Symptoms:

There are several species of hoppers damaging mango crop all over India.  Enormous numbers of nymphs are found clustering on the inflorescence during spring, sucking the sap.  The infested flowers shrivel, turn brown and ultimately fall off.  On attaining maturity the hoppers leave the blossoms and move on the leave.  Swarms of adults are commonly seen hovering in mango groves and sitting on all plant parts.  The hoppers excrete honeydew that covers the inflorescence, leaves and fruits encouraging black sooty mold, which affects photosynthetic activity of leaves and market quality of fruits.

Control

 a) At high hopper density (>4 hoppers/ panicle)

A spray of Imidacloprid 0.005% or Lambda cyhalothrin 0.0025% at early panicle emergence and a spray at pea-size of fruit stage will reduce the hopper density. 

 

b) At low hopper density (< 4 hoppers/ panicle)

If population is low to moderate, azadirachtin 0.3% @ 2 ml/litre can limit hopper build up. One should be wary of hoppers even after fruit development as a sudden influx can affect fruit quality. Subsequent spray should be only with Carbaryl 0.2%.