White Grubs (Lachnosterna longipennis and L. coracea):

The grubs initially feed on rootlets/roots and then on tubers. The first stage grubs feed on live roots while the second and third instar grubs make large, shallow and circular holes in the tuber and render them unfit for marketing.

Control:

A majority of beetles (white grub adults) found in Western Himalayas are attracted to the light source hence electric or petromax light traps may be operated for mass-collection. Wild shrubs and other hosts of beetles growing in/around the potato fields should be removed. Repeated ploughing before monsoon (April-May) exposes the grubs and pupae. They may be handcollected and destroyed. Flooding of the fields, for 7-10 days, adopting suitable crop rotations and applying well rotten FYM helps in controlling the pest. Applying Phorate 10G or Carbofuran 3G @ 2.5- 3.0 kg a.i. /ha in furrows at planting or near plants base during earthing time is more effective.