Studies on the Bio-efficacy of new insecticide molecules against insect pests in cotton aicrp on cotton

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1 2017; 5(6): E-ISSN: P-ISSN: JEZS 2017; 5(6): JEZS Received: Accepted: Ambarish S Shashi Kumar C Somu G Shivaray Navi Studies on the Bio-efficacy of new insecticide molecules against insect pests in cotton aicrp on cotton Ambarish S, Shashi Kumar C, Somu G and Shivaray Navi Abstract A field experiment was conducted at AICRP on Cotton KVK, Chamarajnagar, UAS, Bangalore, during to assess the efficacy of different combination insecticides. Totally 3 sprays were taken up at 40, 80 and days after sowing using manually operated knapsack sprayer. The mean of three sprays indicated that, application g ai/ha recorded a lower number of whiteflies per leaf (0.41) and Leaf hopper (0.48). Whereas the lower number of aphids per leaf (1.71) and thrips (0.77) were recorded in the application of Sulfoxaflor 108 gai/ha. While untreated control recorded the higher number of thrips (13.22), leaf hopper (3.71), whiteflies (2.88) and aphids (36.33) per leaf. The incidence of bollworm was lowest in Spinetoram 10% 36 g ai/ha. Keywords: cotton; insecticides; sucking pests; bollworms Introduction Cultivation of cotton under diversified agro climatic situations makes the crop to suffer a lot of different kinds of pests and diseases. Large area under rainfed situations and extensive replacement of conventional varieties with superior hybrids made the crop easily vulnerable to insect pests. In India cotton crop known to attacked by 162 species of insect pests from sowing to harvesting and which causes loss up to per cent [1]. Cotton pests can be primarily divided into bollworms and sucking pests. Among sucking pests, aphid, Aphis gossypii (Glover), leaf hoppers, Amrasca biguttula biguttula (Ishida), thrips, Thrips tabaci (Lind.) and whitefly, Bemisia tabaci (Genn.) are of major importance. These sucking pests occur at all the stages of crop growth and responsible for indirect yield losses. A reduction of per cent in seed cotton yield due to sucking pests has been reported by Satpute et al. [2]. Sucking pests, also referred to as sap feeders, limit the realization of the potential productivity of cotton, they are deleterious to the cotton plant growth and development by being assimilated sappers, stand reducers and light stealers. The heavy infestation of nymphs and adults of sucking pests resulted in leaf yellowing, wrinkled leaves, leaf distortion and oily spots on leaves. Secondly, they found to secrete honey dew which leads to the growth and development of sooty mould fungus (Capnodium sp.) on leaves. The fungus inhibits the photosynthetic activity of the plants resulting into chlorosis that affect the seed cotton yield. Moreover, whitefly also act as a vector to transmit leaf curl disease in cotton. Keeping these points in view it was tried to find out the effective chemical for the management of sucking pests and boll worms in cotton. Correspondence Ambarish S Materials and Methods The field experiment was conducted at AICRP on Cotton, KVK, Chamarajanagar. The crop was sown during , Kharif season in a Randomized Block Design (RCBD) The experiment was configured with 11 treatments which were replicated 3 times using Suraj variety of cotton (non bt) in a plot size of 3.56 x 4.5 m for each treatment. The crop was raised with a spacing of 90 x 60 cm by following all recommended package of practices of University of Agricultural Sciences, Bangalore [3] except plant protection measures. Pesticides were applied at 40, 80 and days after sowing by using manual hand operated knapsack sprayer. Sufficient care was taken to avoid Drift problems to adjacent treatments. The observations were recorded by following the standard procedure for all sucking pests and bollworms. In each treatment and in each replication five plants were selected randomly and tagged. The number of aphids, thrips, leafhoppers and white flies were counted on top growing (3, 5 and 7 leaves on the main stem from the top) leaves. ~ 544 ~

2 Population count was made one day before spray and 7 days after sprays. The mean population per leaf per plant was estimated and subjected to statistical analysis, ANOVA test [4]. Table 1: List of insecticides evaluated along with their dosages against insect pests of cotton. S. No Insecticide Dose (g ai/ha) T1 T2 T3 Spinetoram 10% w/w 30 T4 Sulfoxaflor 30% 90 T5 Spinetoram 10% w/w 36 T6 Sulfoxaflor 30% 108 T7 T8 Pyriproxyfen 5% EC 37.5 T T10 Water spray T11 un sprayed Results Leaf hopper (Amrasca biguttula biguttula, Ishida) The mean of 3 sprays indicated that the lowest number of leaf hopper population per leaf (0.48) was recorded in g ai/ha, which was statistically on par with the treatments Sulfoxaflor 108 g ai/ha (0.5), Sulfoxaflor 90 g ai/ha (0.58) and Sulfoxaflor 30% w/w g ai/ha (0.61).While other treatments such g ai/ha and Pyriproxyfen 5% 37.5 g ai/ha recorded slight higher population ie, 1.69 leaf hoppers per leaf. However Fenpropathrin EC g ai/ha (1.77/leaf) and Spinetoram 10% 30 g ai/ha shows (1.87/leaf). While the highest population was recorded in the control water spray such as (3.71/leaf) and control un sprayed treatment (3.58/leaf) (Table II). Thrips (Thrips tabaci, Linnman) The mean of 3 sprays indicated that the lowest number of thripspopulation per leaf in the treatment Sulfoxaflor 108 g ai/ha (0.77), it should be on far with the treatments such as Sulfoxaflor 90 g ai/ha (1.0), Spinetoram 10% w/w g ai/ha (1.06), Spinetoram 10% w/w g ai/ha (1.13). While the highest population was recorded in the control un sprayed treatment and water spray (13.22) and (12.53), respectively (Table II). Aphids (Aphis gossypii, Glover) The mean of 3 sprays shows that the lowest number of aphid population per leaf (1.51) was recorded in the Sulfoxaflor 108 g ai/ha, it should be on par with the g ai/ha (1.70), Sulfoxaflor 30% w/w g ai/ha (2.00) and Sulfoxaflor 90 g ai/ha (2.34). While the highest population was recorded in the control water spray such as (36.33/leaf) and control un sprayed treatment (34.39/leaf) (Table III). Whiteflies (Bemisia tabaci, Gennadius) The mean of 3 sprays indicated that the lowest number of white flies population per leaf (0.41) was recorded in g ai/ha, it should be on far with the treatments Spinetoram 10% w/w g ai/ha (0.46), and Sulfoxaflor 90 g ai/ha (0.47). While all other treatments are found to be on far with each other, except in the control plots. In control plot 2.88 in water spray and 2.59 in the unsprayed plots (Table III). Bollworms: At 150 days after sowing of the crop the lowest incidence of bollworms damage was noticed in Spinetoram 10% 36 g ai/ha (0.40 damaged bolls/plant) it was found to be on par with the all the combinations of spinetoram treated plots (Table IV). Discussion For the management of insect pests in cotton application g ai/ha recorded a lower number of whiteflies per leaf (0.41) and Leaf hopper (0.48). Whereas the lower number of aphids per leaf (1.71) and thrips (0.77) were recorded in the application of Sulfoxaflor 108 g ai/ha. Hence the insecticide molecule Sulfoxaflor 30% and its combinations were promising insecticide for the management of all sucking insect pests in cotton than other insecticide molecules tested. For the management of bollworms spinetoram treated plots shows the less number of bolls damaged per plant. Hence for the management of sucking pests and bollworms in cotton spinetoram and sulfoxaflor combinations will found to be effective in cotton. Similar studies also show that Sulfoxaflor is part of chemical class of insecticides known as the sulfoxamines, a group that has not previously been associated with crop protection chemistries. It exhibits a mode of action that is unique among all other insecticides as it kills target pests by interacting with the insects nicotinic acetylcholine receptors in a manner which is contrasted to that of neonicotinoid insecticides [5]. The perusal of literature revealed that there is scanty work on this aspect, However the present results are in agreement with the findings of Melissa [6] reported that application of sulfoxaflor at 50 g ai/ ha provided good control of Tarnished Plant Bug (Hemiptera: Miridae) in Cotton and yield levels similar to that observed with acephate. Sulfoxaflor is the xylem-mobile and is especially effective in controlling wide variety of sap-feeding or piercing & sucking insects by contact and also by ingestion [7]. Bhanu [8] reported that Sulfoxaflor 24 SC at both the dosages viz., 75 and 90 g a.i/ha reduced the buildup of plant hoppers in both the seasons and was superior to other insecticides with a mean per cent reduction of plant hoppers population by 88.0 and 85.7, respectively during Kharif 2011 and 74.3 and 84.4 respectively, during Rabi , over the untreated control [6]. Sulfoxaflor use rate of 25 g ha 1 against cotton aphid (Aphis gossypii (Glover) outperformed acetamiprid (25 g ha 1 ) and dicrotophos (560 g ha 1 ). Sulfoxaflor (50 g ha 1 ) provided a control of sweet potato whitefly equivalent to that of acetamiprid (75 g ha 1 ) and imidacloprid (50 g ha 1 ) and better than that of thiamethoxam (50 g ha 1 ) [9]. ~ 545 ~

3 Table 2: Efficacy of newer insecticides against leaf hoppers and thrips in cotton. Dose (g.ai/ha) Number of leaf hoppers per leaf Number of thrips per leaf 1 DBS 7 DAFS 7 DASS 7 DATS Mean 1 DBS 7 DAFS 7 DASS 7 DATS Mean (1.75) (1.18) (1.28) (1.32) (1.26) (3.47) (1.68) (1.34) (1.33) (1.46) (1.82) (1.14) (1.23) (1.26) (1.21) (3.38) (1.70) (1.26) (1.29) (1.44) Spinetoram 10% w/w (1.80) (1.64) (1.64) (1.78) (1.69) (3.43) (2.56) (2.51) (2.12) (2.40) Sulfoxaflor 30% (1.93) (1.19) (1.31) (1.26) (1.25) (3.43) (1.51) (1.40) (1.33) (1.41) Spinetoram 10% w/w (1.85) (1.63) (1.76) (1.90) (1.77) (3.44) (2.48) (2.50) (2.23) (2.41) Sulfoxaflor 30% (1.77) (1.14) (1.29) (1.23) (1.22) (3.32) (1.46) (1.25) (1.26) (1.33) (1.70) (1.57) (1.59) (1.75) (1.64) (3.56) (2.50) (2.54) (2.15) (2.40) Pyriproxyfen 5% EC (1.00) (1.55) (1.58) (1.76) 1.63) (3.45) (2.44) (2.16) (1.77) (2.14) (1.81) (1.51) (1.68) (1.78) (1.66) (3.46) (2.56) (2.25) (1.78) (2.22) Water spray (1.74) (1.85) (2.25) (2.28) (2.13) (3.45) (3.63) (3.75) (3.92) (3.77) un sprayed (1.77) (1.87) (2.28) (2.32) (2.17) (3.47) (3.58) (3.62) (3.83) (3.68) S.Em C.D (p=0.05) NS NS C.V % DBS: Day before spraying, DAFS: Days after the first spray, DASS: Days after the second spray, DATS: Days after the third spray Figures in parentheses indicate x +1 transformed values Table 3: Efficacy of newer insecticides against Aphids and Whiteflies in cotton. Number of Aphids per leaf Number of White flies per leaf Dose (g.ai/ha) 1 DBS 7 DAFS 7 DASS 7 DATS Mean 1 DBS 7 DAFS 7 DASS 7 DATS Mean (4.90) (2.17) (1.64) (1.26) (1.73) (1.58) (1.17) (1.26) (1.18) (1.21) (4.82) (2.00) (1.60) (1.24) (1.64) (1.57) (1.16) (1.22) (1.17) (1.19) Spinetoram 10% w/w (4.83) (4.53) (4.65) (4.57) (4.58) (1.59) (1.33) (1.32) (1.32) (1.32) Sulfoxaflor 30% (4.84) (2.37) (1.64) (1.32) (1.83) (1.68) (1.18) (1.25) (1.20) (1.21) Spinetoram 10% w/w (5.07) (4.69) (4.55) (4.42) (4.55) (1.73) (1.29) (1.34) (1.48) (1.37) Sulfoxaflor 30% ~ 546 ~

4 (5.22) (1.93) (1.52) (1.22) (1.58) (1.63) (1.21) (1.30) (1.22) (1.25) (5.13) (4.40) (4.43) (4.53) (4.45) (1.56) (1.22) (1.32) (1.18) (1.24) Pyriproxyfen 5% EC (4.96) (4.62) (4.65) (4.56) (4.61) (1.60) (1.24) (1.29) (1.22) (1.25) (5.05) (4.40) (4.51) (4.65) (4.52) (1.77) (1.55) (1.43) (1.48) (1.49) Water spray (5.04) (5.45) (6.08) (6.28) (5.95) (1.60) (1.69) (1.82) (2.14) (1.89) Un sprayed (5.07) (5.51) (37.83) (6.54) (6.11) (1.62) (1.71) (1.94) (2.22) (1.97) S.Em C.D (p=0.05) NS C.V % DBS: Day before spraying, DAFS: Days after the first spray, DASS: Days after the second spray, DATS: Days after the third spray Figures in parentheses indicate x +1 transformed values Table 4: Efficacy of insecticides against Bollworms in cotton. Number of damaged bolls per plant 110 Das 150 Das T T T T T T T T T T T S.Em C.D (p=0.05) C.V % ~ 547 ~

5 g ai/ha were the best and effective chemical for the management of sucking pests as well as bollworms in cotton when compared to the other chemicals tested. Acknowledgements To KVK, Chamarajanagara, University Agricultural Sciences, Bangalore India) for providing facilities for the conduct of this work. References 1. Agarwal RA, Gupta GP, Garg DO. Cotton pest management in India. Res. Publn, Azadnagar, Delhi, 1984, Satpute US, Patil VN, Katole SR, Men VD, Thakare AV. Avoidable field losses due to sucking pests and bollworms in cotton. Journal of Applied Zoological Research ; (2): Anonymous. Package of practices for field crops, University of Agricultural Sciences, Bangalore, Gomez KA, Gomez AA. Statistical Procedure for Agricultural Research, 2nd edn, Wiely, New York, USA. 5. Babcock JM, Gerwick CB, Huang JX, Loso MR, Nakamura G, Nolting SP. Biological characterization of sulfoxaflor, a novel insecticide. Pest management science. 2011; 67: Melissa WS, James D, Thomas SP, Nolting B, Rogers L, Jeff G et al. Field Evaluations of Sulfoxaflor, a Novel Insecticide Against Tarnished Plant Bug (Hemiptera: Miridae) in Cotton. The Journal of Cotton Science. 2012; 16: Andre A. A demand analysis for the new dow agrosiences insecticide, sulfoxaflor, among california pest control advisors. Presented to the Faculty of the Agribusiness Department California Polytechnic State University degree in Bachelor of Science, Bhanu K, Vasanta N, Mallikharjuna M, Bharata. Sulfoxaflor: a new insecticide molecule effective against planthoppers in rice. Indian Journal of Plant Protection. 2015; 42(4): Jonathan MB, Clifford BG, Jim H, Michael RL. Biological characterization of sulfoxaflor, a novel insecticide. Pest Management Science. 2011; 67(3): ~ 548 ~