Abundance of Insects using Light Traps in the Nursery Area at State Agricultural Polytechnic of Samarinda

It is known that insect species amount to 686,000 or 72% of the total species of the animal world. And when viewed in terms of human interests, insects can be divided into 2 groups, namely insect pests and useful / useful insects (Partosoedjono, 1985). The purpose of this study was to identify and determine the abundance of insects to know the diversity of species, frequency of presence (fluctuation), abundance and dominance in the nursery area at State Agricultural Polytechnic of Samarinda. The expected results of this study are to determine the number and abundance and density of insect populations both the number (n) and composition in the nursery area at State Agricultural Polytechnic of Samarinda. The research was carried out for 3 months which included literature study, field orientation, preparation of tools and materials, data collection, data processing and preparation of research reports. Insect capture was carried out using the light trap method as a lure for insect gathering at night, insects were identified by equating, matching or comparing with literature books (Key to Insect Determination). Data analysis was carried out by calculating the abundance of species based on the Species Dominance Index (Di) according to Heddy and Kurniati (1996), and knowing the level of dominance based on the Important Value Index (INP %) according to Curtis (1959) in Bratawinata (1998).  The Results of Research During 1 Month of Data Collection in the Field Obtained the Following Results:  There is an abundance of 115 insect individuals consisting of 18 species. Of the 18 species consisted of 4 orders namely Orthoptera, Lepidoptera, Diptera and Coleoptera. Of the 4 orders consists of 10 families namely Blattidae, Gryllidae, Acrididae, Arctiidae, Drosophyllidae, Cerambycidae, Scarabaeidae, Lampyridae, Chrysomelidae, and Coccinellidae. And there are 18 genera namely Blatta, Gryllus, Valanga, Pareuchaetes, Drosophylla, Xenolea, Pterolophia, Clepmetopus, Epepeotes, Epicasta, Rhytidodera, Apomecyna, Leucopholis, Photuris, Aphthona, Zygograma, Chrysolina and Brachiacantha.  Based on the Dominance Index (Di) there are species that occupy the most dominant position, namely by Pareuchaetes insulata (21.74%), Photuris lucicrescens (15.65%), Blatta sp (12.17%), Aphthona nonstriata (11.30%), and Gryllus pensylvanicus (9.57%).  Based on the frequency of presence, 2 species have a high frequency of presence, namely Blatta sp (4 frequencies, 10.26%), and Photuris lucicrescens (4 frequencies, 10.26%).  Based on the value of the Index of Important Value (INP) there are 6 most dominant species namely Pareuchaetes insulate, Photuris lucicrescens, Blatta sp, Aphthona nonstriata, Gryllus pensylvanicus and Xenolea tomentosa. There are 6 sub-dominant species and 6 species that are not dominant.