author(s)
J Kousika and S Kuttalam

abstract
Field experiments were conducted to access the arthropod diversity in tomato ecosystem in tetraniliprole 200 SC sprayed and unsprayed filed. Collections were made using four different methods viz., active searching, net sweeping, pitfall trap and rubbish trap. The treated and untreated fields were divided into 100 quadrats (4 m x 4 m) and five such quadrats were chosen each at random and the entire site was covered during the sampling period. Species richness and diversity was studies by various indices. The result showed that totally 2760 individuals were found out of 1717 and 1043 were found in sprayed and unsprayed, respectively. Under Arachnida ten species and nine genera were recorded. Family Lycosidae (49) was dominant followed by Araneidae (43), Tetragnathidae (22), Oxyopidae (19), Salticidae (17) and two unidentified species. Under Insecta, exopterygotes were the largest group represented by seven orders viz., Orthoptera, Dictyoptera, Odonata, Hemiptera, Isoptera, Dermaptera and Thysanoptera. While endopterygotes were represented by five orders viz., Diptera, Hymenoptera, Lepidoptera, Coleoptera and Neuroptera. From the above indices, it is inferred that maximum number of arthropods was recorded in unsprayed tomato fields than the sprayed fields. Maximum diversity of arthropods was observed during the month of November and minimum during the month of December in most of the diversity indices.