INTEGRATION OF TOLERANCE OF BT COTTON VARIETIES WITH INSECTICIDES AGAINST SPOTTED BOLLWORM, EARIAS INSULANA

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1 Sarhad J. Agric. Vol.28, No.1, 2012 INTEGRATION OF TOLERANCE OF BT COTTON VARIETIES WITH INSECTICIDES AGAINST SPOTTED BOLLWORM, EARIAS INSULANA (BOISD.) AND E. VITTELLA (FAB.) (NOCTUIDAE: LEPIDOPTERA) SAID MIR KHAN*, IMRAN SAEED*, MAHMOOD SHAH**, SYED FAHAD SHAH*** and HINA MIR**** * Department of Entomology, Faculty of Agriculture, Gomal University, Dera Ismail Khan Pakistan. ** Department of Economics, Faculty of Agriculture, Gomal University, Dera Ismail Khan Pakistan. *** Department of Entomology, Agricultural University Peshawar Pakistan. **** Department of Biochemistry, Faculty of Plant Sciences, Quaid I Azam University, Islamabad Pakistan. saidmirkhan@yahoo.com ABSTRACT To study the comparative efficacy of the insecticides viz., bifenthrin (Talstar 10 EC), spinosad (Tracer 240 SC), lambda cyhalothirn (Karate 2.5 EC), flubendiamide (Belt 480 SC) and spinothelin (Radiant 125 SC) on four cultivars of cotton were evaluated against spotted bollworm and integrated with the host plant resistance of BT cotton cultivars. These insecticides were sprayed twice i.e. on August 6 and September 4, The cotton varieties Bt-101, CIM-496, Bt-121, and MNH-786 were sown following two factors split plot protocol in Randomized Complete Block Design replicated three times in the experimental field of Cotton Research Centre, Sahiwal during Spinothelin was found highly effective against spotted bollworm followed by Spinosad. Bt cottons showed more resistance as compared to non-bt varieties. The variety Bt-101 showed minimum infestation level of squares, flowers and bolls followed by Bt-121. Key Words: Bt cotton, genetic resistance, chemical control, insecticides, IPM. Citation: Khan, S.M., I. Saeed, M. Shah, S. F. Shah and H. Mir Integration of tolerance of bt cotton varieties with insecticides against spotted bollworm, earias insulana (BOISD) and e. vittella (FAB) (noctuidae: lepidoptera). Sarhad J. Agric. 28(1): INTRODUCTION Cotton not only meets the needs of fiber of the local industry but also provides food in the form of edible oil and feed in the form of seed cake. It is the main source of foreign exchange earnings and brings about 60% of the foreign exchange annually from the export of raw material as well as its finished products (Govt. of Pakistan, 2008). Cotton crop production is on the verge of decline for the past few years. The low cotton yield has been attributed to many factors among which insects and mites are the major ones. As many as 93 insects and mites have been reported to attack the crop in Pakistan (Yunus and Yousuf, 1979), which on average cause 5-10 percent damage to cotton crop every year. These losses could be up to the extent of 54% (Chaudhary, 1976). American bollworm, Helicoverpa armigera (Hub.), spotted bollworm, Earias insulana (Boisd.) and E. vittella (Fab.) are important pests of cotton crop. Bollworms mainly feed on fruiting parts of cotton resulting in considerable losses both in quality and quantity (Ahmad, 1980). Spotted bollworms (Earias vittella and E. insulana) are serious pests of cotton and take a heavy toll from germination to maturity of the crop and in certain years cause 19-20% yield losses (Kamaluddin, 1994). Spotted bollworm attack on cotton crop at early stage causes top boring. The larva enters into the bolls and eats all its contents (Bariola and Lingern, 1984). Varietal resistance and chemical control has been mostly relied upon for the control of spotted bollworm on cotton (Wahla et al., 1998). In 2005, the PAEC provided 40,000 kg of Bt cotton seed varieties IR-FH-901, IR- NIBGE-2, IR-CIM-448, IR-CIM-443 which have been grown over 8000 acres of land (Rao, 2007). Bacillus thuringiensis (Berliner) is a soil bacterium that produces a diversity of Cry proteins that are toxic against a wide variety of insect pests (Crickmore et al., 1998). Bt cotton was commercially released in the United States in 1996 and subsequently in several countries including Argentina, Australia, China, Colombia, Indonesia, Mexico, South Africa and India (Shelton et al., 2002). Bt cotton has become an important tool for integrated pest management (IPM) especially for the lepidopterous larvae in cotton (Torres and Ruberson, 2005). To overcome the losses and to increase the yield, pesticides application is very important. In Pakistan, about 70-80% of pesticides were sprayed for controlling the cotton pests (Mohyuddin et al., 1997), while during , about tons of pesticides were imported (Malik, 2001). Use of insecticides for the control of cotton

2 Said Mir Khan et al. Integration of tolerance of Cotton verities with insecticides against bollworm 58 boll worms have been well documented (Talpur et al.,1993; Ravi et al.,1997; Sherma et al.,1997; Akber and Hassan, 1999; Naveed et al., 1999; Allen et al., 2000). In this project, the efficacy of insecticides viz., bifenthrin (Talstar 10 EC), spinosad (Tracer 240 SC), lambda cyhalothirn (Karate 2.5 EC), flubendiamide (Belt 480 SC) and spinothelin (Radiant 125 SC) were evaluated against spotted bollworm as integrated with the host plant resistance of Bt cotton cultivars. MATERIALS AND METHODS The studies were conducted on sustainable management of spotted bollworm on different varieties of cotton by different insecticides at Cotton Research Centre, Sahiwal during Sowing of Cotton The seed of the varieties under trial viz. Bt-101, CIM-498, Bt-121 and MNH-786, were obtained from the local market. The present investigation was undertaken to evaluate the performance of Bt cotton varieties (Bt-101, Bt-121) against the conventional cotton varieties (CIM-496, MNH-786) for spotted bollworms under insecticidal management. The experiment was laid in two factors split plot in Randomized Complete Block Design. Varieties were assigned to the mainplots while, insecticides were kept in the sub-plots. Each sub-plot size was 3 7m 2. All the recommended agronomic practices were followed for the sowing of crop. Selection of Insecticides Insecticides viz., bifenthrin (Talstar 10 EC) spinosad (Tracer 240 SC), lambda cyhalothirn (Karate 2.5 EC), flubendiamide (Belt 480 SC) and spinothelin (Radiant 125 SC) were selected and obtained from the respective companies. Recommended field doses (625, 100, 715, 125 and 100 ml ha -1, respectively) were sprayed. Insecticide Application Schedule The application of insecticides was begun when pest infestation/population crossed a defined threshold level (3 adults per 25 plants). The concentrations of the selected insecticides were prepared according to the field recommendations. The insecticides were sprayed twice on the crop with the help of a backpack knapsack sprayer having a hollow cone Nozzle at fortnightly intervals. Collection of Data The data were recorded before application and 1, 3, 7 and 15 days after each spray. Data were collected from bolls, squares and flowers from five plants per plot by random selection. The percentage infestation was noted by using the formula. Data Analysis % Infestation = Infected bolls X 100 Total bolls The data were analyzed by using Fisher s analysis of variance techniques (Steel et al., 1997). The treatment means were separated using Least Significant Difference Test. RESULTS AND DISCUSSION The data (Table I) regarding spotted bollworm infestation on cotton flowers/squares/bolls, after one day of first and second spray application of insecticides showed that the effect of treatments on spotted bollworm was significantly different as compared to control. The lowest mean infestation of 0.27% and 1.25% was recorded in the plots after one day of first and second spray of Spinothelin, respectively. The results revealed that Bt varieties of cotton also played significant role in the bollworm infestation on squares. The data showed that the highest mean infestation of 1.57% and 2.85% was recorded in variety MNH-786 after one day of first and second spray of insecticides, which differed significantly from the remaining varieties. The lowest mean infestation of 0.91% and 1.38% was recorded in variety Bt-101. It was further noted that the effect of varieties and treatments on spotted bollworm was highly significant. Spinothelin gave good results on all the varieties with minimum infestation level of 0.18% and 0.27% of squares in Bt-101.The highest infestation of squares was noted in MNH-786 with infestation level of 1.57% and 2.85% after one day of first and second spray treatment, respectively.

3 Sarhad J. Agric. Vol.28, No.1, The data regarding performance of cotton varieties on spotted bollworm infestation of flowers/squares/bolls after 3 days of first and second application of insecticides (Table II), showed that all varieties were found significantly different after first spray, while non-significantly different after second spay of insecticides except in variety Bt-121. The data further showed that the highest mean infestation of 3.24% was recorded in CIM-496, which differed significantly from the remaining varieties. The lowest mean infestation recorded in variety Bt-121 was statistically at par with Bt-101. Table I Percent infestation of cotton flowers, squares and bolls after one day of first and second spray of insecticides BT-101 CIM-496 BT-121 MNH-786 Ist Spray 1.80 cd 3.00 b 2.27 c 4.30 a 2.84 a 2 nd Sray 1.58 cde 5.15 a 1.94 bcd 4.87 a 3.38 a Ist Spray 1.03 defghij 1.50 cdef 1.25 defgh 1.42 def 1.30 bc 2 nd Sray 1.78 bcde 2.75 bc 1.40 cde 2.83 bc 2.19 b Ist Spray 0.50 ghij 1.06defghi 0.67 fghij 0.72 efghij 0.74 d 2 nd Sray 1.48 cde 2.33 bc 1.49 cde 1.88 bcde 1.80 bc Ist Spray 1.27 defgh 1.50 cdef 1.35 defg 1.57 cde 1.42 b 2 nd Sray 1.43 cde 3.24 b 1.95 bcd 2.87 bc 2.37 b Ist Spray 0.70 efghij 1.23 efgh 0.88 efghij 1.00 efghij 0.95 cd 2 nd Sray 1.73 bcde 2.33 bc 1.46 cde 2.23 bc 1.94 bc Ist Spray 0.18 j 0.20 ij 0.27 ij 0.43 hij 0.27 e 2 nd Sray 0.27 e 1.76 bcde 0.55 de 2.41 bc 1.25 c Ist Spray 0.91 c 1.42 ab 1.11 bc 1.57 a 2 nd Sray 1.38 b 2.93 a 1.46 b 2.85 a LSD 0.05 value (insecticides) for Ist Spray = 0.37, 2 nd Spray =0.68 LSD 0.05 value (varieties) for Ist Spray = 0.43, 2 nd Spray= 0.56 LSD 0.05 value (varieties x insecticides) for Ist Spray = 0.73, 2 nd Spray=1.36 s sharing the similar letters do not differ significantly in respective sprays at P= Table II Percent infestation of cotton flowers, squares and bolls after three days of first and second spray of insecticides BT-101 CIM-496 BT-121 MNH-786 Ist Spray 1.90 hijk 5.55 a 2.00 ghijk 4.55 b 3.50 a 2 nd Spray 4.52 b 7.50 a 3.26 cd 7.58 a 5.72 a Ist Spray 2.37 efghi 3.08 de 1.92 hijk 2.82 efg 2.55 b 2 nd Spray 3.28 cd 3.29 cd 2.72 cdef 2.88 cde 3.04 bc Ist Spray 1.00 lm 2.23 fghij 1.02 lm 1.75 hijkl 1.50 d 2 nd Spray 2.21 defg 1.60 ghi 1.40 ghi 1.95 efgh 1.79 d Ist Spray 2.43 efgh 4.33 bc 2.37 efghi 3.78 cd 3.22 a 2 nd Sray 3.72 bc 3.51 bc 2.24 defg 3.52 bc 3.25 b Ist Spray 1.48 jkl 2.88 ef 1.56 ijkl 2.22 fghijk 2.04 c 2 nd Spray 2.89 cde 2.25 defg 3.25 cd 2.32 defg 2.68 c Ist Spray 0.60 m 1.38 kl 0.52 m 1.47 jkl 0.99 e 2 nd Sray 2.89 cde 2.25 defg 3.25 cd 2.32 defg 2.68 c Ist Spray 1.63 b 3.24 a 1.56 b 2.76a 2 nd Sray 2.99 a 3.17 a 2.24 b 3.18 a LSD 0.05 value (insecticides) for Ist Spray = 0.36, 2 nd Spray =0.499 LSD 0.05 value (varieties) for Ist Spray =0.70, 2 nd Spray= 0.41 LSD 0.05 value (varieties x insecticides) for Ist Spray = 0.72, 2 nd Spray=0.997 s sharing the similar letters in the respective spray do not differ significantly at P= 0.05 The interaction of varieties and treatments showed significantly different effect on spotted bollworm infestation. Spinothelin gave good results on all the varieties with minimum infestation of squares in Bt-101 followed by Bt-121. The highest infestation of squares was deciphered in MNH-786 and CIM-496. The results recorded after seven days of first and second spray of insecticides on spotted bollworm infestation (Table III), showed significantly different effect of treatments. Data revealed the highest mean infestation as recorded in the control plots, which differed significantly from all insecticidal applications. The lowest mean infestation of 1.29% was noted in the plots treated with Spinothelin, followed by Spinosad.

4 Said Mir Khan et al. Integration of tolerance of Cotton verities with insecticides against bollworm 60 The tested cotton varieties played significant role in resistance/tolerance to spotted bollworm infestation, as the data recorded after seven days of first and second application of insecticides (Table III) showed that the highest mean infestation was recorded in variety CIM-496 and in MNH-786, which differed significantly from the remaining varieties. The lowest mean infestation was recorded variety Bt-101 and Bt-121. Table III Percent spotted bollworm infestation of cotton flowers, squares and bolls after seven days of first and second spray of insecticides. BT-101 CIM-496 BT-121 MNH-786 Ist Spray 3.02 defg 5.58 a 3.00 defg 4.55 b 4.04 a 2 nd Spray 4.50 cd 9.41 b 5.43 c a 8.32 a Ist Spray 2.15 fghij 3.33 cde 2.62 efghi 3.25def 2.84 bc 2 nd Spray 3.33 defg 3.05 efghi 2.84 efghi 3.56 def 3.20 b Ist Spray 1.68 hijk 1.88 ghijk 1.47 ijk 2.33 efghi 1.84 d 2 nd Spray 2.16 ghijk 1.98 ijk 2.04 hijk 2.33 fghijk 2.13 d Ist Spray 2.59 efghi 4.33 bc 2.37 efghi 3.83 bcd 3.28 b 2 nd Spray 3.80 de 3.55 def 3.24 efgh 3.65 de 3.56 b Ist Spray 2.09 ghij 2.73 defgh 2.35 efghi 2.92 defg 2.52 c 2 nd Spray 2.72 efghi 2.59 efghij 2.60 efghij 2.73 efghi 2.66 c Ist Spray 0.92 k 1.50 ijk 1.03 jk 1.72 hijk 1.29 e 2 nd Spray 1.46 jk 1.91 ijk jk 2.27 fghk 1.40 e Ist Spray 2.07 b 3.23 a 2.14 b 3.10 a 2 nd Spray c 3.66 b 2.94 c 4.58 a LSD 0.05 value (insecticides) for Ist Spray = 0.48, 2 nd Spray =0.53 LSD 0.05 value (varieties) for Ist Spray =0.32, 2 nd Spray= 0.43 LSD 0.05 value (varieties x ireatments) for Ist Spray =0.97, 2 nd Spray= 1.06 s sharing the similar letters in the respective sprays do not differ significantly at P= 0.05 The interactive effect of varieties and treatments on spotted bollworm infestation was statistically significant after seven days of first and second application of insecticides. Spinothelin gave good results on all the varieties with minimum infestation of squares in Bt-101 followed by Bt-121. The highest infestation of squares was noted in MNH-786 and CIM-496. Lambda cyhalotherin showed minimum infestation compared to other insecticides. Results obtained after 15 days of first and second application of insecticides for control of spotted bollworm infestation on flowers/squares/bolls are given in Table IV. The data showed that all tested insecticides were found significantly effective against spotted bollworms compared to control. The results further revealed that the highest mean infestation of 7.09% and 8.46% was noted in the untreated () plots, which differed significantly from the remaining treatments. The lowest mean infestation of 2.38% and 1.51% was noted in the plots treated with Spinothelin, which was at par with Spinosad. The effectiveness of varieties against spotted bollworm was also found significantly different from each other. The data showed that the highest mean infestation was recorded in MNH-786, which differed significantly from the remaining varieties. The lowest mean infestation was reported in the plots of Bt-101, followed by Bt-121. The data revealed significant interactive effect between varieties and insecticides on spotted bollworm infestation. Spinothelin gave good results on all the varieties with minimum infestation of squares and flowers in Bt-121 followed by variety Bt-101.The highest infestation of squares and flowers was noted in CIM-496 and MNH-786. The main objective was to find out the efficacy of five tested insecticides (viz., Bifenthrin (Talstar 10 EC), Spinosad (Tracer 240 SC), Lambda cyhalothirn (Karate2.5 EC) Flubendiamide (Belt 480 SC) and Spinothelin (Radiant 125 SC) at their recommended doses), being used at present for the control of spotted. Boll worm and integrated with host plant resistance of Bt cotton cultivars. It is clear from the results that Spinothelin gave best results than all other treatments followed by Spinosad, Flubendiamide, Bifenthrin and Lambda Cyhalothrin These findings are similar to the findings of Aslam et al. (2004), Gupta et al. (2005), Raguraman and Uthamasamy (2005) and Basavaraj and Gupta (2006) who reported that Spinosad gave good results against spotted bollworm. The data show the effective control of spotted bollworm compared to control. Spinothelin was found highly effective against spotted bollworm followed by Spinosad. The treatments Flubendiamide, Bifenthrin and Lambda Cyhalothrin also proved effective against spotted bollworm. The present finding cannot be compared with those of Mushtaq et al. (2001) and Anonymous ( )

5 Sarhad J. Agric. Vol.28, No.1, The results revealed that minimum infestation level of squares, flowers and bolls were noted on variety Bt- 101, at all the intervals of observation which is statistically at par with Bt-121. Maximum infestation level of squares, flowers and bolls were recorded on variety MNH-786 at all the intervals of observation followed by CIM The present findings fully agreed with Moser et al. (2000), Abro et al. (2004) and Sharma and Pampapathy (2006). Sarfraz et al. (2005) studied the resistance of transgenic (IRFH-109, IRCIM-443 and IRCIM-448) and conventional cotton cultivars (NIAB-Karishma, CIM-109, CIM-446, CIM-473 and FH-900) to bollworms (spotted bollworm; pink bollworm; American bollworm) and stated that the overall infestation was the highest on FH-900, indicating that this is the most susceptible genotype. IRFH-901, IRCIM-443 and IRCIM-448 were the most resistant to bollworm infestation. These results agree with our present study that the Bt-101 and BT-121 showed maximum resistance to spotted bollworm attack than non-bt varieties. The present findings fully agreed with Bricle et al. (1999) who determined the efficacy of six insecticides against the cotton bollworm and transgenic Bacillus thuringiensis. Moreover, the present findings are also similar to those of Moser et al. (2000), who evaluated the performance of transgenic cotton varieties under Arizona conditions. Four field tests were conducted at Arizona locations in 1999 using total no of 34 varieties in one or more tests. Transgenic cotton proved resistant to bollworms and provided 7 to 8 percent more lint yield than conventional varieties. Table IV Percent spotted bollworm infestation of cotton flowers, squares and bolls after fifteen days of first and second spray of insecticides BT-101 CIM-496 BT-121 MNH-786 Ist Spray 4.58 cde 7.35 b 4.54 cdef a 7.09 a 2 nd Spray cde b cd a 8.46 a Ist Spray 4.10 cdefgh 4.48 cdefg 4.00 cdefgh 4.79 cd 4.34 bc 2 nd Spray cde de cde 3.62 cde 3.32 bc Ist Spray 3.13 defgh 2.74 efgh 3.18 defgh 3.57cdefgh 3.16 de 2 nd Spray 2.32 de 2.43 de 2.18 de 2.42 de 2.34 cd Ist Spray 4.06 cdefgh 5.14 cd 4.91 cd 5.52 c 4.91 b 2 nd Spray 3.83 cde 3.37 cde 3.85 cde 4.11 cde 3.79 b Ist Spray 3.52 cdefgh 3.94 cdefgh 3.60 cdefgh 4.03cdefgh 3.77 cd 2 nd Spray 2.64 de 2.59 de 2.54 de 6.10 c 3.47 bc Ist Spray 2.37 h 2.53 fgh 2.10 h 2.51 gh 2.38 e 2 nd Spray 1.60 de de 1.52 e 2.43 de 1.51 d Ist Spray 3.63 c 4.36 b 3.72 c 5.38 a 2 nd Spray 3.04 b 3.68 b 2.97 b 5.57 a LSD value (insecticides) for Ist Spray =0.84, 2 nd Spray =1.24 LSD value (varieties) for Ist Spray =0.40, 2 nd Spray= 1.01 LSD value (varieties x insecticides) for Ist Spray =1.68, 2 nd Spray=2.48 s sharing the similar letters in the respective sprays do not differ significantly at P= 0.05 REFERENCES Abro, G.H., T.S. Syed, G.M. Tunio and M.A. Khuhro Performance of transgenic Bt cotton against insect pest infestation. J. Biotech. 3: Ahmad, Z Incidence of major cotton pests and diseases in Pakistan with special reference to pest management, Int l consultation on cotton production. Res. with focus on the Asian Region, Manila, Philippines. 17: Akber, R. and M. Hassan Comparative efficacy of some traditional and non-traditional insecticides against insect pests of okra. Pak. J. Entomol. 21: Allen, C.T., M.S. Kharboutli, C.E. Capps and L.D. Earnest Insecticides for tobacco budworm control. Special Rep. Arkansas Agric. Experim. Station. pp Anonymous Annual Report. Entomol. Section, Ayub Agric. Res. Instt. Faisalabad, Pakistan. pp Bariola, L.A. and P.D. Lingern Comparative toxicities of selected insecticides against pink boll worm ( Lepidoptera: Gelechiidae.) moths. J. Econ. Entomol. 77: Brickle, D.S., M.J. Sullivan, P. Dugger and D. Richter The efficacy of different insecticides and rates against bollworm in Bt and conventional Cotton. Proc. Beltwide Cotton Conf. Orlando, Florida, USA

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