EFFECT OF DIFFERENT CHEMICAL PESTICIDES ON MUSTARD APHID (LIPAPHIS ERYSIMI) AND THEIR ADVERSE EFFECTS ON LADYBIRD BEETLE

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1 Sarhad J. Agric. Vol.27, No.4, 2011 EFFECT OF DIFFERENT CHEMICAL PESTICIDES ON MUSTARD APHID (LIPAPHIS ERYSIMI) AND THEIR ADVERSE EFFECTS ON LADYBIRD BEETLE KAMRAN SOHAIL*, SALIM JAN*, SYED FAHAD SHAH*, HUSSAIN ALI**, MUHAMMAD ISRAR***, MUHAMMAD FAROOQ****, SAAD JAN*, MUHAMMAD ARIF***** and BASHIR AHMAD****** * Department of Entomology, Agricultural University, Peshawar Pakistan. ** Entomology Section, Agricultural Research Institute, Tarnab, Peshawar Pakistan. *** Department of Developmental Studies, University of Swat, Swat Pakistan. **** Department of Management Sciences, Abasyn University, Peshawar Pakistan. ***** Institute of Business and Management Sciences, Agricultural University, Peshawar Pakistan. ****** Department of Plant Protection, Agricultural University Peshawar Pakistan. sohailagrian@yahoo.com ABSTRACT The present research was carried out at Agricultural Research Institute, Tarnab, Peshawar, Pakistan during 2008 to study the effect of different chemical pesticides on mustard aphid (L. erysimi) and their adverse effects on Ladybird beetle in Turnip field. The experiments were carried out with eight treatments, Actara 5g/100 lit water, Actara 10g/100 lit water, Actara 15g/100 lit water, Confidor 80ml/100ml lit water, Confidor lit water, Confidor 120ml/100 lit water, 200ml/100 liter of water with a control. Results showed that Fastkil was more toxic to the mustard aphid (L. erysimi) population followed by Actara (high), Actara (medium) and Actare (low), respectively. Fastkil was found most lethal for the ladybird beetle population followed by Confidor (high), Actara (low), Confidor (low), Confidor (medium), and Actara (medium) respectively. The study recommends the use of Actara for the safe and effective control of mustard aphid (L. erysimi). Farmers should use Actara for the control of Aphids (L. erysimi) in the field as it is the least toxic to ladybird beetle population. Key Words: L. erysimi, chemical pesticides, adverse effects, ladybird beetle, turnip. Citation: Sohial, K., S. Jan, S.F. Shah, H. Ali, M. Israr, M. Farooq, S. Jan, M. Arif and B. Ahmad Effect of different chemical pesticides on mustard aphid (Lipaphis Erysimi) and their adverse effects on ladybird beetle. Sarhad J. Agric. 27(4): INTRODUCTION Turnip (Brassica rapa L) is one of the most important dicotyledonous, cross pollinated and cool season cruciferous root vegetable crops. It is native to Northern Asia and extensively grown in Europe, Asia and United States (Kamal, 1997). Cruciferous crops are attacked by many insect pests. The mustard aphid, Lipaphis erysimi (Kaltenback) (Hemiptera: Aphididae) is one of the serious pests of cruciferous crops (Rouf and Kabir, 1997) and is distributed in many countries of the world (Setokuchi, 1983). The damage is caused by both nymphs and the adults, these are louse-like and pale greenish insects, are seen feeding in large numbers, often covering the entire surface of the flower buds, shoots, pods etc (Ahmed and Jalil, 1993). Among the naturals enemies coccinellids are the best known beneficial predatory insects. Coccinellids are commonly known as ladybird, lady beetles or lady bugs. Lady bird belongs to the family Coccinellidae and order Coleoptera. About 6000 species of ladybird beetles found all over the world (Vandenberg, 2000), out of which 71 predatory ladybird beetles belongs to Pakistan (Irshad, 2001). Ladybird beetles are generally considered useful insects as many species feed on soft bodied insects like aphids, jassids, psyllids, whiteflies, scale insects, mealy bugs, insect eggs, small larvae and phytophagus mites which are injurious to agricultural crops and forest plantations (Rafi et al., 2005). Some of the ladybird beetles are susceptible to chemical insecticides chlorpyrifos and pirmicarb at the recommended rates. Generally, the 1 st and 2 nd instars of ladybird beetles were very sensitive to thiamethoxam and abamectin but these chemicals are very effective against aphids. (Youn et al., 2003).

2 Kamran Sohail et al. Effect of different chemical pesticides on mustard aphid 612 Some of the insecticides are fast killing all the life stages of coccinellids that feed on the treated aphids. Carbaryl and phosmet are slow acting insecticides that cause the greatest mortility. Methomyl did not cause 100% mortality of ladybird beetle feeding on insecticides treated aphids (Hurej and Dutcher, 1994). The present study aimed to determine the effect of different chemical pesticides on L. erysimi and their adverse effects against ladybird beetle. MATERIALS AND METHODS To study the effects of different chemicals on mustard aphid (L. erysimi) and their adverse effects on ladybird beetle, an experiment was laid out in the turnip field at Agricultural Research Institute, Tarnab, Peshawar during Plot size for turnip was 15m X 3.75m, plant to plant distance was 0.30-m and row to row distance measured 0.75-m. The following chemicals were sprayed with their respective concentrations. Chemical Chemical Group Rate/100 lit water Confidor (20SL) (Imidacloprid) ml Confidor (20SL) ml Confidor (20SL) ml Actara (25WG) (Thiamethoxam) 5.00g Actara (25WG) g Actara (25WG) g Fastkil (Methomyl) ml Control (Untreated) - The experiment was replicated three times in Randomized Complete Block Design. Data on population density of aphids and ladybird beetle were collected on the alternate days after spray till ninth day at two days interval. Population Density of Aphid Population density of aphid was recorded on linear colony dimension after spray. Data were collected from three different strata of plant i.e. top, middle and lower parts of five randomly selected turnip plants. The column length of aphid colony was scaled and the number of aphids was counted in the colony. Population density of aphid/cm 2 were determined by the following formula. Population density of aphid/cm 2 = From the above data the mean aphid density was calculated. Population Density of Ladybird Beetle Number of aphid in colony Column length of colony Number of ladybird beetles was counted in five randomly selected turnip plants for each treatment and mean population density was determined. Data was analyzed statistically and evaluated through LSD test (Steel and Torrie, 1980). RESULTS AND DISCUSSION Effect of Chemicals on L. erysimi Data collected after one day of spraying indicated that the lowest population of aphid was recorded on Confidor (low) and medium i.e. recording 3.46 and 5.60 aphids/cm 2, followed by Confidor (high), was at Actara (high), Actara (medium) and Fastkil. The aphid population (14.10 aphids/cm 2 ) on Actara (low) on par with control, which recorded an aphid population of aphid/cm 2. The aphid population after one day of spraying of Fastkil, Confidor (high), Confidor (medium), Confidor (low) Actara (high) and Actara (medium) were significantly different from Actara (low) and control Table I. Data recorded three days after spraying revealed the lowest population of aphids on Fastkil and Confidor (medium) i.e and 2.93 aphids/cm 2 as compared to the control where the population density

3 Sarhad J. Agric. Vol.27, No.4, of aphids was Data further revealed the highest population density of aphids on Confidor (low) (6.06 aphids/cm 2 ) and Actara (low) (7.43 aphids/cm 2 ). The aphid population (3.60 aphids/cm 2 ) on Actara (medium) on par with Confidor (medium) and Actara (high). Confidor (medium), Confidor (high), Actara (medium), Actara (high) and Fastkil were significantly different from Confidor (low), Actara (low) and control. Data recorded after five, seven, nine, twelve, fifteen, eighteen, twenty one and twenty four days were non-significant (Table I). Over all mean of the data indicated a significant difference among the treatments and control. The lowest population of 6.43 aphids/cm 2 was recorded on Fastkil which was followed by Confidor (high), Confidor (medium) and Actara (high) i.e. 7.09, 7.48 and 7.56 aphids/cm 2, respectively. The highest population density of aphids was recorded in control (14.42 aphids/cm 2 ). The population density of aphids recorded on Confidor (low), Actara (medium) and Actara (low) were 8.23, 9.21 and aphids/cm 2, respectively (Table I). These results coincide with the findings of Youn et al. (2003) who concluded that Thiamethoxam was effective in controlling L. erysimi population. These results also coincide with Khan and Begum (2000) and Sultana et al., (2009) who stated that Thiodan and Actara are efficient in reducing aphid s population. Ahmad et al. (2007) found that synthetic insecticide highly reduced mustard aphid population. Effect of Chemicals on Ladybird Beetle Observation recorded nine days after spraying indicated lowest population density of ladybird beetle on Fastkil and Actara (high) i.e and 1.00/5 plants followed by Confidor (medium) i.e ladybird beetle/5 plants. The aphid population (3.00) recorded on Confidor (high) on par with Actara (low) and Actara (medium). A highest population density (5.00 ladybird beetle/5 plants) was recorded in control. All the treatments were significantly different with the control Table II. Data recorded twelve days after spraying revealed the lowest population on Fastkil i.e ladybird beetle/5 plants which was followed by Confidor (high) (2.33 ladybird beetle/5 plants) and Actara (low) (4.00 ladybird beetle/5 plants). Data also revealed ladybird beetle/5 plants on Actara (medium) which is at par with Actara (high) and Confidor (medium). The highest population of ladybird beetle/5 plants was recorded in control (14.00) (Table II). Data in Table II fifteen days after spraying indicated the lowest population of 2.00 ladybird beetle/5 plants on Actara (medium) which was at par with all the treatments as compared to the control where the highest number of ladybird beetle/5 plants was recorded i.e All the treatments were significantly different from control. No significant difference was recorded in all the treatment after eighteen, twenty one and twenty four days after spraying (Table II). Results concluded from overall mean showed the lowest population of 2.16 ladybird beetle/5 plants on Fastkil as compared to the control where the highest number of 9.56 ladybird beetles/5 plants was recorded. The ladybird beetle population (4.33) on Confidor (low) was at par with Confidor (medium) and Actara (medium). The population of ladybird beetle recorded on Confidor (high), Actara (low), and Actara (high) were 3.29, 3.66 and 4.76 ladybird beetles/5 plants, respectively (Table II). Data recorded one, three, five and seven days after spraying indicated non significant differences among the treatments and control, however significant difference was recorded after nine, twelve and fifteen days after spraying. This significant difference might have been due to either increase in prey availability (Agarwalam and Bardhanroy, 1999) or due to abundance of floral resources as reported for Harmonia axyridis (Lundgren et al., 2004). Fastkil (Methomyl) turned out to be the most lethal insecticide for ladybird beetle. Our results are contrary to the findings of Hurej and Dutcher (1994) and Liu-Aizhi et al. (1996) who concluded that Methomyl and Imidacloprid were relatively less toxic to ladybird beetles. These findings are similar to the findings of Youn et al. (2003) who stated that Thiamethoxam was very effective against aphids but highly toxic to ladybird beetle population. James (2003) found that Thiamethoxam was the least toxic Harrmonia axyridis population in laboratory bioassays.

4 Kamran Sohail et al. Effect of different chemical pesticides on mustard aphid 614 Table I Population density of R. erysimi following spray of the insecticides in Turnip field Mean density/sq cm in days Treatments Rate (a.i) Days 100 lit H 2O Mean Confidor (low) 80ml 3.46 d 6.06 ab d Confidor (medium) 100ml 5.60 d 3.26 bc e Confidor (high) 120ml 7.06 cd 2.93 c f Actara (low) 5gm ab 7.43 a b Actara (medium) 10gm bc 3.60 bc c Actara (high) 15gm 6.60 cd 3.4 bc e Fastkil 200ml 8.20 cd 2.33 c g Control a 8.60 a a LSD Value Note: Within a column means followed by different letters are significantly different at 0.05 probability level. Table II Population density of Ladybird beetle following spray of the insecticides in Turnip field Mean density/5 plants in days Treatments Rate (a.i) 100 Days lit H 2O Mean Confidor (low) 80ml ab 4.00 bcd 5.00 b C Confidor (medium) 100ml b ab 4.66 b C Confidor (high) 120ml ab 2.33 cd 3.66 b E Actara (low) 5gm ab 4.00 bcd 2.00 b D Actara (medium) 10gm ab abc 2.00 b C Actara (high) 15gm b ab 2.33 b B Fastkil 200ml b 0.33 d 2.66 b F Control a a a A LSD Value Note: Within a column means followed by different letters are significantly different at 0.05 probability level.

5 Sarhad J. Agric. Vol.27, No.4, CONCLUSION AND RECOMMENDATIONS The lowest population of L. erysimi was recorded in Fastkil (methomyl) and Confidor (Imidacloprid) where as highest population of aphids was found on Actara (Thiamethoxam). The highest population of ladybird beetle was recorded in Actara. The population of ladybird beetle was the lowest and turned out to be more toxic for natural enemies. On the basis of study findings the following recommendations are made: i. Due to less toxic effects against ladybird beetle Actara should be used for the effective control of R. erysimi. ii. Farmers should use Actara for the control of Aphids (R. erysimi) in the field. REFERENCES Agarwalam, B.K. and P. Bardhanroy Numerical response of ladybird beetles (Coleoptera: Coccinellidae) to aphid prey (Hom: Aphididae) in a field bean in northeast India. J. Appld. Entomol. 123: Ahmed, T.U. and A.F.M.A. Jalil Bangladesher Krishir Onistokari Pokamakor, Jiban Brittanta O Nyantron (Bangla). Bangladesh Acad. Dhaka. 381p. Hurej, R.M. and D.T. Dutcher The toxicity of response from insecticides with an ethyl fatty ester-based adjuvant. Pest and Diseases. Proc. Int l. Conf. Brighton, U.K. 4: Irshad, M Distribution, hosts, ecology and biotic potential of Coccinellids of Pakistan. Pak. J. Biologic. Sci. 4: James, D.G Pesticide susceptibility of two Coccinellids (Stethorus punctum picipes and Harmonia axyridis) important in biological control of mites and aphids in Washington Hops. Biol. Sci. Tech.13(2): Kamal, M The effect of N, P and K on growth and yield of turnip. M.Sc (Hons) Thesis, Agric. Univ. Peshawar, Pakistan. 50p. Liu-Aizhi, J. Choi, B. Yu, T. Jeong, J.K. Choi, B.J. Yu and T.S. Jeong Controlling Macrosiphum avenae and Rhopalosiphum padi with four insecticides in wheat crop. RDA J. Agric. Sci. Crop Prot. 19: Lundgren, J.G., A.A. Razzak and R.S. Wiedennmann, R.S. 2004: Populationand food consumption by predators Coleomegilla maculata and Harmonia axyridis (Coleoptera: Coccinellidae) during anthesis in an Illinois cornfield. Envir. Entomol. 33: Rafi, M.A., M. Irshad and M. Inayatullah Predatory Ladybird beetles of Pakistan. National Insect Museum & Insect Pest Informatics. Rouf, F.M.A. and K.H. Kabir Economic efficacy of some insecticides for the control of mustard aphid, L. erysimi Kalt. Bangladesh J. Entomol. 7 (1 & 2): 1-7. Setokuchi, O Seasonal prevalence of Myzus persicae Sulzer. and L. etysimi Kalt. (Homoptera: Aphididae) Kagoshima prefecture. Japan. J. Appld. Entomol. Zool. 21: Steel, R.G.D. and J.H. Torrie Principals and procedures of statistics. A biological approach. 2 nd ed. McGraw Hill Book. Co. New York. 481p. Vandenberg, N.J Coccinellidae Latreille pp. In: Arnett, R.H. Jr., M.C. Thomas, and P.E. Skelley. (eds). American Beetles V. 2. Polyphaga: Scarbaeoidae through Curculionidea CRC Press LLC, Boca Raton, FL. XIV+861 p. Ye-QiMing, P. Gao, T. Hou, R. Gao, Q. Cui, S. Liu, P. Gao, T.P. Hou, R. Gao, Q. Cui and S.G. Liu Efficacy of insecticides against aphids and natural enemies in cotton field and in laboratory. Pest Mgt. Sci. 3(16): Youn, Y.N., M.J. Seo, J.G. Shin, C. Jang and Y.M. Yu Toxicity of greenhouse pesticides to multicolored Asian lady beetles, Harmonia axyridis (Coleoptera: Coccinellidae). Biol. Cont. 28(2):