Parasitoid Complex and its Efficacy in the Management of Shot-hole Borer, Scolytus nitidus Schedl. (Coleoptera: Scolytidae) on Apple Trees

Nine species of hymenopterous ectoparasitoids were found parasitizing the shot-hole borer, Scolytus nitidus Schedl. (Coleoptera: Scolytidae) on apple trees in Kashmir. The parasitoids with average coefficient of dominance were: Macromesus harithus Narendran (Pteromalidae) (72,70%), Enrytoma morio Boheman (Eurytomidae) (9.73%), Spathius sp. Nees (Braconidae) (8.74%), Rhaphiteluis macnlatus Walker (Pteromalidae) (6.67%) and Cheiropachus quadrant Fabricius (Pteromalidae) (2.15%). Heydenia indica Buhroo (Pteromalidae), Eupelmus vindex Erdos (Eupelmidae), E. kashmiricus Buhroo (Eupelmidae) and E. valsus Narendran (Eupelmidae) were occasional and arrived late in the development of their beetle host. The parasitization by M. harithuss was the highest (52.88%) while the parasitization by other common parasitoids ranged from 1.75 to 7.08. The parasitoid maximum population was observed during April - May and August - September. Field releases of M. harithuss, Spathins sp., E. morio and C. quadrum made at Bandipora for the management of S. nitidus increased the parasitism from 14.8 to 45.3 per cent, while at Naseem Bagh the increase in parasitism ranged from 15.4 to 41.5 per cent indicating the establishment of parasitoids on shot-hole borer.