Komunitas serangga herbivora penggerek polong legum dan parasitoidnya: Studi kasus di daerah Palu dan Toro, Sulawesi Tengah

Hamid, Hasmiandy (2009) Komunitas serangga herbivora penggerek polong legum dan parasitoidnya: Studi kasus di daerah Palu dan Toro, Sulawesi Tengah. PhD thesis, IPB.

PDF - Published Version Download (3746Kb)

Abstract

HASMIANDY HAMID. Comunity of pod borer insects and its parasitoids in legumes: A case study in Palu and Toro, Central Sulawesi. Under supervision of DAMAYANTI BUCHORI, SJAFRIDA MANUWOTO, and HERMANU TRIWIDODO. The abundance and species richness of herbivore insects are not only determined by its host plants, instead it is also determined by its natural enemy complexes. Altitude and habitat types are two environmental factors that may also influence the herbivores as well as its parasitoids. To investigate the influence of these factors toward the abundance and diversity of pod borers, a research was conducted in Palu city (altitude until 90 m dpl) and Toro village, district Kulawi, regency Donggala, about 92 km from Palu (altitude above 700 m dpl). The aim of this research is to study the community structure of herbivore insects and its parasitoid communities. Insect communities studied are the pod borers of various legumes plants, its niche breadth, its herbivore load and parasitoid load of a diverse legum plant community. Pod borers diversity and parasitoid community of Crotalaria striata was studied at different altitude and habitat type. Observations were conducted on the diversity of legum plant species, pod borer herbivores, and its parasitoids that emerge from the legum pod, and the damage level that was caused by herbivores. Special attention was given to C. striata pods at different altittudes and different habitat types. Observations on Crotalaria includes the damage level as well as the herbivore load an parasitoid community structure. Pods were collected from legum plants found in various habitats. For C. striata, in addition to the collection of pods in the Palu and Toro area, an empirical study was also done by planting potted C. striata in different habitat type at Toro. The aim of this study is to understand the influnece of habitat types on the community structures of pod borers and its parasitoids. Three habitat types belonging to agroforestry systems (cacao and its shaded trees) and one open habitat was used. The result from this research showed that legum pods are predominantly supporting small numbers of herbivores, with the exception of C. striata and Mastersia bakeri that support four different insect herbivores. High abundance and wide distribution of C. striata pod can influence herbivore insect abundance especially Eucorynus crassicornis. The composition of insect herbivores in legum is dominated by E. crassicornis that can attacked pods from various legum (12 species), but are found predominantly associated with C. striata, while the parasitoid composition is dominated by parasitoid Eurytoma spp which attacks E. crassicornis. There are not difference in herbivores insect community between Palu and Toro as well as natural and modification habitat. Difference in insect composition are shown in parasitoid community. Damage level of herbivores insect higher in Toro than Palu. There are no difference in the production of seeds (total seeds per pod) that are produced by Crotalaria at Palu and Toro. However, the numbers of seeds remained from pods that have been attacked are lower in Toro compared to Palu. For natural and modification habitats, seed production and seed total remained in attacked pod showed that natural habitats lower than modification habitats, but not for damage level. Habitat types also affects insect abundance, with open area having a higher proportion compared to other types. Higher abundance was also shown for the parasitoid. Damage level of C. striata pod showed higher at open area habitat than other habitats. Nonetheless, the diversity of insect herbivores and its parasitoid community are lower in open habitat.

Actions (login required)

View Item