Insect Pests of Fruit, Plantation, Medicinal & Aromatic Crops (2+1)

7. Citrus psylla

7. Citrus psylla - Diaphorina citri Kuwayama. ( Psyllidae : Hemiptera)

Damage

• The nymphs are found congregated on young half open leaves and desap the same.
• The infestation resulted in arresting the growth of the plants.
• Since the insect inject the toxins along with saliva, the leaves and flower buds wilt and die gradually.
• It also acts as vector of citrus virus causing citrus decline disease.
Bionomics

• The adult is brown with its head lighter brown and pointed measuring 3 mm in length.
• A female lays 500 almond shaped orange coloured and stalked eggs on tender leaves and shoots.
• The incubation period is 10-20 days in winter, 4-6 days in summer.
• The nymphs are flat orange yellow in colour and louse like creature.
• The nymphal period is 10-11 days. The females live longer than males.
• There are 8-9 over lapping generation in a year.
Management

• Prune the affected trees and dried shoots periodically prevent the multiplications of psyllids.
• Conserve the natural enemies by avoiding broad-spectrum insecticides.
• Spray neem seed kernel extract 5 % or neem oil 1 % or monocrotophos 36 WSC at 1 ml or quinalphos at 1 ml with 0.5ml teepol / litre of water.
• Spray dimethoate 1675 ml or malathion 1250 ml / ha during February ¬March, May-June and July-August.
• Encourage activities of natural enemies such as Syrphids and Chrysopids.