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Subject: Entomology × Author: Himangshu Mishra × End date: 2017 × Start date: 2015 × Thesis Type: Ph.D ×
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    ThesisItemOpen Access
    ECOLOGY AND MANAGEMENT OF MOUND BUILDING TERMITES
    (AAU, Jorhat, 2017-07) Himangshu Mishra; Bhattacharyya, Badal
    Study on ecology and management of mound building termites were carried out in Jorhat and Golaghat district of Assam. Ecological studies were conducted at four different habitats viz., forest, agriculture, rural and urban habitat of both the districts during 2015 and 2016 while management of termites in tea ecosystem was conducted in experimental plot under department of tea husbandry and technology, AAU. Sampling in different habitats revealed 8 species of termites from both the districts. Among the 8 different species, 5 species were belonged to Macrotermitinae subfamily, whereas other 3 species belonged to Nasutitermitinae, Kalotermitinae and Amitermitinae subfamily. The genus Odontotermes were found dominant and consisted of four species viz., Odontotermes obesus (Rambur), O. feae (Wasmann), O. parvidens (Holmg. and Holmg.) and O. kapuri (Roonwal and Chhotani) while the remaining 4 species were belonged to different genera and these were Microtermes mycophagous (Desneux), Trinervitermes biformis (Wasmann), Neotermes buxensis (Roonwal and Sen-sarma) and Speculitermes chadaensis (Chatterjee and Thapa). Four different feeding groups of termites were recorded among which soil, litter and fungus feeder were dominantly found. Moreover, out all eight species two termites (O. obesus and O. feae) were dominantly distributed in different habitats of both the district. Morphometric studies of some termite species under Macrotermitinae subfamily revealed that O. feae were comparatively bigger than O. parvidens, M. mycophagous, O. obesus and O. kapuri. Collection of termites from different habitats revealed that higher population of the termite species were recorded from forest habitats than rural, agriculture and urban habitats of both the district. In addition it was also observed that forest habitats had highest mound density per ha (4.42 & 4.35 and 4.50 & 4.40) than rural (3.85 & 3.55 and 3.40 & 3.20), agricultural (3.25 & 3.05 and 3.30 & 3.15) and urban (3.15 & 3.00 and 3.25 & 3.10) sites of Jorhat and Golaghat district respectively. Ecology of mounds were studied through proper observation on nesting patterns of O. obesus and O. feae mounds in different habitats of both the district. Nesting pattern observed in mounds of forest habitats recorded comparatively higher sizes of basal diameter, height, incubation cavities, nursey cell, diameter and depth of the royal chamber from the ground level, moreover the mounds noticed in forest habitats also had higher sizes of length and width of the fungal comb than rural, agriculture and urban habitat of Jorhat and Golaghat. Caste composition recorded in the mounds of different habitats confirmed that higher numbers of worker, soldiers were collected from the mounds of forest habitats. Termite population of O. obesus and O. feae also recorded in the Assam Agricultural University, Campus and the study found fluctuating trend of termite castes in different months during March, 2015 to February, 2016. Correlation of population with mound dimension and weight of the fungal comb revealed that both O. obesus and O. feae showed positively significant correlation with basal diameter [0.982*(0.001) & 0.956*(0.001)], height [0.975*(0.001) & 0.925*(0.001)] and weight of the fungal comb [0.921*(0.002) & 0.925*(0.001)] respectively. Observation on termitophiles and inquilines associated with the mounds of O. obesus and O. feae, stated that scarabaeids and carabids were highly dominant where as staphylids, elaterids, formicids, arachnids and diplopods were moderately dominant termitophiles. Out of different types of inquilines recorded, annelids were highly dominant whereas molluscs and squamets were found moderately and less dominant inquilines. Study on fungal and bacterial colony in the mounds soils of different habitats revealed that, mound soils of forest habitat exhibited higher numbers of bacterial and fungal population than rural, agricultural and urban habitats of both the district. Physicochemical properties of mound soils of different habitat exhibited higher amount of silt (%), clay (%), soil moisture (%), organic carbon (%), available nitrogen (g/kg) and soil microbial biomass (g/kg) than the surrounding mound soil collected from different habitats of both the district. Management of the termites in tea ecosystem revealed that Metarhizium anisopliae registered least number and portion of infestation (13.86 & 12.04% and 14.11 & 12.04%) and showed statistical parity with Heterorhabditis indica treated plant (14.49 & 13.73 and 15.60 & 14.26%) after 30 and 60 days of treatment. The tea plants treated with Jatropha oil 50 EC and Neem oil 30 EC exhibited number of infestation (15.52 & 16.56%) and portion of infestation of (14.60 and 15.36%) while the untreated control plants recorded 38.44 & 37.35 and 40.32 & 39.48 per cent of infestation after 30 and 60 days of treatment respectively.