Odontotermes Obesus Research Articles

The symbiotic agriculture of fungus-farming termites can collapse if they fail to prevent invading weeds. Previous studies suggest a role for symbiotic fungistatic microbes in bringing about weed control. However, how termites employ these microbes to suppress fungal weeds without affecting the fungal cultivar remains unknown. We show that the fungus-farming termite Odontotermes obesus uses specific behaviors to remove, isolate, and suppress the growth of the fungal weed Pseudoxylaria, primarily by encasing it with soil boluses containing fungistatic microbes. These behaviors efficiently suppress the weed without affecting the crop. This integration of specific behaviors with termite-derived microbes appears to be the proximate mechanism of how microbes are topically used by termites to confine the weed while keeping the crop unaffected.

Tea is a vital plantation crop in India with a significant global economic impact. Termites pose a substantial threat to tea production. This report characterises and compares the fungal communities present in the arboreal nest of the live wood-eating tea termite Microtermes obesi, called the gallery, and the above-ground nest of the scavenging tea termite Odontotermes obesus, called the mound, using DNA metabarcoding and culture-based identification methods. The metabarcoding analysis showed higher species richness and diversity in the arboreal gallery soil compared to the mound soil. The phylum Ascomycota was predominantly found, with Eurotiomycetes and Dothideomycetes being the most abundant classes in the mound and Sordariomycetes and Saccharomycetes in gallery soil. Culture and ITS sequencing identified unique lignocellulolytic fungal species like Xylogone sp., Lasiodiplodia sp., Arthrinium sp., Phanerochaete sp. in the mound soil and Cunninghamella sp., Scedosporium sp., Purpureocillium sp., Gongronella sp. in the gallery soil. Genera like Penicillium and Trichoderma were abundantly obtained through the studies involving both DNA metabarcoding and culture-based analyses of all soil samples. The presence of lignocellulolytic fungi suggested their role in pre-digesting plant material, aiding termite's survival. These findings highlighted the value of combining culture-independent and culture-based methods to explore fungal adaptation to specific ecological niches and their ecological functions in an agroecosystem.

Field efficacy of entomopathogenic nematodes (EPNs), Heterorhabditis bacteriophora were evaluated to ensure the feasibility of native isolate of entomopathogenic nematode to be used in the bio-control of termite (Odontotermes obesus) infestation. EPNs were applied as a soil drenching method at two different doses up to three times of application on termite mound. Results revealed that H.bacteriophora were able to infect O.obesus and cause mortality up to 58.30% within the mound. The Per cent mortality O. obesus were highest with H.bacteriophora at 5.0×109 IJs/mound, three-time application at one month interval. H.bacteriophora successfully penetrated and reproduced well in both workers and soldiers of O.obesus in all the treatments. After one month of last application of nematode, persistence was better as shown by the mortality of Galleria mellonella larvae (5.2-43.8%).

Aim: To evaluate the virulence and endophytic colonization efficacy of Metarhizium anisopliae and Beauveria bassiana in Dalbergia sissoo seedlings against Odontotermes obesus. Methodology: Termites (O. obesus) were collected from infested wood and acclimatized at 26 ± 2°C and 75 ± 5% RH. Active, uninjured workers were used for bioassays. M. anisopliae and B. bassiana cultures from ICAR-NBAIR were grown on SDA and PDA media, respectively, at 25 ± 1°C. Conidia (1 × 108 conidia ml-1) were suspended in sterile water with 0.05% Triton X-100. Termites were treated using a Potter spray tower, with controls receiving sterile water. Mortality was observed over seven days, and LT50 values were calculated. D. sissoo seedlings were inoculated with fungal suspensions via soil drench and foliar spray. Colonization was assessed by re-isolating fungi from surface-sterilized plant tissues. Results: M. anisopliae showed greater virulence against O. obesus, with a lower LT50 (32.84 hr) compared to B. bassiana (42.48 hr) and a steeper dose-response slope (4.88). Colonization studies revealed the M. anisopliae achieved higher rates in foliage (84.31%), roots (76.36%), and leaves (80.94%) compared to B. bassiana (74.32%, 60.52%, 69.98%, respectively), with significant differences noted in root and leaf colonization (P < 0.001). Interpretation: M. anisopliae demonstrated superior termite control and higher colonization efficiency in D. sissoo seedlings, making it a promising agent for integrated pest management in forest ecosystems. Key words: Beauveria bassiana, Dalbergia sissoo, Endophytic colonization, Metarhizium anisopliae, Termite

Effect of endophytic entomopathogenic fungi (EEPF) in biological control of Odontotermes obesus (Rambur 1842) and their synergistic impact on plant physiological responses

The mound-building termite Odontotermes obesus's queen deposited white and translucent cylindrical-shaped eggs in the royal chamber were transported and deposited in the fungal combs. The mean weight of 100 eggs was 0.01±0.001g. Early and subsequent stages of nymphs were active in the primary and surrounding fungal combs, respectively. A significant portion of the nest inmates were workers. The worker's body and abdomen length were 3.63 ± 0.11 mm and 1.91± 0.15 mm, respectively. The length and width of the head were 1.07 ± 0.02 and 0.94 ± 0.06 mm, respectively. The soldier's right and left mandible lengths varied from 0.65-0.82 (0.76±0.06 mm) and 0.71-0.85mm (0.78±0.05 mm). Dull white alate nymphs possessed prominent wing pads and bulged abdomen. King was present with the queen in the royal chamber, and its mean body length was 8.12±0.33 mm. The queen's body weight ranged from 1.86 - 7.83 g (4.27 ±2.58 g). Key words: Odontotermes obesus, eggs, workers, soldiers, king -queen

The mound-building termite Odontotermes obesus (Rambur) belongs to the subfamily Macrotermitinae, family Termitidae, and Order Isoptera. Termites are ecosystem engineers and involve bioturbation, especially in tropical and subtropical regions. O. obesus is widely distributed and considered a significant pest of agricultural and horticultural crops, forest plantations and woodworks. The colony inmates deposit the excretory pellets (partially digested cellulose and lignin) in the unilocular fungal chambers of the nest to cultivate the fungal garden (round or irregularly shaped) for further digestion. The combs are situated close to the base of the mounds. The mean weight of the fungal comb in a dissected mound was 3.68 ± 1.56 kg. The eggs, early developing nymphs, workers and soldiers were in the combs. The ratio of workers, soldiers and nymphs varies. The investigation revealed that the fungus comb, contains 44.65 % moisture with 4.99 pH and 0.56mmhos/cm EC. Further, comb possesses 11.53% organic carbon, 0.84 % total nitrogen, 0.03% of total phosphorus, 0.089% of total potassium, 85 meq/100g of exchangeable calcium, and 21 meq/100g of exchangeable magnesium. Key words: Odontotermes obesus, faecal pellets, organic carbon, unilocular fungal combs

Biowaste-derived nanoparticles (NPs) are gaining attention for their biocompatibility, environmental friendliness, and affordability. This study synthesized silver NPs (Ag NPs), zinc oxide NPs (ZnO NPs), and silver-doped zinc oxide NPs (Ag/ZnO NPs) using termite wing biowaste (Odontotermes obesus). The synthesized NPs were characterized by UV-visible spectroscopy, FTIR, SEM-EDX, XRD, and atomic force microscopy (AFM), confirming successful biosynthesis and purity. AFM provided 3D profiling of the average sizes of 28.4, 19.6, and 11nm for Ag NPs, ZnO NPs, and Ag/ZnO NPs, respectively. Among these three NPs, Ag/ZnO NPs showed superior antioxidant activity in DPPH (86±3.61%), ABTS (76±1.5%), and nitric oxide assays (77±1%). In vitro studies demonstrated their significant antibacterial and anticancer potential against Escherichia coli, Staphylococcus aureus, and HeLa cells, with >80% cell viability reduction at 100µg/mL. These findings highlight the potential of Ag/ZnO NPs as antioxidants, antibacterial agents, and anticancer agents, warranting further in vivo studies for biomedical applications.

Termites are the agroeconomic and polyphagous pests. In this study, the effect of five botanicals, Datura metel, Catharanthus roseus, Lantana camara, Calotropis gigantea and Azadirachta indica against the workers of Odontotermes obesus was evaluated. Among these rapid mortality rate is recorded with Catharanthus roseus (3.89 at 1st hour) followed by Datura metel (2.89 at 1st hour). Both Catharanthus roseus and Datura metel showed the mortality within 4 hours. Which is followed by Azadirachta indica, Lantana camara. Keywords- Termites; Datura metel; Catharanthus roseus; Lantana camara; Calotropis gigantea and Azadirachta indica.

Social insects such as ants, bees, wasps, and termites exhibit complex social structures and cooperative behaviors that rival those of vertebrates in sophistication. India, with its rich biodiversity and varied ecosystems, has contributed significantly to the understanding of insect sociality. This paper reviews key Indian studies on insect colony organization, caste differentiation, communication mechanisms, and cooperative behavior. Special attention is given to indigenous species such as Apis cerana indica, Odontotermes obesus, and Diacamma indicum, highlighting their unique adaptations. The paper also explores the evolutionary implications of eusociality and discusses how Indian research enhances global theories of cooperation and social evolution.

Chlorfluazuron was discovered and developed in the Asia-Pacific region by Ishihara Sangyo Kaisha (ISK) Japan and launched in the 1980s. The compound is a benzoylphenyl urea and acts as an insect growth regulator by inhibiting chitin synthesis in insects. Subsequently, Ensystex developed chlorfluazuron for termite baits, with test results demonstrating that it met key criteria for good termite baits. The first commercial introduction of a chlorfluazuron-based bait in the Asia-Pacific region occurred in Australia in 2002. Since then, the bait has been registered in most major countries across the region. Several studies have been published on the efficacy of the bait against termite species, including those from both the Heterotermitidae and Termitidae families. Tested species include Coptotermes formosanus Shiraki, C. acinaciformis (Froggatt); C. gestroi, Wasmann; C curvignathus Holmgren; Heterotermes indicola (Wasmann), Macrotermes gilvus (Hagen), Microcerotermes losbanosensis (Oshima), Globitermes sulphureus (Haviland), and Odontotermes obesus (Rambur). This article presents a brief history and use of chlorfluazuron baits, considering its importance in the fast-growing urban environment of the Asia-Pacific region.

Fungus-growing termites, like Odontotermes obesus, cultivate Termitomyces as their sole food source on fungus combs which are continuously maintained with foraged plant materials. This necessary augmentation also increases the threat of introducing non-specific fungi capable of displacing Termitomyces. The magnitude of this threat and how termites prevent the invasion of such fungi remain largely unknown. This study identifies these non-specific fungi by establishing the pan-mycobiota of O. obesus from the fungus comb and termite castes. Furthermore, to maximize the identification of such fungi, the mycobiota of the decaying stages of the unattended fungus comb were also assessed. The simultaneous assessment of the microbiota and the mycobiota of these stages identified possible interactions between the fungal and bacterial members of this community. Based on these findings, we propose possible interactions among the crop fungus Termitomyces, the weedy fungus Pseudoxylaria and some bacterial symbiotes. These possibilities were then tested with in vitro interaction assays which suggest that Termitomyces, Pseudoxylaria and certain potential bacterial symbiotes possess anti-fungal capabilities. We propose a multifactorial interaction model of these microbes, under the care of the termites, to explain how their interactions can maintain a predominantly Termitomyces monoculture.

– Green nanotechnology has widespread applications in various biomedical science fields. In this research paper, green-synthesized silver Nanoparticles, prepared by using Nicotiana rustica extract, were characterized using digital calorimeter, scanning electron microscopy and FTIR. This study thoroughly investigated the insecticidal efficacy of medicinal plants, Nicotiana rustica. Different extraction methods were used and their efficacy with and without nanoparticles was compared. FT-IR analysis indicated the involvement of carboxyl (-C=O), hydroxyl (-OH), C-N stretching of aromatic amines or NO2 symmetric stretching and amine (-NH) functional groups of tobacco leaf extract in the preparation of Silver Nanoparticles. SEM analysis showed that AgNPs is widely distributed in some areas and has irregular and circular shapes that have different diameters with average diameters of, for example, 54.79 nm and 66.05 nm. The focus of the study was on investigating various parameters such as mortality rates, insect survival rates, adult emergence and development stages after treatment periods of 24, 42 and 72 hours. The termite repellent efficacy was significantly higher in treatments with nanoparticles, but the differences were not significant (p>0.05).

Botanical pesticides are of great importance in Integrated Pest Management (IPM). Extracts of different plant parts are used for deterring and killing the various life stages of insects. Most of the oils produced by plants contain bioactive compounds with insecticidal properties. Neem oil containing azadirachtin is an established insecticide and insect repellent. Use of synthetic pesticides for wood preservation leads to environmental pollution and health hazards to human beings and other living organisms. To avoid these problems neem, Azadiracta indica (A.Juss.) plant oil was used in this study and gave better results. The weight loss of card boards treated with neem was less like chlorpyrifos treated cardboards. Gravimetric measurements of cardboards shown 18.34gm and 16.85 gm weight which after 30 and 60 days of exposure to A. indica oil indicated that plant oil has potential effects like conventional pesticides like chlorpyrifos which showed the18.72 and 18.63 gm of weight in cardboards after 30 and 60 days of exposure. The P values was 0.036457 and 0.016527 for cardboards exposed to two treatments after 30 and 60 days respectively which is highly significant.

Bioefficacy of methanol and aqueous extract of Ricinus communis L. against Indian white termite, Odontotermes obesus (Isoptera: Termitidae)

Field experiment carried out at the Entomology Instructional Farm, JNKVV-College of Agriculture Rewa, MP during rabi season 2018-19 revealed that incidence of the chickpea pod borer Helicoverpa armigera. Population range of pod borer during different weather weeks varied between 0.30 and 1.89 larvae/mrl (April 2nd week and March 2nd week respectively). Peak larval population of Helicoverpa armigera was recorded in 2nd week of March (11 standard weeks). A weak negative correlation was observed with the maximum relative humidity and minimum relative humidity correlation, -0.172 and -0.595 respectively and a non significant positive correlation with maximum temperature, minimum temperature and rainfall. The respective r was found to be 0.306, 0.391 and 0.269. In district Rewa, MP, India the insect-pests of chickpea and their natural enemies during rabi the total seven species was recorded in Chickpea in which six pests minor in nature and one major pest Chickpea pod borer (Helicoverpa armigera). Termite (Odontotermes obesus Ram.), White grub (Holotrichia consanguinea Bl.), Black aphid (Aphis craccivora Koch), Grasshopper (Chrotogonus trachypterus Blan.), Semilooper (Autographa nigrisigna L.), Cut worm (Agrotis ipsilon Huf.) are minor in nature. Seven natural enemies found during field investigation i.e. lady bird beetle (Chilomenes sexmaculata Fab.), lady bird beetle (Coccinella septempunctata L.), Praying mantis (Mantis religiosa), Dragon fly (Crocothemis servilia Drury), Campoletis parasitoid (Campoletis chlorideae Uch.), Indian mynah (Acridotheris tristis L.), King crow (Dicrurus macrocerus Vie.) in chickpea observed in low to medium population on the crop and to help in reduction of pest population.

Abstract: Termiticidal potential of methanol and aqueous leaves extract of Jatropha gossypifolia Linn. were studied against Odontotermes obesus. The plant leaves were dried, powdered and extracted with methanol and aqueous solvent in soxhlet apparatus for 24 hrs. The 20 termites were exposed to various concentrations from 9.0 to 14.5 mg/ml) of methanol and of aqueous plant extract of Jatropha gossypifolia and percent mortality were recorded after 24 hrs. The termiticidal activity of leaves extract of Jatropha gossypifolia were (LC10 = 9.8220 mg/ml, LD50 = 10.093, LC90 =12.667 mg/ml) in methanol and (LC10 = 11.984, LC50 = 13.195, LC90 =14.531 mg/ml) in aqueous solvent respectively. Results revealed that the mortality was increased with increasing in concentration of the plant extracts. The methanol solvent extract of Jatropha gossypifolia showed higher termiticidal property against Odontotermes obesus. Statistical variance, 95% confidence limits and regression equations are presented.

Abstract The research was conducted in the pristine ecosystems of the GKVK campus of the University of Agricultural Sciences, Bengaluru, Karnataka, India. The O. obesus mound displayed a conical structure with one or multiple hollow conical turrets. The upper part of the mound exhibited a smaller circumference compared to the lower portion. The inner wall of the mound was characterized by a smooth surface with small pinhead-like depressions (pinholes). The number of pinholes was observed to be higher in the upper region and lower in the lower area. At the base of the mound, the turret wall thickness was substantial and rigid, measuring between 1.8-4.2 cm with an average thickness of 3.1±0.78 cm. A noteworthy positive correlation (r = 0.855) between the increase in the circumference of the base and the height of the mound was observed. The study findings revealed that the influence of the base circumference on the mound's height (r2 =0.73) was 73 percent, underscoring the significant role of the base circumference in determining the mound's height. Additionally, the study indicated that a unit increase in the base circumference corresponded to a 2.00 unit increase in the height of the mound.

Phenol 2,4 di-tert butyl, Phenol 3,5 di-tert butyl and isoaromadendrane epoxide: Termiticidal compounds isolated from Lantana camara L.

A comprehensive study was undertaken by collecting 51 samples of termites between July and October 2021 in three distinct zones within the Bhiwani district to analyze the termite diversity of the Bhiwani, Haryana region. The interplay of aeolian dunes characterizes the Bhiwani district?s ecological landscape. Nestled within the Indo-Gangetic alluvial plain, the Loharu Banger zone, and the ruggedness of the Aravalli Hills provide three distinct niches for termite diversity. The study sheds light on the intricate tapestry of termite life inhabiting these diverse ecological niches. Sample identification exhibited termites? affiliations to two prominent families, Termitidae and Rhinotermitidae and three subfamilies, Amitermitinae, Macrotermitinae, and Coptotermitinae. Further, delving into the taxonomy unveiled a total of ten termite species inhabiting the various locations across the three ecological regions of Bhiwani district including Coptotermes sp., Microtermes mycophagus Desneux, Odontotermes gurdaspurensis Holmgren and Holmgren, Odontotermes redemanni (Wasmann), Odontotermes obesus, Coptotermes kishori, Amitermes belli (Desneux), Microcerotermes sp., Odontotermes guptai Roonwal and Bose, and Odontotermes vaishno Bose. Various diversity indices, including species richness, Simpson?s diversity index, Shannon-Weaver index, and Pielou?s evenness index, were used to determine the relative abundance and distribution of termite species within each zone. These indexes offer a comprehensive view of termite community structure and ecosystem resilience. This pioneering research marks the first-ever documented record of termite biodiversity in Bhiwani district, Haryana. In a region where the study of termites had hitherto been scarce, this endeavor opens doors to a deeper understanding of these soil-dwelling architects of nature. It lays the foundation for future research and pest management strategies in this dynamic ecosystem.. KEYWORDS :Isoptera, Termite diversity, Taxonomy, Pest management, Soil ecology