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PESTS OF PULSES - RED GRAM & CHICKPEA :: Major Pests :: Grass Blue Butterfly

3. Grass blue butterfly: Euchrysops cnejus (Lycaenidae: Lepidoptera)


Distribution and status:  Throughout India. Regular pest

Host range
:  Blackgram, peas, redgram and lablab.

Damage symptoms:
Buds, flowers and young pods with boreholes and presence of slug like caterpillar.

The adult butterfly is blue, medium sized with 5 black spots in the hind wings and two black spots in the inner margin.  It lays 60-200 eggs singly on stem, pod, and leaf petioles.  They hatch in 2-10 days.


The pale green or yellow larva measures about 13 mm in length with a red line and short black hairs on the body.  It feeds on flowers; flower stalks and enters the pod.  The entry hole on the pod is plugged with excreta.  The larval period is 10-21 days with four instars.  It pupates in soil or between fallen leaves and debris of the plant for a period of 5-12 days.

Management for Blue butterfly

    • Discourage dense or close planting.
    • Avoid early or late sowing.
    • Dig soil regularly during the period of infestation to kill larvae and pupae.
    • Pick and destroy the larvae, pupae & adults.  
    •  Release  egg parasitoid Trichogramma sp.
    • Conserve larval parasitoids Aploymia sp., Hyperencyrtus lycaenephila, Listrodromus crassipes.
    • Chemicalcontrol measures are the same as redgram pod borer