Faunal composition of scarab beetles and their hosts in Assam

Abstract

Field investigations were conducted in the Instructional cum Research Farm and Horticultural Orchard of Assam Agricultural University, Jorhat, to monitor the population of foliage-feeding scarab beetles on eight different host plants during 2010-2012. The highest numbers of beetles were collected from sthal-padma (Hibiscus mutabilis) (1579 numbers) followed by agar (Aquilaria malaccensis) (1526 numbers) and guava (Psidium guajava) (1348 numbers). The lowest number was found on jute (Corchorus sp.) (370 numbers). The host plants, viz., rose (Rosa chinensis), ber (Ziziphus jujuba), Silikha (Terminalia chebula), and Soalu (Litsaea polyantha) recorded 1143, 1143, 1065, and 930 beetles, respectively. The present investigation also revealed 13 numbers of new host plants of scarab beetles, viz., devil tree (Alstonia scholaris), albizia (Albizia odoratissima), dalchini (Cinnamomum zeylanicum), cocoa (Theobroma cacao), indigo (Indigofera zollingeriana), mango (Mangifera indica), Assam lemon (Citrus lemon), green gram (Vigna radiata), jamun (Syzygium cumini), rain tree (Samanea saman), mast tree (Polyalthia longifolia), jackfruit (Artocarpus heterophyllus), and drumstick (Moringa oleifera). Through scouting 20 species of scarab beetles were recorded, of which, Sophrops iridipennis, Anomala perplexa, Anomala dussumieri, and Adoretus renardi are new records from Assam.