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Open Access
Biorational management of major pests in brinjal (Solanum Melongena L.)
(Department of Agricultural Entomology, College of Agriculture, Padannakkad, 2014) Gowrish, K R; KAU; Ramesha, B
Brinjal (Solanum melongena L.) is a plant of considerable conomic importance in many tropical and sub tropical parts of the world. It is a popular vegetable grown as poor man’s crop in India. It is a native of India and is grown throughout the country. The brinjal crop is usually infested by a number of pests right from nursery stage till harvest. Among the insect pests, the most important and destructive ones are shoot and fruit borer, Leucinodes orbonalis; epilachna beetle, Epilachna vigintioctopunctata; leaf roller, Antoba olivacea and hairy caterpillar, Selepa docilis. For the management of these pests, the conventional pest management practices often provide unsatisfactory results. Further, the use of chemical pesticide results in insecticide resistance, pest resurgence, destruction of natural enemies and pesticide residue in the harvested produce and related environment and health hazards. Hence, there is an impetus for research and development of eco-friendly and biorational alternative for the sustainable management of major pests of brinjal. A survey was conducted in the three agro climatic regions of Kasargod district viz., low, mid and high land area. The survey revealed that per cent incidence of pests like L. orbonalis, E. vigintioctopunctata and A. olivacea were severe on brinjal in low, mid and high land area of Kasargod district. However, severe infestation of S. docilis was noticed in low land, compared to mid and high land area of Kasargod district. Spinosad 45 SC was found to be effective in controlling the shoot and fruit borer of brinjal during both summer and kharif season. Azadirachtin 1% was found to be most effective in controlling E. vigintioctopunctata adults as well as grubs. It was also found to be effective in reducing mean per cent of leaf infestation during both summer and kharif season. The Bt formulation was found to be highly effective for early instar larvae of A. olivacea. However, for older instar caterpillars, malathion 50 EC was found to be effective during both summer and kharif season. The azadirachtin 1% was found to be highly effective against S. docilis as compared to other treatments during both summer and kharif season. The spinosad 45 SC was safer to natural enemies like predatory coccinellids and spiders in brinjal ecosystem. The yield of brinjal plant was higher in spinosad 45 SC treated plots and a higher return was obtained worth Rs. 2.52 and Rs. 2.67 during both summer and kharif season respectively for every one rupee invested. Effect and compatibility of spinosad 45 SC on entomopathogenic fungi using poisoned food technique under in vitro condition revealed that spinosad 45 SC is not compatible with M. anisopliae and B. bassiana in terms of colony development, sporulation and spore germination. Residue of major and minor component of spinosad 45 SC were below the maximum residue limit.
Open Access
Bioefficacy of neonicotinoid insecticides against insect pests of okra (Abelmoschus esculentus(L.) Moench)
(Department of Agricultural Entomology, College of Horticulture, Vellanikkara, 2014) Jijisha, P K; KAU; Sosamma, Jacob (Guide)
An investigation on “Bioefficacy of neonicotinoid insecticides against insect pests of okra (Abelmoschus esculentus (L.) Moench)” was undertaken in the Department of Agricultural Entomology, College of Horticulture, Vellanikkara, Kerala Agricultural University during 2013- 2014. The study was carried out by conducting two field experiments at the Instructional Farm, College of Horticulture in two seasons viz., April 2013 to July 2013 and October 2013 to January 2014. Two neonicotinoid insecticides - thiamethoxam and imidacloprid - were fieldevaluated for their biological efficiency against major insect pests of okra, safety to naturaenemies, influence on plant growth parameters and terminal residues in okra fruits. The twoinsecticides were applied in three methods viz., seed treatment (ST), two foliar treatments (2FT) and a combination of seed treatment followed by a single foliar treatment (ST+FT). Thetreatments comprised of ST thiamethoxam 30FS @ 3 g a.i. kg -1 (T1) and ST imidacloprid48FS @ 6 g a.i. kg -1 (T2) before sowing, two foliar sprayings ( 2FT) with thiamethoxam25WG @ 25g ai ha -1 (T3) and imidacloprid 70WG @ 25 g a.i. ha-1 (T4) at 15 and 30 daysafter sowing (DAS) and a combination of seed treatment followed by a foliar spraying(ST+FT) with thiamethoxam (T5) and imidacloprid (T6) at 30 DAS. A standard checkinsecticide quinalphos 25EC @ 250 g a.i. ha -1 as two foliar sprayings (FT) at 15 and 30DAS (T7) along with an untreated control (T8) were also included in the field experiment. Both thiamethoxam and imidacloprid were found to be significantly effective than quinalphos against Amrasca biguttula biguttula Ishida in okra. All the three methods of application with thiamethoxam and imidacloprid showed equal effectiveness upto 30 DAS. However, both the foliar treatment and the combination of seed treatment followed by a single foliar treatment with thiamethoxam proved to be equally effective throughout the season to A. biguttula biguttula. Thiamethoxam and imidacloprid by all the three application methods (seed treatment, foliar treatment and combination of seed treatment followed by foliar treatment) were equally effective against Aphis gossypii Glover upto 25 DAS. From 30 to 50 DAS, two foliar sprayings at 25 g a.i. ha -1 revealed a highest reduction of 88.49 per cent in the population of A. gossypii. Two foliar sprayings with imidacloprid 70 WDG @ 25 g a.i. ha-1 at 15 and 30 DAS recorded the lowest population of Bemisia tabaci Gennadius and least leaf damage by Sylepta derogata Fabricius in okra. Thiamethoxam 25WDG with two foliar sprayings (2 FT) @ 25 g a.i. ha -1 at 15 and 30 DAS significantly reduced the shoot and fruit damage by Earias vitella Fabricius. With regard to the impact of thiamethoxam and imidacloprid on natural enemies, two foliar sprayings with thiamethoxam at 25 g a.i. ha -1 showed highest coccinellid population in the first season. In the second season, seed treatment with thiamethoxam @ 3 g a.i. kg indicated the highest population of coccinellids. However, imidacloprid was found to be safer than the standard check quinalphos to coccinellids in both seasons. But the spider population was observed to be relatively less in all the treatments of thiamethoxam and imidacloprid as compared to the untreated control. Thiamethoxam and imidacloprid showed no adverse effect on other predators such as syrphids, chrysoperla and rove beetles in okra field. Thiamethoxam and imidacloprid indicated phytotonic effects on okra plant for they exhibited significant effects on plant growth parameters. Two foliar sprayings of thiamethoxam significantly increased the plant height, number of leaves, flowers per plant, fruit weight and fruit length. Seed treatment with both thiamethoxam and imidacloprid reduced the days for flower initiation. Terminal residue in fruits was below detectable limit at 15 days after spraying in all the treatments with thiamethoxam and imidacloprid.
Open Access
Morphological and biochemical bases of resistance to melon fruit fly, [Bactrocera cucurbitae(Coquillett)(Diptera:Tephritidae) in Bitter gourd(Momordica charantia L.)]
(Department of Agricultural Entomology, College of Horticulture, Vellanikkara, 2014) Manju, Roshni K; KAU; Madhu, Subramanian
A study titled “Morphological and biochemical bases of resistance to melon fruit fly, Bactrocera cucurbitae (Coquillett) (Diptera: Tephritidae) in bitter gourd (Momordica charantia L.)” was undertaken at College of Horticulture, Vellanikkara during 2013-2014 with the objectives of evaluation of the degree of resistance to melon fruit fly in selected accessions of bitter gourd, identification of morphological and biochemical bases of resistance and assessment of the olfactory response of melon fruit flies to fruit extracts of bitter gourd accessions. A field experiment was carried out in Randomised Block Design with ten treatments and three replications at Instructional Farm, Vellanikkara. The treatments consisted of accessions Priya, Preethi, Priyanka, CO-1, VKB-136, VKB-130, VKB-196, IC-0596980, IC-0596981 and IC-0596983. The resistance of bitter gourd accessions to melon fly was evaluated in terms of per cent fruit damage and larval density. The results showed significant variation in fruit infestation among the accessions evaluated. The lowest damage of 9.13 per cent was recorded in VKB-196 followed by CO-1 at 10.17 per cent, both being on par. Four accessions, including Priya (49.08 %), Priyanka (50.99 %), VKB-130 (53.14 %) and Preethi (64.56 %) recorded higher levels of infestation and were on par. Melon fly damage was found to be influenced by the fruit characters of different accessions. Correlation of infestation with fruit characters such as colour, weight, length, width, flesh thickness, spine length, spine form and spine density revealed that spine density and flesh thickness were negatively and significantly correlated with per cent fruit damage (-0.81 and-0.69 respectively) and larval density (-0.74 and -0.69 respectively). VKB-196, which recorded the highest values for flesh thickness and spine density (0.52 cm and 9.83/cm , respectively) recorded the lowest incidence of 9.13 per cent while VKB- 130 with flesh thickness of 0.32cm2 and spine density of 4.81 cm2 recorded higher damage of 53.14 per cent. Analysis of parameters like protein content, moisture content, peroxidase activity and polyphenol oxidase activity showed a negative and significant correlation of peroxidase activity with fruit fly infestation. Studies on olfactory responses of gravid female melon fly to fruit extracts recorded higher response to hexane fruit extract as against aqueous extract. Similarly melon flies showed greater attraction to those accessions which had recorded higher per cent damage, suggesting presence of volatile chemicals which might have mediated response of melon fly towards the accessions. Based on present investigations, VKB-196 and CO-1 may be rated as highly resistant to melon fly, IC-0596983 as resistant, IC-0596981, VKB-136, IC-0596980 and Priya as moderately resistant and VKB-130, Preethi and Priyanka as susceptible. The studies also show that resistance could be mediated by fruit characters like flesh thickness, spine density and peroxidase activity. Sustained efforts could lead to development of melon fly resistant bitter gourd varieties, providing the much needed edge to melon fly management in bitter gourd.
Open Access
Evaluation of entomopathogenic fungi against pest complex of chilli (Capsicum annuum L.)
(Department of agricultural entomology, College of agriculture, Vellayani, 2014) Lokesh, S; KAU; Sudharma, K
An investigation entitled “Evaluation of entomopathogenic fungi against pest complex of chilli (Capsicum annuum L.)” was carried out during 2012-14 at College of Agriculture, Vellayani. The objectives were to evaluate the efficacy of Beauveria bassiana (Balsamo) Vuillemin, Lecanicillium lecanii Zare & Gams and Metarhizium anisopliae (Metschnikoff) Sorokin against pests of chilli, assess the compatibility of the fungi with pesticides and develop products of the fungi. Three fungi viz. Fusarium solani (Mart.) Sacc and Penicillium oxalicum Currie and Thom infecting Aphis gossypii Glover and Isaria javanica (Friederichs & Bally) Brown & Smith infecting Bemisia tabaci Gennadius were isolated and the reports on these insects are new in India. An yeast, Meyerozyma caribbica (Vaughan-Martini, Kurtzman, S.A. Meyer & E.B. O'Neill) Kurtzman & M. Suzuki infecting B. tabaci has been isolated and the report of the yeast is new. The pathogenicity of fungal isolates was evaluated against A. gossypii, B. tabaci, P. latus and S. dorsalis. All the treated insects showed symptoms of infection by all the isolates except Llm. The virulence of the fungi was evaluated @ 108 spores ml-1. At 48 hours after treatment, the highest mortality of 99.97 per cent to A. gossypii was caused by L. lecanii (Ll8). I. javanica caused the maximum mortality of 83.61 per cent to B. tabaci. With respect to P. latus, the highest mortality of 80.65 per cent was recorded in B. bassiana (Bb5a) and it was on par with the mortality in L. lecanii (Ll8) and B. bassiana (Bb21). The effect of all the fungi except L. lecanii (Llm) to S. dorsalis was on par. The LC50, LC90 and LT50 values of the fungal pathogens to A. gossypii, B. tabaci, P. latus and S. dorsalis were worked out. To achieve control of these sucking pests in the shortest period, the field doses fixed for B. bassiana (Bb5a), B. bassiana (Bb21), L. lecanii (Ll8) and M. anisopliae (Ma4) ranged from 1.68 × 108 to 5.10× 109, 1.68× 108 to 5.75× 109, 2.76× 108 to 4.12× 109 and 3.11× 108 to 3.12× 109 spore ml-1 respectively. Talc based products of the fungi were prepared and their shelf life was determined. The cfu observed at 60 days after storage was 1.03× 108 ml-1, 0.44× 108 ml-1, 0.68× 108 ml-1 and 1.18× 108 ml-1 for B. bassiana (Bb5a), M. anisopliae (Ma4), L. lecanii (Ll8) and Bb21 respectively. The compatibility of the fungal pathogens with pesticides was assessed. Dimethoate (0.06%) was the most inhibitory to all the fungal isolates. M. anisopliae (Ma4) was least inhibited by the pesticides. Field experiment was conducted to evaluate the fungal pathogens and newer molecules of insecticides against pests of chilli. The treatments B. bassiana (Bb5a) and L. lecanii (Ll8) @ 20 g l-1 and acetamiprid (0.004%) were found to be on par in reducing the P. latus population. B. bassiana (Bb5a) 20 g l-1 was found on par with acetamiprid (0.004%), spiromesifen (0.02%) and emamectin benzoate (0.002%) in their effectiveness to S. dorsalis at 7 DAT. The fungal isolates did not affect the spider population. The benefit cost ratio was highest for the treatment with B. bassiana (Bb5a) 20 g l-1 (2.62). To conclude, the fungal pathogens viz. B. bassiana (Bb5a and Bb21), L. lecanii (Ll8) and M. anisopliae (Ma4) @ 20 g l-1 are safe, economical and ideal for integration with newer pesticide molecules viz. emamectin benzoate (0.002%), spiromesifen (0.02%) and acetamiprid (0.004%) for management of pest complex of chilli.
Open Access
Insecticide resistance in spotted pod borer, Maruca vitrata 9Fabricius) on vegetable cowpea and its management
(Department of Agricultural Entomology, College of Agriculture, Vellayani, 2014) Pattapu, Sreelakshmi; KAU; Ambily, Paul
A study on “Insecticide resistance in spotted pod borer Maruca vitrata (Fabricius) on vegetable cowpea and its management” was undertaken at College of Agriculture, Vellayani and in the farmer’s field at Kalliyoor and Venganoor panchayaths during January, 2013 to May, 2014. The main objectives were to assess the insecticide resistance in field population of spotted pod borer, M. vitrata, evaluate the efficacy of new generation insecticides against the resistant population and determine the harvest time residues in cowpea pods. A preliminary survey conducted among cowpea growers in Kalliyoor and Venganoor panchayaths of Thiruvananthapuram district revealed control failures in the field population of spotted pod borer due to the continuous application of a single insecticide like chlorpyriphos or lambda cyhalothrin. The survey data served as the benchmark for further studies on the insecticide resistance in M. vitrata. Bioassay was carried out in CRD to assess insecticide resistance in populations of M.vitrata collected from three different locations (location I- field with no previous history of pesticide application, location II- field where less control failures and location III- field where more control failures) using two chemicals viz. chlorpyriphos and lambda-cyhalothrin at different doses. Results revealed that population collected from location-I was found to be susceptible for both the chemicals with resistance ratio-1, population collected from location-II to be moderately resistant with a resistant ratio of 2.28 and 2.38 and population from location-III to be resistant with resistance ratios of 2.93 and 7.94 for chlorpyriphos and lambda-cyhalothrin respectively. Laboratory experiments conducted to evaluate the efficacy of new generation insecticides viz. novaluron - 0.015 per cent, flubendiamide - 0.01 per cent, spinosad - 0.015 per cent, emamectin benzoate - 0.002 per cent, indoxacarb 14.5 per cent + acetamiprid 7.7 per cent SC- 0.09 per cent, acephate 50 per cent + imidacloprid 1.8 per cent SP - 0.20 per cent, chlorantraniliprole - 0.03 per cent, indoxacarb - 0.10 per cent and chlorpyriphos - 0.05 per cent (as check) against the resistant population of M.vitrata revealed that the per cent mortality of the second instar larvae treated with insecticides viz. emamectin benzoate, indoxacarb+acetamiprid and spinosad were 97.28, 97.28 and 90.90 per cent respectively after 6 hours of treatment. Hence, these insecticides were selected for further field trials against the resistant population of M .vitrata. The field experiment was conducted in RBD with four treatments viz. emamectin benzoate 0.002 per cent, indoxacarb+acetamiprid 0.09 per cent and spinosad 0.015 per cent including control against the resistant population of M.vitrata. Application of emamectin benzoate, indoxacarb + acetamiprid and spinosad resulted in a reduction of 81-100, 64-100 and 69.96 - 99.6 per cent respectively in the case of flower infestation and 83 -100, 23.38 - 98.40 and 55.26 – 100 per cent respectively in case of pod infestation. Harvest time residue estimation done on 7th day after the application of insecticides showed the residues below the quantitative limit of 0.05 mg kg-1 revealing its safety for consumption. The study could indicate the development of insecticide resistance in the field population of M.vitrata. On the basis of the present study it could be concluded that spraying of emamectin benzoate @ 10 g ai ha-1 or indoxacarb + acetamiprid @100 g ai ha-1 or spinosad @ 75 g ai ha-1 could effectively manage the resistant population of M. vitrata in cowpea. This study forms a maiden attempt in assessing the extent of insecticide resistance development in the populations of M. vitrata in Kerala. Further studies have to be taken up to develop and popularize an Insecticide Resistance Management (IRM) strategy against this devastating pest of cowpea.
Open Access
Management of root-knot nematode, Meloidogyne sp. (Kofoid and White) in Coleus, Solenostemon rotundifolius(Poir) morton
(College of Horticulture, Vellanikkara, 2014) Lakshmy, K Mohan; KAU; Susannamma, Kurien
The study entitled ‘Management of root-knot nematode, Meloidogyne sp. in coleus, Solenostemon rotundifolius (Poir) Morton’ was conducted at College of Horticulture, Vellanikkara during 2012-2013 with the objectives of assessment of the population of plant parasitic nematodes infesting coleus at different coleus growing regions of Thrissur District, identification of the species of Meloidogyne infesting coleus and evaluation of biocontrol agents, organic amendments and a chemical insecticide against this root- knot nematode in coleus. Survey was conducted in the major coleus growing areas of Thrissur District, namely Mundathikode, Wadakkanchery, Varavoor, Thirur, Kolazhi, Vellanikkara, Madakkathara and Vadanapilly. Soil and tuber samples were collected from these localities and the nematodes were extracted to assess the population of plant parasitic nematodes associated with coleus. It was found that root-knot nematode was the major problem in all the eight locations and the species of root-knot nematode was identified as Meloidogyne incognita (Kofoid and White) Chitwood, 1949 on the basis of perineal pattern of white females. Other plant parasitic nematodes recorded from soil samples were reniform nematode (Rotylenchulus reniformis Linford and Oliveiria), burrowing nematode (Radopholus similis (Cobb, 1893) Thorne, 1949), lance nematode (Hoplolaimus sp.), spiral nematode (Helicotylenchus sp.) and rice-root nematode (Hirschmanniella oryzae Luc and Goodey, 1963) which were not harmful to the tubers of coleus. The highest average root-knot nematode population was recorded from Kolazhi with 450.4 nematodes/ 200g soil with a gall index of 3.9. Pot culture experiment was carried out to evaluate the efficacy of biocontrol agents, organic amendments and a chemical insecticide against root-knot nematode infesting coleus. The results showed that application of organic amendments namely whole plant of Tagetes erecta, leaves of Chromolaena odorata and neem cake resulted in the enhancement of plant growth characters and resulted in a reduction of root-knot nematode population. Incorporation of T. erecta whole plant ranked first among the organic amendments. Neem cake, cartap hydrochloride 4G and combination treatments of Bacillus subtilis + Pseudomonas fluorescens and P. fluorescens + Paecilomyces lilacinus improved the yield of coleus plants. Soil application of P. lilacinus, cartap hydrochloride 4G and incorporation of T. erecta suppressed the nematode population in soil, root and tuber respectively. Combination treatment of P. fluorescens + P. lilacinus and application of neem cake also reduced population buildup of nematode and kept the infestation at a lower level. Highest reduction in number of females, number of root knots and root knot index was also observed in T. erecta and was followed by P. lilacinus, P. fluorescens + P. lilacinus, neem cake and C. odorata. The study clearly indicated that application of organic amendments and biocontrol agents were found to be as effective as cartap hydrochloride 4G in managing the root-knot nematode population in coleus and can be considered as alternative to nematicide application.
Open Access
Entomopathogenic nematodes for the management of cashew stem and root borer, Plocaederus ferrugineus L. (Coleoptera; Cerambycidae)
(College of Horticulture, Vellanikkara, 2014) Deepak, S Poojari; KAU; Gavas, Rajesh
The study entitled “Entomopathogenic nematodes for the management of cashew stem and root borer, Plocaederus ferrugineus L. (Coleoptera: Cerambycidae)’’was conducted at the Cashew Research Station, Madakkathara, Kerala Agricultural University during 2013-14 in order to evaluate the possibility of utilization of five different species of entomopthogenic nematodes i.e., Heterorhabditis indica Poinar, H. bacteriophora Poinar, Steinernema carpocapsae (Weiser) Wouts, S. abbasi Elaward and S. bicornutum Tallosi, to control the cashew stem and root borer (CSRB) Plocaederus ferrugineus L. The objectives of the study were to identify the potent species of entomopathogenic nematode (EPN) and to determine the optimum inoculum levels needed to induce mortality, analyze the foraging behaviour of EPN species and to test the field efficacy of the selected EPN species against CSRB. The five species of entomopathogenic nematodes were tested each at three different inoculum levels against the grubs of CSRB in the laboratory. Third instar grubs of CSRB were introduced into petridishes lined with Whatman No.1 filter paper and were inoculated with different species of EPN at three different inoculum levels (100, 500 1000 IJs/ml of distilled water). The mortality of grubs was recorded up to 15 days of treatment. Complete mortality was observed in all the treatments except in case of grubs which were treated with S. abbasi and S. bicornutum at 100 IJs/ ml. Steinernema carpocapsae showed significant difference from other treatments at 1000 IJs/ ml and it was followed by H. bacteriophora. Though mortality of grubs was observed in all species of EPN at different inoculum levels, emergence of EPN was observed only from those grubs treated with H.bacteriophora and S. carpocapsae both at 1000 IJs/ml inoculum level. Based on the results of first experiment, out of the five EPN species, only S.carpocapsae and H.bacteriophora were selected for further studies on their foraging behaviour. Foraging behavior was tested using vertical plastic columns of 5.5 cm diameter and 30 cm length as per the method developed by Koppenhofer and Kaya (1998). Individual grub of CSRB was placed in a wire mesh cage at 0, 5, 10 and 20 cm depth in the plastic column and both ends were covered with Petridishes (60×15 mm). One ml of EPN suspension containing 1000 IJs was released from the top of the plastic columns and incubated for 120 hours. Heterorhabditis bacteriophora could penetrate up to a depth of 10 cm within a time of 120 hours, while S. carpocapsae could only infect the grubs which were placed on the surface. This indicates that H. bacteriophora has better foraging capacity as compared to S. carpocapsae. Based on the results of laboratory experiment, H. bacteriophora was selected for evaluating its field efficacy against CSRB. Application of H. bacteriophora was done by using three methods, viz., drenching the soil with EPN suspension, placing EPN impregnated sponges in bore holes and placing EPN infected wax moth cadavers in the bore holes. Chemical treatment was also done by using chlorpyriphos 20 EC @ 0.2 per cent (KAU POP, 2011). Live grubs were observed in all treatments after one month of treatment application. Chlorpyriphos has performed better compared to the EPN treatments.
Open Access
Population dynamics and management of coconut root grub (Leucopholis coneophora burm.)
(College of Agriculture, Padannakkad, 2014) Jeevan, C H; KAU; Sreekumar, K M
The population dynamics and management of coconut root grub (Leucopholis coneophora Burmister) was studied in the laboratory and field of College of Agriculture, Padnekkad, Kasaragod, Kerala during 2013-14. In the study on efficiency of light traps in collecting the adult beetles, the mercury light trap has recorded the prolonged collection, highest number of beetles and female beetles followed by ultraviolet trap and black light trap. The daily maximum and minimum temperature and soil temperature negatively and rainfall positively correlated with adult emergence. Larval population has shown a decreasing trend from August to February and highest larval population per coconut basin was 29.96. Laboratory plastic cup experiments, field pot experiments and field cage experiments were conducted to develop management measures. In the plastic cup studies, 100 per cent mortality was observed in the treatments with Novaluron, Clothianidin, Azadirachtin 1500 ppm @ 5ml/L, 10ml/L, 15ml/L and Malathion which are on par with CNSL 2% (80) and Chlorpyrifos (66). In the pot studies, maximum mortality of 98 per cent was observed in treatments with Azadirachtin 10ml/L and 15ml/L followed by Malathion with 97 per cent and Clothianidin with 87 per cent which are significantly better. In the cage studies, the treatment viz. Azadirachtin 15ml/L gave highest mortality (97 per cent) followed by Malathion (87), Clothianidin (73), Azadirachtin10ml/L (70) and Azadirachtin 5ml/L (63). There was no mortality in absolute control. The EPN Heterorhabditis indica inflicted no mortality. In no-choice test conducted to study the repellency of botanicals to root grub larva, significantly highest repellency was observed in cashew nut shell liquid (CNSL) 2 % followed by Azadirachtin concentrations.

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