© J. ent. Res., 41 (1) : 85-90 (2017) INTRODUCTION In India 15 different tuber-producing crop species are cultivated, which include the major tuber crops, i.e., cassava and sweet potato; aroid species viz., Colocasia, Amorphophallus, Xanthosomas, Alocacia, and Cyrtosherma; yams such as lesser, greater and white yam; and minor tuber crops, especially, yam bean, coleus, arrowroot and a few others (Anonymous, 2011). The root and tuber crop cultivation is distributed into fve major regional areas: (i) South-western hilly and coastal region, (ii) Southern peninsular region, (iii) Eastern coastal region, (iv) North-eastern region and (v) North-western region (Edison et al., 2006). Major insect pests causing economic damage to different tuber crops in the feld are the sweet potato weevil, sweet potato vine- borer, scale insects, termites, white grubs, spiral whitefy, aphids, thrips, leaf-eating caterpillars, leaf and shoot folders and insect pests under storage that happen to be borers of chips, four beetles and grain moth. (Anonymous, 2011).Studies on insect pests associated with tuber crops cultivated in Rajasthan are scanty hence the present investigation on “Diversity and seasonal incidence of insect pest complex of tropical tuber crops in South-western Rajasthan” was planned with the objectives to study the species diversity of insect pests of major tuber crops at Udaipur and to ascertain the relationship of environmental factors with the insect fauna associated with sweet potato. MATERIALS AND METHODS Studies on the diversity and seasonal incidence of insect pest complex of tropical tuber crops in South- Western Rajasthan was carried out at the Horticulture Farm Rajasthan College of Agriculture, Maharana Pratap University of Agriculture and Technology, Udaipur, Rajasthan. The tropical tuber crops sweet potato, cassava and yam were cultivated as per ICAR sponsored AICRP project on tropical tuber crops. The sampling for insect pests and natural enemies was done in the morning from 8 to 10 AM and in the afternoon from 4 to 6 PM at weekly intervals from 10 plants, selected at random, from each of the cultivated tuber crops. Population of the insect pests and their natural enemies from the tuber crops was estimated by visual counting. Samples of whitefies, Diversity and seasonal incidence of insect pest complex of tropical tuber crops in South-Western Rajasthan S.P. Ganesh, I.P. Mohammad, A.K. Meena * and R. Swaminathan Department of Entomology, Rajasthan College of Agriculture, Maharana Pratap University of Agriculture & Technology, Udaipur - 313 001, Rajasthan, India ABSTRACT Insect pests belonging to 13 families representing 4 orders: Coleoptera (3); Orthoptera (1); Lepidoptera (2); and Hemiptera (7) were recorded on some tuber crops. Chrysomelidae was the most dominant family with the relative density values ranging from 42.85 to 54.54 per cent with highest (54.54%) recorded in yam followed by sweet potato (43.47%). The Shannon and Simpson’s diversity indices were highest for sweet potato 1.65 and 3.724, respectively. The population of chrysomelids, apionids, cicadellids and gryllids exhibited a signifcant positive correlation with the mean atmospheric temperature and relative humidity. Curculionids exhibited signifcant positive correlation with relative humidity. Noctuids and coccinellids showed signifcant negative correlation with relative humidity. Coreids and delphacids and exhibited a signifcant positive correlation with mean atmospheric temperature. Pentatomids exhibited a signifcant negative correlation with mean atmospheric temperature and signifcant positive correlation with relative humidity. Aleyrodids exhibited a signifcant positive correlation with mean atmospheric temperature and signifcant negative correlation with relative humidity. Key words : Tuber crops, Correlation, Diversity indices, Insect pests, Natural enemies. *Corresponding author's E-mail: akmeenaentomology@gmail.com DOI : 10.5958/0974-4576.2017.00014.7