predators, such as lacewing birds, earwigs, some ground and rove beetles, and spiders.

Schedule of foliar insecticide sprays

Sprays	Percentage	Quantity
Dimethoate	30% EC	594-792 ml per acre in 600-800 l of water.
Chlorpyrifos	20% EC	600–800 ml per acre in 600–800 l of water
Monocrotophos	36% SL	600–800 ml in 200–800 l of water per acre.

Citrus Mealybugs

Citrus mealybugs are one of the dangerous pests affecting citrus production globally. This pest has caused significant losses in India’s northeastern and peninsular regions.

Symptoms of Citrus Mealybugs

• The occasional citrus pest known as the citrus mealybug is most common in older, heavily-planted, well-shaded citrus plantations.
• They will consume the fruit, leaves, roots, and bark as food. The citrus mealybug injects toxic saliva as it extracts plant sap, causing defoliation, fruit discolouration, fruit splitting, and fruit drop.
• Mealybugs typically congregate in huge groups, and as they feed, they cause early leaf fall and twig dieback. They release honeydew, similar to psyllids, which draw black sooty mould.

Management of Citrus Mealybugs

• Trim any damaged shoots over the winter.
• Plants that attract natural predators like wasps should be grown.
• Wasps are attracted to plants like bachelor buttons, cornflowers (Centaure acyanus), and coriander.
• Introduce predators like Cryptolaemus montrouzieri, an Australian ladybird beetle with 10 bugs per tree.
• Gather and remove the harmed stems, twigs, and leaves.
• Apply a sticky barrier to the trunk (5 cm long).

Fruit-sucking moth 

Fruit-sucking moths are the destructive pest of citrus. They are known for sucking the juice out of the fruits resulting in deterioration in fruit quality.

Symptoms of Fruit-sucking moth

• It is a significant pest of mature mandarin fruits.
• The adults pierce the ripening fruits.
• Such fruits decay early due to bacterial and fungal diseases introduced through punctures, which results in significant fruit loss.

Management of Fruit-sucking moth

• Destruction of larval hosts (any alternative host) near orchards.
• Gathering and destroying fruits that have fallen.
• Before one month of fruit ripening, collect and destroy moths at night using a battery-powered or flame torch and place one fluorescent light trap per acre.

White fly

Among the devastating pest of citrus, whiteflies are one of the important pests that cause severe damage to citrus production. It is essential to take preventative measures quickly to control pest infestation.

Symptoms of White fly

• Both nymphs and adults consume a lot of nectar. 
• Sooty mould fungus, which develops on fruit and foliage in large quantities of honeydew secreted by the whitefly, causes additional damage. 
• Heavy infestation causes plants to weaken and yield small amounts of tasteless fruit.

Management of White fly

• Close planting, water logging, and other stressful situations should be avoided for successful fly management.
• Spraying with malathion, phosphamidon, and dimethoate (0.03%) in April through May and once again in September through October is an effective preventive measure against citrus whitefly.

How can Fasal Assist?

• Citrus pests can destroy the whole cultivation in a matter of days. With Fasal technology, the effects of citrus pests can be reduced and farmers can easily protect their fields.
• Fasal technology is an IoT-based system that keeps track of all the factors that play a role in pest infestation. 
• Sensors installed in the system reduce the danger of infection from citrus pests while also monitoring rainfall, humidity, temperature, canopy level forecasts, and an ultra hyper-local macro-climatic forecast to alert farmers when circumstances are right for pest invasion.
• With the help of Fasal technology, farmers can keep an eye on their farms. The Fasal system alerts farmers about pests and diseases and recommends the right amount of pesticide needed for a crop, therefore, helping to lower the cost of pesticides for farmers.