Indian Journal of Entomology 83(2021) Online published Ref. No. e20115 DoI No.: 10.5958/0974-8172.2021.00001.8 TERMITES IN IMPORTANT CROPS AND THEIR MANAGEMENT ABHISHEK RANA*, R S CHANDEL, K S VERMA AND MANISHKUMAR J JOSHI Department of Entomology, CSKHPKV, Palampur 176062, Himachal Pradesh *Email: [email protected] (corresponding author) ABSTRACT Termites are polyphagous pests causing economic losses to a large number of crops worldwide. Among 3105 species of termites, about 185 species are considered as pests globally. The termites that belong to family Termitidae are known to cause great losses to agricultural and horticultural crops. In India, Odontotermes obesus (Rambur) and Microtermes obesi Holmgren damage crops in both vegetative and reproductive stages, especially wheat, maize, barley, pulses, oilseeds, vegetables, fruits, plantations, sugarcane, cotton etc. The damage can lead to almost 100% yield losses, especially if it occurs in early stages of crop growth. Over the past 60 years, many insecticides from several chemical groups have been used for the management of termites globally. But no single method of control provides a permanent solution. Therefore, IPM approaches viz., cultural, mechanical, biological (Beauveria bassiana, Metarhizium anisopliae, Steinernema carpocapsae, Heterorhabditis indica, Bacillus theuringiensis, Pseudomonas fluorescens etc.) methods, and botanical extracts must be integrated with insecticides in farmer’s field to reduce termite problems. Key words: Microtermes, Odontotermes, Termitidae, insecticides, botaniclas, biological control, IPM, cereals, pulses, oilseeds, horticultural, plantation crops, losses Termites are polyphagous pests and one of the most economically important subterranean species (28 destructive of agricultural, horticultural, agroforestry species) (Paul et al., 2018). Among soil inhabiting/ and plantation crops (Rashmi and Sundararaj, 2013; mound building termites, O. obesus is the most Kashyap et al., 1984; Paul et al., 2018). These are damaging, destroying developing and maturing stages found in a wide range of terrestrial environment and of almost all crops (Pardeshi et al., 2010). distributed throughout the tropical, subtropical and Around 70% of termite species belong to a single temperate regions of the world infesting various crops family, Termitidae (Kumar et al., 2013). Termites are (Anonymous, 2009). Termites pose a serious threat of great importance in recycling woody and other plant to different crops grown in areas where water stress material. But at the same time, they become economic conditions prevail (Mahapatro and Sreedevi, 2014). The pests when they start destroying crops (Meyer, 2005). termite species that attack crops have a wide variety of Mostly, termites prefer dead plant material but when lifestyles ranging from small simple colonies to large their preferred food is exhausted and once the main societies with highly organized complex nest systems. crop is available, they shift to the main field through an Depending on habits and habitats, termites can be irregular network of large interconnected mud galleries classified into wood dwellers and ground dwellers. The and start feeding on living plant parts including roots. wood dwellers comprise of species inhabiting damp and They tunnel through plant stems and eat cellulose rich dry woods. The ground dwellers are categorized into roots, causing the plants to become stunted. Such plants subterranean and mound builders (Pearce, 1997). The can easily be uprooted from the soil (Mahapatro and major mound building, economically important species Sreedevi, 2014; Paul et al., 2018; Chhotani, 1980). Due are Odontotermes obesus (Rambur), O. redemanni to the presence of certain protozoa in their digestive tract (Wasmann) and O. wallonensis (Wasmann). The (Hindgut) which possess enzymes, they are capable of major subterranean species are Heterotermes indicola digesting cellulose (Mahapatro and Sreedevi, 2014; (Wasmann), Coptotermes ceylonicus (Vietnam), C. Abdulahi, 1990). heimi (Wasmann), Odontotermes homi (Wasmann), Microtermes obesi Holmgren, Trinervitermes biformis Presently, the termites are being managed with (Wasmann) and Microcerotermes beesoni Snyder insecticides viz., imidacloprid 70WS, imidacloprid (Rajagopal, 2002). Among subterranean species, the 48FS, thiamethoxam 70WS, thiamethoxam 30FS, genus Coptotermes contains the largest number of fipronil 0.3GR and bifenthrin 10EC, as recommended by 2 Indian Journal of Entomology 83(2021) Online published Ref. No. e20115 Central Insecticides Board and Registration Committee citrus, vegetables, spices and fruit crops (Roonwal, in India. In other countries, many other insecticides 1979). Among cereal crops, wheat and maize are most are being tested and used in different crops. Some of often damaged (Shrivastava et al., 2014). Severe losses these are used for spraying purpose whereas, some on wheat and sugarcane in northern India, maize, are used for seed treatment. However, concern about groundnut, sunflower and sugarcane in southern India, safety, environmental pollution and reduced efficacy tea in eastern India and cotton in western India are of insecticides has increased the need for suitable IPM known. Pardeshi (2007) observed that crops which were approaches making insecticide use as a last resort. But already attacked by aphids, white grubs, and hoppers before practicing this adequate knowledge of pest status were more vulnerable to attack by termites. and the range of material attacked is essential. This paper reviews information on termites’ infestation in Sometimes, crop yields are reduced drastically different agricultural, horticultural and plantation crops because the losses inflicted at or near maturity cannot be and their management by different methods with special compensated (Verma and Kashyap, 1980). Such losses reference to IPM practices. impede food security and threaten the livelihoods of marginal farmers (Demissie et al., 2019). Infestation Global status and economic importance due to termites was observed up to 20-25% in rainfed About 3,105 species of termites in 330 genera and up to 10% in irrigated crops (Sharma et al., 2009). (Kumar et al., 2013) distributed over 12 families Such losses are more pronounced in agronomically (Engel et al., 2009) and 14 subfamilies (Varshney, and physiologically poor soils. In African countries, 2007) are presently recognized from all over the over 90% of the damage in agriculture and forestry is world with about 185 considered to be pests (Verma attributed to members of the Macrotermitinae which et al., 2009). Around 300 species under 37 genera build the large termitaria, and thus the reputation of under seven families had been reported from the termites as pests is associated with the presence of Indian region (Murthy et al., 2015) of which about termitaria in crop fields (Sileshi et al., 2009; Abdulahi 12% species (35 species) are known to damage et al., 2010). Globally, the estimated loss due to termite agricultural crops. Termites that belong to the families damage is about 50 billion USD (Subekti et al., 2015), Hodotermitidae (Anacanthotermes and Hodotermes), although estimates vary considerably by the cropping Kalotermitidae (Neotermes), Rhinotermitidae systems followed in different geographical regions. (Coptotermes, Heterotermes and Psammotermes), and Termite infestation and losses caused in important crops Termitidae (Amitermes, Ancistrotermes, Cornitermes, are discussed below: Macrotermes, Microcerotermes, Micromeres, Infestation in cereals Odontotermes, Procornitermes, and Syntermes) cause great loss to agricultural crops (Anonymous, 2000). Maize, sorghum and millets: Many species Two species, O. obesus and M. obesi account for almost of termites had been reported to attack maize, but 80% of total losses in South Asia. In India, termites are Microtermes spp, Macrotermes spp., Odontotermes widely distributed in red, sandy loam, lateritic and red spp. and Allodontermes spp., were found to cause loam soils (Varshney, 2007). Gujarat and Rajasthan economic losses to the crop (Joshi et al., 2005; Wood provide an interesting area for study on the fauna over et al., 1980; Vikram Reddy et al., 1994; Hillocks et al., diverse ecosystems (Table 1). 1996). O. obesus causes economic losses sporadically to maize crop in lower areas of Himachal Pradesh and Heinrichs and Barrion (2004) suggested that the other adjoining states of India (Kumar et al., 2001). plants which are being stressed by biotic (insects pests A gradual increase in termite damage can be noticed and diseases) and abiotic factors (drought, nutrient from November with a decrease in the intensity of rains deficiency etc.) attract more damage by termites. (Agarwala, 1955). According to Loko et al. (2019), the Termites are becoming a serious threat to all major erratic rainfall is the most important factor favouring crops such as cereals (rice, wheat, barley, maize, millet termite infestation in maize fields. Termites attack the and sorghum), pulses, oilseeds, vegetables, fruits stem of maize plants at the ground level, covering with (guava, citrus, banana, mango, papaya, grapes etc.), an earthen sheet up to 10 cm height from the base. When sugarcane and cotton (Rathour et al., 2014; Lin et al., the earthen sheet is removed, a hole is found at the base 2015; Sen-Sarma, 2000). In the dryer parts of India, which is completely eaten a few centimeters upward and infestation by termites had been reported in maize, downward, and filled with