International Journal of Pure and Applied Sciences and Technology

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1 Int. J. Pure Appl. Sci. Technol., 27(2) (2015), pp International Journal of Pure and Applied Sciences and Technology ISSN Available online at Research Paper Biodiversity of Termites on Farmlands in Ugoniyekorhionmwon, Orhionwmon Local Government Area, Edo State, Nigeria A.B.O. Ogedegbe 1,* and E.V. Eloka 2 1 Department of Science Laboratory Technology, Faculty of Life Sciences, University of Benin, Benin City, Edo State, Nigeria 2 Department of Animal and Environmental Biology, Faculty of Life Sciences, University of Benin, Benin City, Edo State, Nigeria * Corresponding author, (crestedsas_4good@yahoo.com) (Received: ; Accepted: ) Abstract: This study was aimed at evaluating the termite diversity on a 20km stretch of farmland between Ugo and Evboesi villages in Orhionmnowon local government area of Edo state, as well as to determine their pest status. Sampling was carried out every two weeks between May and September, Termites were collected from mound, leaf litter and mound trails. Overall, seven species of termites belonging to two families were recorded. The species recorded include Macrotermes bellicosus, Coptotermes curvignathus, Nasutitermes havilandi, Odontotermes sp., Nasutitermes arboretum, Amitermes evencifer, and Microtermes spp. Among these, M. bellicosus is the most dominant but was not found to attack crops while N. havilandi, Odontotermes sp., Nasutitermes arboretum, Amitermes evencifer, and Microtermes spp. were recognized as pests of various plants. Keywords: Termites, diversity, farmland, Copotermes curvignathus, plants, ecology and insects. Introduction Termites are important components of tropical and sub tropical ecosystems. They are a group of social insects that belong to the Phylum Arthropoda, Class insecta, and Order Isoptera. (Mitchell, 2003). Termites mostly feed on dead plant materials generally in the form of wood, leaf litter, soil or animal dung. Termites are prime example of insects that display decentralized, self organized system, swarm

2 Int. J. Pure Appl. Sci. Technol., 27(2) (2015), intelligence and co-operation among colony members to exploit food sources and environment that could not be available to any single insect acting alone (Osipitan and Oseyemi, 2012). A typical colony contains nymphs (semi matured young), workers, soldiers and reproductive individuals, sometimes containing several egg laying queens. Although termites play a beneficial role in ecology, they are also destructive and are a major threat to crops and household properties (Edwards and Mill, 1986). About ten percent of the estimated species of the insects are economically significant as pests that can cause serious structural damage to buildings, crops or plantation forests. The most important termite pest genera in Africa include Odontermes, Macrotermes, Pseudacanthotermes, microtermes, Ancistrotermes, Allodontermes, Amitermes, Trinervitermes and Hodotermes (Mitchell, 2003). Bong et al. (2012) reported that the wood feeder especially Copotermes curvignathus are the main termite species that infest palm plantation and living Agricultural plants. Termites are highly voracious and destructive and cause substantial damage to homes and other wooden structures in our environment. In severe infestation, structural integrity of a building and the safety of the occupiers could be threatened. Termites live a very cryptic life in the soil or wood, building tunnels, aggregate soil into mounds and transferring particles from different layers, a behaviour that alter the physical structure of Agricultural lands and wood structures (Bong et al., 2012). Crops such as yam and cassava, sugarcane, groundnuts sorghum and maize (Sand 1977, Wood et al, 1980; Logan et al., 1990) are prone to infestation and damage by termites. They also attack grain stores and commonly responsible for mortality of tree, seedlings in forestry and cause considerable damage to buildings and other wooden structures like fence posts and utility poles. Foraging activities in termites is a social procedure (Traniello and Buscher, 1985; Olugbemi and Malaka, 1994), where the activities of hundreds or thousands of individuals are co-ordinated by trail pheromones, which stimulate foragers to leave the nest and orient themselves to a food find. Accordingly, a scouting termite returns to the nest after locating food in a trail laying posture, and discharging sterna gland pheromone (Kaib, 1990). Traniello et al., (1994) stated that exploratory activities for food are randomly carried out by workers of Reticulitermes sp. with rewarded individuals returning to the nest in trail laying posture. The objectives of this study are as follows: i. To collect and identify species of termite found in the study area, using suitable identification keys ii. To identify the pest species of termite found in the study area. Materials and Methods Study Area: Location The study was carried out on a 20km stretch of farmlands between Ugo and Evboesi villages in Orhionmwon Local Government Area of Edo state, Nigeria. The study area was selected because of the heavy presence of termitaria. It is located (lat N and long ) on the southern part of Edo state. Edo state is so located that it forms the nucleus of the Niger Delta. It is bordered by Kogi state to the north and Delta state to the east and south, Ondo state and Ekiti state to the west. Climate The climate is typically tropical with two major seasons:

3 Int. J. Pure Appl. Sci. Technol., 27(2) (2015), The wet (rainy) season which last from April to November 2. The dry (harmattan) season which last from December to March. Topography Soil type in the area is a red-yellow kind of Ferrasols. Vegetation and Land Use The natural vegetation of the area consists of Rainforest. The land use of the area is mostly for agricultural use. Materials The materials used include a brush, 70% alcohol in a bottle, hand lens, dissecting microscope and a white paper. Sampling Method Sampling was done during the rainy season of the year 2012 (between May to September, 2012). Five farms were randomly selected for sampling chiefly due to the heavy presence of termitaria. Sampling was also carried out on uncultivated areas of the study sites and this was done every two weeks within the sampling period. Termites were collected from different habitats such as mounds, weed residue, under leaf litter, under opaque bark of trees and logs. Termites were also collected from unhealthy plants. Vials of collected termites were labelled and all possible observations on their habitat including the mound characteristics or trail pattern were noted. Termites were collected with the aid of a brush as they rush out of their mounds when the top were cut open with a matchet. Preservation The collected termites were preserved in 70% alcohol and taken to the laboratory for identification. Identification Termites were identified using various identification keys present in the museum of the department of Animal and Environmental Biology, Faculty of Life Sciences, University of Benin. Identification was done with the aid of a hand lens and a dissecting microscope. Most of the specimens were identified to the species level based on the morphology of the soldier caste. Most of the features used include: colour appearance, shape of mandibles, shape of head capsule and labrum, number of abdominal segments, number of antennal segments, type of mandible, number of bristles on labrum, number of bristles near the fontanel, presence of teeth on mandibles. These features were compared with the works of Roonwal and Chhotani (1989) and Thapa (1981). Results and Discussion Overall, seven species of termites belonging two families were recorded from the study area. The species recorded include those that made trails on plant and therefore recognized as pest species. The species recorded include:

4 Int. J. Pure Appl. Sci. Technol., 27(2) (2015), Macrotermes Bellicosus The identification of this species was based on the soldier caste. The head is very large. Length of head with mandibles is between 6 to 8 mm. the head is conspicuously distended. Mandible is strong, fully developed and sabre shaped. Pronotum saddle shaped with a distinct anterior lobe. Labrum with an anterior translucent lobe. Eye is absent. Behaviourally, they are very aggressive, build large epigeal mound, and are relatively large species. It belongs to: Family: Termitidae Sub-family: Macrotermitinae Genus: Macrotermes Species: bellicosus Name: Macrotermes bellicosus Soldiers of Macrotermes bellicosus (Actual size 1cm) Mound of Macrotermes bellicosus 2. Coptotermes Curvignathus This species was collected from trails made on tree trunk and is therefore recognized as a pest species. The identification of this species was based on the soldier caste. They have brownish-yellow, ovalshaped head capsule with head capsule with scattered bristles. They have long sabre shaped slashing mandibles and are strongly incurved at the apical. The left mandible has three crenulations at base while right mandible is without crenulation. Labrums are yellowish in colour and have a distinct pair of long bristles on the tip and few bristles on the disc. They also have large fontanelle with two long bristles at the rim. The antenna are sixteen segments and the abdomen have ten segments.

5 Int. J. Pure Appl. Sci. Technol., 27(2) (2015), Behaviourally, they excrete a white fluid from their fontanelle when disturbed or attacked. The species belong to: Family: Rhinotermitidae Sub-family: Coptotermitinae Genus: Coptotermes Species: curvignathus Name: Coptotermes curvignathus Soldier (left) and worker (right) of Coptotermes curvignathus (actual size 2mm) Mound of Coptotermes curvignathus 3. Nasutitermes Havilandi This species was detected based on their mud trails from the ground to tree trunk. The species was identified based on soldier caste. The head (without rostrum) is ovallike and width is longer, wider than length. Their mandibles have been reduced to nasus. The head reddish-yellow to brownish yellow with a pair of bristles on posterior of the head and four short bristles on side of rostrum base. Dorsal profile of the head capsule is nearly straight. Rostrum is short and cone shaped and the tip of the rostrum is reddish-brown and darker than the head. Nasus without rudimentary teeth. They have ten abdominal segment and thirteen antennal segments. Behaviourally, they are glue squirting termite. They are relatively small species with the worker being larger than the soldier. The species belongs to: Family: Termitidae Sub-family: Nasutitermitinae Genus: Nasutitermes Species: havilandi Name: Nasutitermes havilandi

6 Int. J. Pure Appl. Sci. Technol., 27(2) (2015), Soldier (left) and worker (right) of Nasutitermes havilandi (Actual size 2mm) Trails of Nasutitermes haviladi 4. Nasutitermes Arboreum This species built an arboreal carton nest on tree branches. The identification was also bases on the soldier caste. The head (without rostrum) are sub- circular. Dorsal profile of head capsule show a shallow concave at the middle. It is larger than Nasutitermes havilandi. Behaviourally, they show similar features with Nasutitermes havilandi. The species belongs to: Family: Termitidae Sub-family: Nasutitermitinae Genus: Nasutitermes Species: arboreum Name: Nasutitermes arboretum

7 Int. J. Pure Appl. Sci. Technol., 27(2) (2015), Soldier (left) and worker (right) of Nasutitermes arboretum (Actual size 3mm) Arboreal mound of Nasutitermes arboreum 5. Odontotermes sp. These species were collected on a mound built on the decaying wood. The identification was based on the soldier caste. Head is reddish brown, labrum light reddish brown, antennal light brown with yellow tinge at the base, dark brown distally. Rest of the body yellow with brownish tinge. Head with a few bristles along the periphery. Postmentum with few bristles in the anterior half. Pronotum, legs and abdomen sparsely hairy with a few bristles. Head broadly oval and narrowed anteriorly. Post mentum much longer than broad. Antennal with 16 segments, second nearly twice as long as third and forth combined. Labrum tongue shaped, lateral side slightly convex, converging anteriorly into a rounded tip. Mandibles long, slender, tips slightly incurved, left mandible with a prominent anteriorly directed tooth near the base. Pronotum is saddle shaped. The species belongs to: Family: Termitidae Sub-family: Odontotermitinae Genus: Odontotermes Name: Odontotermes sp.

8 Int. J. Pure Appl. Sci. Technol., 27(2) (2015), Worker of Odontotermes sp. Soldier of Odontotermes sp. Trails of Odontotermes sp. A total of seven termite species were recorded from the study area. Five of the seven species were found to attack various trees. They include Nasutitermes havilandi, Nasutitermes arboretum, Amitermis evencifer, Microtermes sp. and Odontotermes sp.; Odontermes sp. and Nasutitermes havilandi were detected based on their mudtrails from the ground to tree trunks and are therefore called interface feeders. Nasutitermes arboreum builds its nest on tree branches and are therefore known as an arboreal nesting termite. Copotermes curvignathus build their nest on decaying trees, hence they are wood feeders. Macrotermes bellicosus build large epigeal mound which is the main land feature of the study area. M. bellicosus are soil feeders and appear not to attack crops. In Nasutitermes spp., the mandibles are reduced and non functional. Instead the soldiers have nasus, an enlongated projection of the fontanelle and their way of defence is by squirting irritating chemical substances through it (Krishnak and Weesner, 1970; Collins, 1984). Besides having a sclerotized head, soldiers of Coptotermes curvignathus have a frontal gland that discharges a defensive secretion through a frontal pore. This secretion can be toxic or repellant to intruders such as ants, or tacky and entangle their legs and antenna. Macrotermes bellicosus and Odontotermes sp. have their soldiers considerably bigger in size and have defensive adaptations such as enlarged mandibles and stopperlike heads (Krishnak and Weesner, 1970).

9 Int. J. Pure Appl. Sci. Technol., 27(2) (2015), Macrotermes bellicosus are the most dominant species found in the study area. They build large epigeal mound which characterize the land form of the study area. This could be attributed to the species being a voracious feeder, feeding on various organic matter as well as feeding on the soil. Throughout tropical Africa, several species of Macrotermitinae consume grass litter as a significant part of their diet and the most common of these species belong to the genera Macrotermes, Odontotermes and Pseudacanthotermes (Wood, 1991). This species also builds underground tunnels to enhance their foraging activities. Their soldiers are very aggressive and considerably large with well developed mandibles which look like a scissors. This aggressiveness and the high defensive mechanisms of the soldiers could account for the large number of individuals in their colony. Despite the pest status of some termite species recorded, they also play a very important role in the ecosystem. Termites are considered to be major agents of woody matter and soil breakdown in lowland tropical ecosystem (Wood and Sand, 1978; Bignell and Eggleton, 2000). In this study, Coptotermes curvignathus were recorded from the base of a decaying palm tree, hence playing a role in decomposition process, while M. bellicosus are considered an ecosystem engineers because of their bioturbating activities in an attempt to build their nest. They also enhances the nutrition status of the area especially areas around the mound (Holt and Lepage, 2000). Jouquet et al. (2004) also observed that through the impact on the soil by termites, their biogenic structures constitute patches in the landscape where the availability of soil nutrients for plants is improved. Amongst insects, Brown (1991) identified termites as potentially one of the most important indicator taxa, not least because they are at the ecological centre of many tropical ecosystems (Wilson, 1992). Termites can achieve very high population densities; for example, in the forests of southern Cameroun, termites are one of the most numerous of all arthropods group (Watson et al., 1997), with abundance of up to 1000 m-² and live biomass densities of up to 100 g m-² (Eggleton et al., 1996). As the dominant soil arthropods detritivores, termites are important in the decomposition process; this is seen in the case of Macrotermes and Coptotermes found in the study area and thereby play a central role as mediators of nutrient and carbon fluxes (Jones, 1990; Bignell et al., 1996). They exhibit a wide range of dietary, foraging and nesting habits, with many species showing high level of resource specialization (Wood and Sands, 1978; Collins, 1989; Bignell and Eggleton, 1996). Their influence on decomposition processes at any site is likely to be governed to a large extent by the species composition of the local termite assemblage. In contrast to the work of Bigger (1996) and Munthali et al. (1992) that Macrotermes spp have been a serious pest of some agricultural plants and tree plantations especially against cassava, this study shows that Macrotermes bellicosus does not constitute a major pest in the study area. One of the major disadvantages caused by this species was the presence of their mounds which occupied most of the farmlands. Though not found on plants, they tend to attack the base of crops planted close to their mound. In this manner, they are assumed to be an opportunistic pest. Coptotermes curvignathus is recognized as a pest of agricultural and forestry tree species, causing economic damage to both mature and young plants. This study is in support of the work of Tho and Kirton (1992), Tho (1992), and Kirton et al. (1999). The pest status of C. curvignathus found in the study area is in accordance with the work of Harris (1957) where he identified C. curvignathus, Schedorhinotermes longirostris and Globitermes globosus as pests. In a maize cassava intercrop in the humid forest zone of south western Nigeria, Macrotermes spp. were the major culprit (Umeh and Ivbijaro, 1997). Though few works have been done on the diversity of Nigerian termites, high incidence of Macrotermes has been recorded. Nasutitermes spp. are among the termites found in the study area that have been accorded little recognition despite their pest status. Of the five species of Coptotermes known from Peninsular Malaysia, three are known to enter buildings (Kirton et al., 1999). Coptotermes kalshoveni and C. curvignathus occasionally affect houses.

10 Int. J. Pure Appl. Sci. Technol., 27(2) (2015), The latter is primarily a pest of agricultural, forestry and urban tree species, causing the death of both young and mature trees (Kirton et al., 1999). Bong et al., (2012) reported that the wood feeder especially Copotermes curvignathus are the main termite species that infest palm plantation and living agricultural plants. Because of the economic importance of termites found in the study area, indigenous populations of the area have adopted many measures to control the effects of termite infestation. Some of the measures are typically local and include the use of human faeces, use of batteries as well as the destruction of the mound to remove the royal nest. The human faeces and batteries are poured into the mound after the top has been cut open. This kills most of the workers and soldiers. This was so common in the study area as there were many dead termite mounds in the area. This is in contrast with the modern method of termite control measures. Plants and plant products were reported to be useful and desirable tools in pest management programs against termites because they are effective and complement for the actions of natural enemies (Ascher, 1993). The use of wood ash and locally available plants containing substances toxic or repellent to termites has often been suggested on the basis of long-established local practice (Wardell, 1987). Wood ash heaped around the base of the trunk has been recorded as preventing termite infestation of coffee bushes. Wood ash is also reported to repel termites from date palms, to protect stored yams and maize, and to be effective in protecting tree seedlings if mixed into plant nursery beds or applied in a layer below polythene planting tubes (Logan et al., 1990). In contrast, application of wood ash at the base of Grevillea robusta seedlings was reported to be ineffective against Macrotermes bellicosus. This disparity may be attributed to variability in termite species, method of application or wood species used for producing ash. Therefore studies aimed at verifying the potential benefits of using wood ash for termite management in agro forestry are necessary. Cowie et al. (1989) pointed out that the use of wood ash in termite control has not been evaluated rigorously, and that its efficacy remains speculative. A basic knowledge of pest biology and ecology is a prerequisite for adequate pest management. Such information is crucial to the design and success of control measures and even to the initial evaluation of the need for control (Logan et al., 1990). Plants and plant products were reported to be useful and desirable tools in pest management programs against termite because they are effective and complement for the actions of the natural enemies (Ascher, 1993). Many plants have developed effective defence against termites and in most ecosystems, there is observable balance between the growth of plants and the feeding of termites (Xie et al, 1995). Defence is typically achieved by secreting anti feedant chemicals (such as oils, resins and Lignins) into the woody cell wall. This reduces the ability of termites to efficiently digest the cellulose. Termites are strongly repelled by some toxic materials to the extent that they become disoriented and eventually die from starvation rather than consume cross treated samples (Peterson and Wilson, 2003). Conclusion Conclusively, more advances on the improvement of termites controls through the use of plants and plant products is necessary because of their effectiveness and environmental friendliness. This work also tends to create some awareness on pest species and potential pest species of termites found in the study area and the need for appropriate pest management.

11 Int. J. Pure Appl. Sci. Technol., 27(2) (2015), References [1] K.R.S. Ascher, Non convectional insecticidal effects of the pesticide available from Neem tree, Archive of Insects Biochemistry and Physiology, 22(1993), [2] M. Bigger, The biology and control of termites damaging field crops in Tanganyika, Bulletin of Entomological Research, 56(1996), [3] D.E. Bignell and P. Eggleton, Termites in ecosystems, In T. Abe, D.E. Bignell and M. Higashi (eds.), Population Dynamics of Termites, Termites: Evolution, Sociality, Symbiosis and Ecology, Dordrecht, The Netherlands: Kluwer Academic Publishers, (2000), [4] D.E. Bignell, P. Eggleton, W.A. Sands, N.A. Mawdsley, J.H. Lawton, T.G. Wood and N.C. Bignell, The diversity, abundance and biomass of termites under differing levels of disturbance in the Mbalmayo Forest Reserve, Southern Cameroon, Philosophical Transactions of the Royal Society of London, 351(1996), [5] J.C.F. Bong, P.J.H. King, K.H. Ong and N.M. Mahadi, Termite assemblages in oil palm plantation in Sarawak, Malaysia, Journal of Entomology, 9(2) (2012), [6] K.S. Brown, Conservation of neotropical environments: Insects as indicators, N.M. Collins and J.A. Thomas (eds.), In: The Conservation of Insects and Their Habitats, Academic Press, London, UK, (1991), [7] N.M. Collins, The distribution of soil microfauna on the west ridge of Gunung Mulu, Sarawak, Oecologia, 44(1980), [8] N.M. Collins, The termites (Isoptera) of the Gunung Mulu national park, with a key to the genera known from Sarawak, Sarawak Museum Journal, 30(1984), [9] R.H. Cowie, J.W.M. Logan and T.G. Wood, Termite (Isoptera) damage and control in tropical forestry with special reference to Africa and Indo-Malaysia: A review, Bulletin of Entomological Research, 79(1989), [10] R. Edwards and A.E. Mills, Termites in Buildings: Their Biology and Control, East Grinstead, Reontokil Limited, UK, (1986), [11] P. Eggleton, D.E. Bignell, W.A. Sands, N.A. Mawdsley, J.H. Lawton, T.G. Wood and N.C. Bignell, The diversity, abundance and biomass of termites under differing levels of disturbance in the Mbalmayo Forest Reserve, Southern Cameroon, Philosophical Transactions of the Royal Society of London, Series B, 351(1996), [12] W.V. Harris, An introduction to Malayan termites, Malaysian Nature Journal, 12(1957), [13] J.A. Holt and M. Lepage, Termites and soil properties, In: T. Abe, D.E. Bignell and M. Higashi (eds.), Termites: Evolution, Sociality, Symbiosis, Ecology, Kluwer Academic Publishers, Dordrecht, Netherlands, (2000), [14] J.A. Jones, Termites, soil fertility and carbon cycling in dry tropical Africa: A hypothesis, Journal of Tropical Ecology, 6(1990), [15] P. Jouquet, N. Boulain, J. Gignoux and M. Lepage, Association between subterranean termites and grasses in West African savanna: Spatial pattern analysis shows a significant role of Odontermes pauperans, Applied Soil Ecology, 27(2004), [16] Kaib, Intra and inter-specific chemical signal in the termite Shedorhinotermes production sites, chemistry and behavior, In: F.G. Gribakin, K. Wiese and A.V. Popov (eds.), Sensory System and Communication in Arthropods: Advances in Life Sciences, Birkhauser Verlag, (1990), [17] L.G. Kirton, V.K. Brown and A. Azmi, The pest status of the termite Coptotermes curvignathus in Acacia mangium plantation: Incidence, mode of attack and inherent predisposing factors, Journal of Tropical Forest Science, 11(1990), [18] A. Krishnak and F.M. Weesner, Biology of Termites, Academic Press, New York, (1970), 643. [19] J.W.M. Logan, R.H. Cowie and T.G. Wood, Termite control in Agriculture and forestry by non chemical methods: A review, Bulletin of Entomological Research, 80(1990), [20] T.G. Miles, Proposed Taxonomy of the Order Isoptera, University of Toronto Press, (1998),

12 Int. J. Pure Appl. Sci. Technol., 27(2) (2015), [21] J.D. Mitchell, Termites as pest of crops, forestry, rangeland and structures in Southern Africa and their control, Sociobiology, 40(2003), [22] D.C. Munthali, C.A. Kaunda, C.B. Nyirenda, C.C. Chipeta and J. Logan, The major insects pests, plant diseases and weeds affecting subsistence farmers crop in the southern Malawi, Project, University of Malawi, Chancellor College, (1992), 169. [23] B.O. Olugbemi and S.L.O. Malaka, Effects of food on recruitment activities in Microcerotermes fuscotibialis, Journal of Scientific Research and Development, 1(1994), [24] A.A. Osipitan and A.E. Oseyemi, Evaluation of the bio-insecticidal potential of some tropical plant extracts against termites in Ogun state, Nigeria, Journal of Entomology, 9(2012), [25] C.J. Peterson and E.J. Wilson, Catnip essential oil as a barrier to subterranean termites (Isoptera: Rhinotermitidae) in the laboratory, Journal of Economic Entomology, 96(2003), [26] W.A. Sands, The role of termites in tropical agriculture, Outlook Agriculture, 9(1977), [27] Y.P. Tho, Termites of peninsular Malaysia, L.G. Kirton (ed.), Forest Research Institute Malaysia, Kepong, Malaysia, Malaysia Forest Records, 36(1994), [28] Y.P. Tho and L.G.A. Kirton, Survey of termite attack in Bahau conifer plantation, Peninsular Malaysia, Journal of Tropical Forest Science, 10(1992), [29] B.L. Thorne and J.M. Carpenter, Phylogeny of dictyoptera, Systematic Entomology, 17(1992), [30] J.F.A. Tranielo and C. Buscher, Chemical regulation of polyethism during foraging in the Neo-tropical termite Nasutitermes costalis, Journal of Chemical Ecology, 11(1985), [31] J.F.A. Tranielo, S.K. Robson, M. Lesnak and R. Kothandapani, Organisation of searching in subterranean termites Reticulitermes spp, Annual Meeting of the Entomological Society of America, Dallas, Texas, (1994), [32] V.C. Umeh and M.F. Ivbijaro, Termite abundance and damage in traditional maize-cassava intercrops in south-western Nigeria, International Journal of Tropical Insects Science, 17(2007), [33] R.V. Varma and P.R. Swaran, Diversity of termites in a young Eucalyptic plantation in the tropical forests of Kerala, India, International Journal of Tropical Insects Science, 27(2007), [34] D.A. Waller and J.P. La Fage, Nutritional ecology of termites, In: F. Slanky and J.G. Rodriguez (eds.), Nutritional Ecology of Insects, Mites and Spiders, Wiley and Sons, New York, (1987), [35] D.A. Wardell, Control of termites in nurseries and young plantations in Africa: Established practices and alternative courses of action, Commonwealth Forestry Review, 66(1987), [36] J.A.L. Watson, B.M. Okot-Kotber and C.H. Noirot, Caste Differentiation in Social Insects, Pergamon Press, Oxford, New York, (1985), 405. [37] E.O. Wilson, The effects of complex social life on evolution and biodiversity, Oikos, 63(1992), [38] T.G. Wood, The agricultural importance of termites in the tropics, Agricultural Zoological Revelation, 7(1996), [39] T.G.A. Wood, A.R. Jonhnson and C.E. Ohiagu, Termite damage and crop loss studies in Nigeria: A review of termite damage, loss in yield and termite (Microtermes) abundance at Mokwa, Tropical Pest Management, 26(1980), [40] T.G.A. Wood and W.A. Sands, The role of termites in ecosystems, In: M.V. Brian (ed.), Production Ecology of Ants and Termites, Cambridge University Press, Cambridge, UK, (1978), [41] Y.S. Xie, P.C. Fields, M.B. Isman, W.K. Chem and X. Zhang, Insecticidal activities of Mehatoosendan extracts and toosendanin against three stored products, Journal of Stored Products Research, 31(1995),