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Need for Generating Baseline Data for Monitoring Insecticide Resistance in leaf Webber cum Fruit Borer, Pempelia morosalis (Saalm Uller), the Key Pest of Biofuel Crop, Jatropha curcas.
Regupathy,
A.
Expert- Crop protection Science Advisory Board,
Biofuel Research & Development Centre,
Coimbatore-641029
India
Ayyasamy,
R.
Department of Entomology, Faculty of Agriculture,
Annamalai University,
Annamali Nagar-608002
India
While exploring the energy alternatives, biofuels, viz., ethanol from sugarcane and biodiesel derived from the oil bearing plants like sunflower, canola, rapeseed, Pongamia, mahua etc. can be used as a substitute or an additive to diesel. Out of the current annual consumption of 127 million tonnes of crude oil, 70 percent is imported. Forty million tonnes of diesel are consumed in a year constituting 40 percent of all petro-products (Soumitra Biswas et. al., 2006 ). Due to spiraling price of crude oil many nations including India are looking for alternatives. Out of various biofuel sources, the Jatropha curcas is considered to be the best-bet as far as India is considered for the following reasons:
1. It is adapted to a wide range of climates .It is grown as live fence to protect agricultural fields from damage by live stocks in most of the states in a variety of agro climatic conditions .
2. It can grow almost in any type of soil viz., gravelly, sandy, saline and even on the poorest stony soils and rock crevices (ITCOT, 2004).
3. The gestation period is low. The plant start yielding in second year and the economic yield stabilizes from the 4-5th year onwards. The plant is a perennial shrub and may live for 50 years with an average effective yielding time of 50 years (Soumitra Biswas et. al., 2006).
4. It is drought resistant, and does extremely well even with low rainfall. Reasonable production with little inputs in marginal lands is ensured. It is estimated that out of 146 million hectares of wasteland , 33 million hectares can be reclaimed for Jatropha cultivation. (NBSSLP, 2004) apart from the arable land that could be used for Jatropha cultivation.
5. Scope for more employment opportunities for the millions of farmers in small scale farming system vogue in India.
The Planning commission recommends allocation of INR1400 crores (US $ 3,000 million) for the promotion for three years (Chitra shanker and Dhyani, 2006). Joint ventures between UK- India based corporate sectors are promoting Jatropha cultivation in India. At present they have plans to bring one lakh (0.1 million) hectares under Jatropha cultivation in Tamil Nadu, Andhra pradesh and Chattisgarh states. The joint ventures supply seedlings, provide technical guidance and assure buy back of seeds (Soundariya Preetha. 2006). To provide technical guidance, they have set up Research and Development Centres to take up research activities to tackle emerging problems with large scale cultivation.
In Virudhunagar district of Tamil Nadu, one million seedlings are raised this year in eight centers for distribution under India Government Afforestation project to promote Jatropha for biodiesel (Anonymous, 2006).
The crop was earlier projected as less prone to damage, perhaps due to use of wild varieties as live fence especially in paddocks and dry lands as cheaper means of fencing in scattered patches. Serious damage by Nephopteryx larvae was observed and first time was reared at Pusa and Mandalay (Hampson, 1912). Scutellarid bug, Chrysocoris purpureus was recorded in North western provinces, Sikkim, Calcutta, and Assam and several parts of South India including Pondicherry (Puducherry) (Kershaw and Kirkaldy, 1908). The garden Jatropha was reported to be affected by sucking pests like tailed mealy bugs Ferrisaina (Ferrisia) virgata, C., Jatropha Scale : Hemilecanium imbricans N. and neem Scale: Pulvinaria maxima G (Ayyar , 1940), leaf and flower webber cum fruit borer, Salebria (Pempelia) morosalis (Saalm Uller), the castor semilooper, castor semilooper, Achaea janata L. (on Euphorbia pilulifera) (Beeson, 1941). More than 40 species of insects affecting Jatropha has been reported (Grimm and Fuhrer, 1998)
With taking up Jatropha as regular monocrop in continuous stretches not only in marginal lands but also in arable lands with high yielding, high fertilizer responsive cultivars, outbreak of pests can be anticipated. Reports of pest occurrence started appearing. Apart from P.morosalis and A. janata, the polyphagous tobacco cut worm, Spodoptera litura (Fabricius) is found to affect this crop (Robinson et. al., 2004) and the incidence was to the extent of 60 to 70 percent in Madhya Pradesh (Meshram and Joshi, 1994). In Jhansi, P.mormoralis and Scutellarid bug, Scutellera nobilis Fabr. are considered as major pests causing great concern (Chitra shanker and Dhyani, 2006). While visiting the farmers fields in Virudhunagar district and crops maintained by Research and Development Centers of Corporate sectors in Coimbatore, the senior author observed the incidence of P. morosalis, S.nobilis, F.virgata, Calotropis leaf hopper bug (Green striped leaf hopper bug), Eurybrachis tomentosa F., grape-vine thrips, Rhipiphorothrips cruentatus H, and Chilli muranai mite, Pol phagotarsonemus latus Banks. Among these P. latus and P. morosalis are emerging as major problems in Tamil Nadu. Manoharan et. al., (2006), reported more than a dozen pests occurring in Jatropha planatations in Udumalpettai, Erode and Mettupalayam areas of Tamil Nadu.
Among the various pests listed above, P. morosalis is specific to Jatropha and reported to affect a few forest species like Desmodium gangeticum, Flemingia sp., and Uraria lagopides, (Beeson, 1941) and not occurring on field crops grown in India. Considering the history of forest pests becoming the pests of field crops subsequently due to reduction of forest habitat and monoculture, P. morosalis may likely to become regular pests with extension of area and perennial nature of Jatropha plantations. The adult moth is gray in colour with snout like labial palpi in the head with hyaline hind wings. The male is slightly smaller than the female with pointed abdominal tip. The total oviposition period of the female was recorded as 4.61 days. The sex ratio of leaf webber was 1.2:1 (male: female). On an average the developmental period from egg to adult emergence was 42.34 days with a high adult emergence of 80.17 percent. Adult longevity of female was 7.25 days while male 5.67 days exhibiting a sex ratio of 1.2:1 (male: female) (personal communication from Dr. Gunathilagaraj). The pupal period is 7-9 days in June to August (Beeson, 1941).
During our regular field visits the greenish brown/brownish green caterpillars were observed webbing the leaves and feeding on leaves remaining in the leaf web. At flowering they bore into peduncle and fruits which show galleries made of silk and frass. The caterpillar bores into the fruits throwing out faecal matter. The greenish larvae turn pinkish at the time of pupation. It pupates on the fruits. The larvae are seen under a cover of silk, frass or excreta, which extend between flowers/fruits.
For management of these pests at present major focus falls on chemical insecticides, though a dipteran parasite and spider Stegodyphus sp. were reported as natural control agent in Jhansi (Chitra shanker and Dhyani, 2006). The mass culture and release technology are yet to be perfected. At present Tamil Nadu Agricultural University (Paramathma et. al., 2004) recommends spray of endosulfan. However most of the farmers under the influence of pesticide dealers may apply an array of insecticides as is in vogue for the management of pests affecting other field crops. Repeated use of chemicals may likely to induce insecticide resistance. For effective pest managemen , detection and continuous monitoring of insecticide resistance are essential. Monitoring of resistance involves comparison of LD50 or the slopes of dose-response curves between field and susceptible reference populations. The reference populations are maintained in the laboratory without exposure to insecticides. In most practical situation the best monitoring method is the use of discriminating/ diagnostic dose (DD) i.e. the dose that kills 99 percent of susceptible individuals (Roush and Miller, 1986.). Sometimes a susceptible (local) population is not available, DD fixed elsewhere is taken as reference as with the case with H. armigera. The DD based on LD 99 for susceptible NRI (Natural Resources International, U.K. and Australia susceptible strains are used. This situation can be avoided in the case of P. morosalis as the pest exposure is nil.
The objective in resistance monitoring is to exaggerate the differences between susceptible and resistant individuals such that frequency of misclassification is greatly reduced (ffrench-constant and Roush, 1990). For estimating resistance level in a population, the initial base-line level of susceptibility is essential so that, comparisons can be made in future (Hopkins et al., 1984). For successful monitoring programme the base-line susceptibility to different insecticides must be estimated separately for each species in the complex. The laboratory population which has not undergone any exposure to insecticides provides the advantages of totally susceptible bench mark for calculating resistance ratios. Resistance in insect pests can be detected by the use of discriminating dose tests. Such detection should be done at the earliest stage of effective pest management. Hence, a suitable monitoring technique is to be developed not only to detect the presence of resistance but also to monitor the changes in resistance frequency to determine whether a programme is effective or not. Information on the the discriminating doses fixed for the important pests like, Helicoverpa armigera Hub., Plutella xylostella L., S.litura , rice leaf folder Cnaphalocrocis medinalis Guene, rice brown plant hopper Nilaparvata lugens Stal., cotton leaf hopper, Amrasca devastans ( Distant) and cotton aphid, Aphis gossypii (Glov.) had been compiled by Regupathy et. al., (2004.) and subsequently for coffee green scale, Coccus viridis Green (Senthilkumar and Regupathy, 2004) Thrips tabaci (Lindeman) (Deepa,et.al., 2005), sugar cane wooly aphid, Ceratovacuna lanigera Z. (Vijayaraghavan and A. Regupathy, 2005), At present the pesticide application is nil or at least, minimal, the exposure of P. morosalis may be nil or negligible. This is the ideal time to get the susceptible population for generating base line susceptibility.
Out of number of bioassay techniques viz., topical assay, leaf residue/ leaf disc, foliar application bioassay, thin layer exposure bioassay/ surface residue vial bioassay, sticky card technique, slide dip bioassay and glass vial technique available, the topical assay will be more suitable for P. morosalis considering the shielded habitat. The topical assay is an old and reliable method. Technical grade insecticide dissolved in less toxic carrier/solvent (acetone) is applied topically (usually 0.5µl) to the dorsal thoracic segments of the test insect with the help of a microapplicator and transferred to petridishes provided with feed. Mortality is assessed after 24h. Control insects were treated with acetone alone. This technique is used for assessing the toxicity fixing diagnostic doses and monitoring insecticide resistance in Helicoverpa armigera and shoot and capsule borer Conogethes punctiferalis Guenee (Renuka, 2003; Rajabaskar, 2003). Topical application used to assess the toxicity to C. punctiferalis can be extended to P. mormoralis as the damage and pest behaviour is similar to C. punctiferalis. Both belong to Family Pyralidae and remains inside the webbings. The method is briefly described below.
Field collected P.morosalis larvae weighing 18 - 22 mg (length 1.2 cm) reared on Jatropha flower heads capsules could be used for bioassay. An aliquot of 1µl of a known dilution of insecticide is placed on the thoracic dorsum of each larva using 1µl repeating dispenser (PB 600 -01, Hamilton Co. Ltd.,) fitted with a 50µl syringe and Rheodyne needle . The control is treated with acetone alone. Not less than 50 larvae per dose need to be used per dose/treatment. Mortality counts are taken 24 h after treatment. To assess the relative toxicity of insecticides median lethal dose (LD50) to P. morosalis is determined. Preliminary range finding tests are made to fix the appropriate dosage range. The log -dose / concentration - response curves are fitted. The DD can be arrived at as detailed by Roush and Muller (1986).
REFERENCES
Anonymous. 2006. India Governmet programme to promote Jatropha for biodiesel. Dinamalar dt August, 6, 2006.
AYYAR, T.V.R., 1940. Hand Book of Eeonomic Entomology for South India. Govt. Press, Madras, 528pp
Ayyasamy, R. and A. Regupathy. 2004. Discriminating dose techniques for monitoring insecticide resistance in India. Resistance Pest Mgmt. Vol. 14.
Beeson, C.F.C. 1941. The Ecology and Control of the Forest Insects of India and the Neighbouring Countries. Forest Research Institute, Dehra Dun, India.1007p.
Chitra shanker and Dhyani, S.K. 2006.Insect pests of Jatropha curcas L. and the potential for their management. Curr. Science 91 (2):162-163.
Deepa S.R., S.V.Krishnamoorthy and A. Regupathy .2005.Assessment of acute toxicity and resistance monitoring of lambda cyhalothrin (Karate Zeon 5 CS) to Thrips tabaci (Lindeman) in Cotton. Resistant Pest Mgmt. 15 (1): 29-32
ffrench - constant, R.H. and R.T. Roush. 1990. Resistance detection and documentation: the relative roles of pesticidal and biochemical assays. pp. 4-38. In: Pesticide Resistance in Arthropods (Eds) Roush, R.J. and B.E. Tabashnik, Chapman and Hall, Newyork and London. 303 p.
Grimm, C. and E. Fuhrer. 1998. Population dynamics of true bugs (Heteroptera) in physic nut (Jatropha curcas) plantations in Nicaragua. J. Appl. Ent., 122: 515-521.
Hampson, F.I. 1912. Proc. 2nd Entl. Mtg. 4: 288.
Hopkins, A.R., R.F. Moore and W. James. 1984. Contact and residual toxicities of pyrethroids and organophosphate compounds to the boll weevil (Coleoptera: Curculoinidae). J. Georgia Entomol. Soc., 19: 27-34.
ITCOT.2004. One Day Seminar on Jatropha- background Material. Industrial and Technical Consultancy Organisation of Tamilnadu Limited, Chennai. Kershaw and Kirkaldy. 1908. Trans Ent. Soc., London. 59.
Manoharan, T., S. Ambika., N. Natarajan and K. Senguttuvan. 2006. Emerging pest status of Jatropa curcus (L) in south India . Ind. J. Agroforestry (In Press)
Meshram, P.B. and K.C. Joshi. 1994. A new report on Spodoptera litura F. Boursin (Lepidoptera: Noctuidae) as a pest of Jatropha curcas Linn. Indian Forester, 1: 273-274.
Paramathma,M., Parthiban,K.T. and Neelakantan,K.S. 2004. Jatropha curcas . Forest College & Research Institute, Tamil Nadu Agricultural University,Coimbatore. 48p.
Rajabaskar, D. 2003. Studies on the evaluation of IPM modules against Conogethes punctiferalis Guenee and Sciothrips cardamomi Ramk. on cardamom. Ph.D thesis. Tamil Nadu Agricultural University,Coimbatore.
Regupathy, Keshav Kranthi, Joginder Singh Arif Iqbal Yidong wu Derrek Russell. 2004. Patterns of Resistance levels in India, Pakistan and China. Proc. World Cotton Research Conference 3, 9-13, March, 2003, Cape Town, South Africa, 1215 -29.
Renuka, S. 2001. Studies on the bioefficacy and dissipation of profenofos applied on cardamom and cashew. Ph.D thesis. Tamil Nadu Agricultural University,Coimbatore.
Robinson, G.S., P.R. Ackery, I.J. Kitching, G.W. Beccaloni and L.M. Hernandez. 2004. Hosts- A data base of the host plants of the world's Lepidoptera. http://www.nhm.ac.uk/entomology/hostplants/
Roush,,R.t. and Miller. G.L. 1986. Consideration for design of insecticide resistance monitoring programmes, J. Econ. Entomol.,79: 293-298.
Senthil Kumar, C.M. and A. Regupathy. 2004. Generating base line data for insecticide resistance monitoring in coffee green scale, Coccus viridis (Green). Resistant Pest Management Newls., 13(5-6).
Soumitra Biswas, Srikanth, G. and Nirmala Kaushik. 2006. Biodiesel: fuel of the future? Biodiesel resources can provide energy security. The Hindu dated August,3, 2006.
Soumitra Biswas, Srikanth, G. and Nirmala Kaushik. 2006. Biodiesel: fuel of the future? Biodiesel resources can provide energy security. The Hindu dated. August, 3, 2006.
Soundariya Preetha. 2006. Turning the underutilized into fertile lands. The Hindu dated September, 26 2005.
Vijayaraghavan, C. and A. Regupathy. 2005.Generating baseline data for insecticide resistance monitoring in sugarcane woolly aphid, Ceratovacuna lanigera Z.. Resistance Pest Mgmt.15(1):25-27
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