Multiplex Group

Stop Citrus Greening Disease Before It Destroys Your Orchard

24 August 2026

Bright, juicy, and packed with health-boosting Vitamin C, citrus fruits are a true pride of Indian farming. From Nagpur Mandarins and Punjab Kinnows to local Acid Limes, these popular fruits bring income to millions of hard-working farmers and fresh energy to our everyday diets.

However, a serious disease known as Citrus Greening—also called Huanglongbing (HLB) or Yellow Dragon Disease—is silently destroying citrus orchards across India. Caused by a phloem-inhibiting bacterium (Candidatus Liberibacter) and spread by a tiny insect called the Asian citrus psyllid, it attacks the tree's vascular system and blocks the flow of vital food and water. It has already spread across 16 major farming states, causing leaves to turn yellow, branches to dry up, and crop yields to drop by up to 40%.

The damage reaches straight inside the fruit itself. Because the tree cannot deliver nutrients to the growing fruit, natural sugars vanish while harsh acids and off-tasting bitter compounds shoot up dramatically. Instead of sweet, refreshing juice, farmers are left with small, misshapen, and bitter fruit that no one wants to buy—threatening the livelihood of entire farming families across the nation.

Spotting Citrus Greening (HLB) early is the key to protecting your orchard. Because the disease blocks the flow of food inside the tree, symptoms quickly show up on both the leaves and the developing fruit.

Visual Signs Every Farmer Should Look For:

1. Leaf Symptoms (Uneven Yellowing)

Blotchy Mottle: Random, uneven yellow-and-green patches. Unlike simple nutrient deficiency, one side of the leaf vein looks completely different from the other.
Yellow Shoots: A single branch near the canopy top turns bright yellow while surrounding branches remain green.
Corky Veins: The main central vein underneath becomes swollen, yellow, and brittle.

2. Fruit Symptoms (Small, Lopsided, Bitter)

Crooked Shape: Fruits stay small and lopsided, with a twisted central core when cut in half.
Reverse Ripening: Fruit turns yellow near the top stem while the bottom tip stays dull green.
Heavy Drop: Fruits fall off early, long before harvest.
Dark Seeds: Seeds inside appear small, shriveled, and dark brown or black.

Citrus greening causes yellowing leaves, often mistaken for zinc or iron deficiency. Fertilizers cannot cure HLB, making accurate diagnosis essential to protect your orchard.

Here is how farmers can easily spot the difference in the field:

Feature	Citrus Greening (HLB)	Zinc / Iron Deficiency
Leaf yellowing	Asymmetrical, blotchy yellowing	Symmetrical, uniform yellowing
Distribution	Random yellow shoots/branches	Usually widespread and uniform
Veins	Veins may become raised and corky	Veins generally remain green
Fruit	Small, lopsided, poor-colored fruit	Usually normal shape and color
Treatment response	No recovery with nutrient sprays	Improves after nutrient correction

Vector Identification: Check tender new flushes for tiny, mottled-brown adults of Citrus Psyllid (Diaphorina citri) held at an inclined angle and yellowish-orange nymphs with white waxy secretions.

Integrated Disease and Vector Management of Citrus Greening (HLB)

Early detection is critical for managing Citrus Greening (HLB). Spotting early symptoms on leaves, fruits, and roots enables immediate action before the disease spreads to neighboring trees.

1. Cultural Management

Weekly monitoring: Inspect young shoot flushes for brown psyllids resting at a 45° angle and tiny orange eggs.
Clean planting material: Replant only certified, disease-free saplings from trusted screenhouse nurseries.
Canopy management: Prune dead branches, seal cut surfaces with Bordeaux paste, and prevent waterlogging.
Windbreaks: Plant tall non-host trees such as Casuarina or Silver Oak along borders.

2. Biological Management

Parasitoid: Tamarixia radiata – major parasitoid of citrus psyllid nymphs.
Predators: Mallada boninensis - larvae feed mainly on citrus psyllid eggs and nymph

Neem-based management: Spray Multiplex Neem Raksha (Azadirachtin 10,000 ppm) @ 1 ml/L every 10–14 days during new flush cycles to repel psyllids.
Entomopathogenic fungi: Spray Beauveria bassiana - Multiplex BABA 2-3 ml/L or 5 gm/L twice at 15 days interval on appearance of psyllid infestation.
Apply Multiplex NISARGA (Trichoderma) - 100 g/plant and Multiplex SPARSHA (Pseudomonas) - 100 g/plant along with compost to strengthen the roots and improve plant vigour.

3. Chemical Management

Micronutrient support: Spray Multiplex PROKISSAN (Zn + Fe + Mn + B) @ 1 g/L, twice a year, covering both sides of the leaves, to supplement micronutrient uptake when nutrient transport through the phloem is impaired.
Psyllid control at new flush: Spray Multiplex NAVTARA 0.5 g/L or Multiplex NAGMIDA 0.5 ml/L or Multiplex NAGLAMBDA-5 1 ml/L or Multiplex NAGPIFONIL
2 ml/L. Rotate insecticides from different chemical classes to prevent resistance development.
Before removal of infected trees: Spray infected trees with contact insecticide like Multiplex BORDER-50 2 ml/L before cutting so psyllids do not scatter to healthy trees.
Spray Multiplex Bactinash-200 – 0.5 g/L to enhance plant defence, boost natural immunity, and improve resistance against disease-causing bacteria.