Efficacy of Different Insecticides Against Maize
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Sarhad J. Agric. Vol.27, No.3, 2011 EFFICACY OF DIFFERENT INSECTICIDES AGAINST MAIZE STEM BORER, CHILO PARTELLUS SWINHOE (LEPIDOPTERA; PYRALIDAE) AT PESHAWAR AND SWAT VALLEYS OF KHYBER PAKHTUNKHWA, PAKISTAN MANZOOR AHMAD MASHWANI* FARMAN ULLAH*, SHAHID SATTAR*, SAJJAD AHMAD** and MUHAMMAD ANWAR KHAN* * Department of Plant Protection, Agricultural University, Peshawar – Pakistan. ** Department of Entomology, Agricultural University, Peshawar – Pakistan. ABSTRACT To study the relative efficacy of different insecticides as seed dressers, granules and foliar formulations against maize stem borer (MSB) (Chilo partellus) in maize crop, two experiments were conducted at Peshawar and Swat Valleys of Khyber Pakhtunkhwa, Pakistan. The results of both the field experiments were somewhat similar where seed dressers (Confidor® and Actara®) were found considerably more effective as compared to granules and foliar sprays. As a whole the insecticides treatments resulted in 50% reduction of MSB infestation as compared to control. Confidor® was the most effective among the treatments causing 97.30 % reduction in C. partellus infestation. This was followed by Actara® with 88% infestation reduction as compared to control. Key words: Chilo partellus, Maize stem borer, Seed dressers, Granules, Foliar insecticides Citation: Mashwani, A.M., Farman Ullah, S. Sattar, S. Ahmand and M.A. Khan. 2011. Efficacy of different insecticides against maize stem borer, chilo partellus swinhoe (Lepicoptera: Pyralidae) at Peshawar and Swat valleys of Khyber Pakhutunkhwa, Pakistan. Sarhad J. Agric. 27(3): 459-465 INTRODUCTION Maize stem borer, Chilo partellus Swinhoe (Lepidoptera: Pyralidae) is one of the major biotic constraints in successful maize and sorghum production worldwide (Pingali, 2001; James, 2003), particularly in Asia and Africa (Siddiqui & Marwaha, 1993; Arabjafari & Jalali, 2007). It has been reported to cause severe losses in maize crop throughout its geographical distribution including Pakistan. Yield losses of 24-75% have been reported by the attack of this pest alone (Kumar & Mihm, 1995, 1996; Kumar, 2002; Khan, 1983). Farid et al. (2007) reported 10 – 50% damage by maize stem borer in Peshawar valley. Yield losses caused by stem borers in Africa could be as high as 80% for maize (Van den Berg 2009) and as much as 88% in sorghum (Seshu Reddy, 1988). A variety of insecticide chemistries and formulations have been found effective against the pest. Granular formulations of chlorpyriphos and carbofuran were reported effective against the pest by Bhat and Baba (2007). Similarly Ullah et al. (1992) observed that granular application of insecticides showed better control of maize stem borer as compared to the emulsifiable concentrates (EC) as a foliar application at Peshawar, Pakistan. Seed treatment with carbofuron and endosulfan has also been reported as useful against the pest (Sekhon and Kanta, 1992). Contrary to the observations of Bhat and Baba (2007) and Ullah et al. (1992), Singh and Sharma (2009) determined that Chlorpyriphos was ineffective as compared to cypermethrin (foliar application). These contradictory observations and the introduction of newer chemicals in the market necessitate testing of these compounds for efficacy against the pest on regular basis. Keeping in view the importance of the crop, the devastating capacity of the pest and the ever dynamic pesticide market, the present research work was initiated to investigate the suitability of some insecticides for effective and safe suppression of C. partellus. MATERIALS AND METHODS To study the relative efficacy of different insecticides as seed dressers, granules and foliar formulations against Chilo partellus in maize crop, two experiments were conducted at Peshawar and Swat Valleys of Khyber Pakhtunkhwa, Pakistan. The chemicals and seed were obtained from local authorized dealers. Insecticides The insecticides used in the first experiment included two seed dressers of the Neonicotinoid group (Actar®a-70WS- Thiomethoxim and Confidor®- 70WS –Imidacloprid, each @ 5 gm kg-1seed), two granular insecticides of the Carbamate group (Monomehypo®- 5G @ 7 kg acre-1 , Furadan®- 3G Carbofuran @ 8 kg acre-1 and one granular formulation of Organophosphate (Padan® 3G –Cartap @ 9 kg acre-1), and four foliar insecticides; Manzoor Ahmad Mashwani et al. Efficacy of different insecticides against maize stem borer … 460 Imicon®-25 WP (Imidacloprid @ 100 gm acre-1), Dipterex® 80 SP (Trichlorofon, Organophosphate @ 1 gm l-1 ), Lorsban® 40EC- (Chlorpyriphos, OP @ 5 ml l-1) and Regent® 35 SC (Fipronil- Phenylpyrazoles @ 5 ml l-1). The second experiment included Actara®-70WS, Confidor®- 70WS, Furadan®- 3G and Deltaphos® 36EC (Deltamethrin10g+ Triazophos 350gm l-1, Pyrethroid+ Organophosphate 0.60 l acre-1). Simple tap water was used in the check plots in both the experiments. Procedure Experiment 1. Effects of insecticides on maize stem borer infestation at KP-AUP, Peshawar. A local, open pollinated maize variety “Azam” was sown in a randomized complete block design (RCBD), with four replications. The crop was sown on a well-prepared seedbed, using a single row hand drill planter. The plot size was 5 × 4 m2, having 5 rows and each row was having initial plantation of about 100 seedlings. The row-to- row distance was 75 cm. Plant to plant distance was initially 5 cm but latter on maintained to about 20 cm. A buffer zone of 1 meter wide was kept between the plots to isolate them from each other. A basal dose of 48 kg Nitrogen -1 -1 -1) acre as urea and 15.6 kg phosphorus acre (36 kg P2O5 acre as single super phosphate was applied. All the phosphorus and 1/3 of the nitrogen were applied at the time of sowing. The remaining 2/3 of the nitrogen was applied in equal split doses at the initial reproductive and tasselling stage. The first irrigation was given two (2) weeks after sowing and subsequent irrigations were given as needed. Two hoeing were made for weed eradication while one earthing up was made 4 weeks after sowing. All the treatments were left to natural infestation. Seed dressers were applied 24 hours prior to planting and insecticides (both granules and foliar spays) were applied 26 days after emergence. Experiment 2. Effects of insecticides on maize stem borer infestation at Madyan, Swat. In the light of the first experiment, a second experiment with limited number of treatments was conducted at Madyan, Swat. The same maize variety “Azam” was sown in randomized complete block design with three replications. Confidor® and Actara® were applied as a seed dresser 24 hours before seed sowing. Furadan® was applied as granules at the base of the plants and Deltaphos® was applied as a foliar spray, 21 days after emergence. All agronomic practices were kept similar as explained in the previous experiment. Data collection and Analysis For the extent of infestation, leaf holes, larval excreta, leaf scratches, dead heart and presence of larvae were used as criteria for infested plants which was then converted into total percent infestation and mean percent infestation for the season. The first observation on maize stem borer infestation was made 25 days post emergence while the rest of observations were made at weekly intervals for the first experiment and fortnightly in case of the second one. MSB population trend and treatment means data were analyzed using combined analysis of variance. Important pre planned comparisons were done in ANOVA and Fisher’s LSD test was used to compare treatments with check. RESULTS AND DISCUSSION Experiment 1 Data on maize stem borer infestation as affected by various insecticides at Khyber Pakhtunkhwa Agricultural University, Peshawar (KP AUP), are given in (Table I). The data given in the third column (April 14) were recorded on plots before application of insecticides (used as granules and spray) and on check plots, and on plots in which seed treated with Confidor® and Actara® had been planted, so in this column only the effects of seed dressers are evident and the other insecticides effect is not there as these were applied after recording the data at this date. The data given in the fourth column were recorded on the next day of application of the insecticides as granules and spray and thereafter, data were recorded at weekly interval. The statistical analysis of the Maize Stem Borer (MSB) data recorded at each date (weekly interval) and of the seasonal average data showed that differences among the various insecticides were significant at all the dates as well as cumulative average for each season. The combined analysis of the data from all the six dates showed that main effect of insecticides treatments and time of recording data were significant. Interaction between insecticides treatments and times of recording data was also significant Table I. Sarhad J. Agric. Vol.27, No.3, 2011 461 Table I Percent maize stem borer infestation (pre and post application of various insecticides) with time and seasonal average stem borer infestation as affected by insecticides in maize planted at New Developed Farm, Agric. Univ. Peshawar, Pakistan Treatments Mode of April 14 April 15 April 21 April 28 May 5 May 12 Seasonal Application †† average† Confidor Seed dresser 2.25 2.36 3.63 4.52 5.74 7.10 4.27 I Actara Seed dresser 2.75 3.02 4.36 5.78 6.50 11.72 5.69 H Padan Granules 7.33 7.96 8.15 8.34 10.27 10.27 8.72 F Furadan Granules 7.66 8.19 8.33 8.33 8.00 8.00 8.09 G Monomehypo Granules 8.13 8.91 9.08 9.36 12.00 12.00 9.91 D Amicon Spray 8.33 9.00 9.36 9.69 9.69 9.69 9.29 E Regent Spray