Liaphis erysimi Kaltenbach

Liaphis erysimi is widely distributed pest of mustard and other crucifers throughout the country. The whitish green aphid generally appear in cold weather. The attack is severe in those regions where the number of cloudy days are more during the pest activity period. The female deposits 76 to 188 nymphs in its life time at the rate of 3-9 per day. The nymph matures in 8 days time. The apterous females produce several generations and finally the winged forms are produced in summer which get airborne and migrate to the colder regions along with wind.

The attacked leaves curl and in severe cases the plants wither and dry. If the grown up plants are attacked they show severe stunting. Due to secretion of honey dew black sooty mould develops on the infested crop rendering it sickly and blighted in appearance.

Liaphis erysimi is multiplied on mustard plants grown in large field cages 2x2x3 m. First the seeds are sown, as soon as the germinating seedlings reach blossom stage, L. erysimi adults are released which colonises mustard plant. But both the parasitoid and predators can be multiplied on alternative host which in turn is easily multiplied to any numbers in the net house/insectary thus facilitating the rapid multiplication of natural enemies of mustard aphid.