Efficacy of Different Neem (Azadirachta indica) Products in Comparison with Imidacloprid against English Grain Aphid (Sitobion avenae) on Wheat.
Different neem (Azadirachta indica L.) extracts (leaf and seed) and seed oils were tested against English grain aphid (Sitobion avenae F.) with a neonicotinoid, imidacloprid on wheat. All neem oils and neem seed kernel extract proved comparatively more effective in laboratory bioassay studies, with LC50 values ranging from 0.34 to 1.10 (Percent) . In field-cage experiment, neem seed oil-hexane was statistically similar with imidacloprid followed by neem seed oil-expeller and neem seed kernel extract, while neem seed oil-ethanol was at par with imidacloprid. On the basis of cumulative insect days in field trials, neem seed oil- expeller proved as effective as imidacloprid in controlling the aphids, while except neem seed cake extract, all other treatments were statistically at par with imidacloprid. Non-significant differences were found in the population of mummified aphids between control and neem seed kernel extract, neem leaf extract, neem seed oil-hexane, neem seed cake extract and neem seed oil-expeller.
There existed non-significant differences in all treatments regarding aphid predators. Maximum increase in wheat yield (7.28 q/ha) was observed in neem seed kernel extract treated plots followed by those of imidacloprid (7.23 q/ha). Application of imidacloprid resulted in maximum cost-benefit ratio (1:1.34) followed by that of neem seek kernel extract 5 (Percent) (1:1.31). If the additional cost of loss of beneficial organisms and environmental risks posed by the application of synthetic insecticides is considered, the cost-benefit ratio of neem seed kernel extract may be comparable to that of imidacloprid and may be used against wheat aphids. (c) 2013 Friends Science Publishers
Keywords: Wheat; Sitobion avenae; Neem leaf extract; Neem seed extract; Neem oil; Imidacloprid
Wheat is the peoples staple food in Pakistan; which ranks 8th largest wheat producer in the world and accounts for 2,09,58,000 MT production on an area of 8549.9 thousand hectares (GOP, 2008). Wheat crop is affected both directly and indirectly with infestation of aphids. The direct damage is caused by sucking cell sap from the tender leaves and young shoots resulting in distortion, stunting, leaf curling and wilting. Indirect damage occurs through the transmission of plant viruses and development of sooty mould on honey dews secreted by aphids (Rossing et al.,1994; Akhtar and Mujahid, 2006; Zeb et al., 2011). Aphids can cause 35- 40 (Percent) yield losses directly (Kiechefer and Gellener, 1992) and 20-80 (Percent) losses by transmitting viral and fungal diseases (Trdan and Mileroj, 1999). Due to certain climatic changes, aphid population has been increasing for the last few years on wheat crop and has attained the status of pest in all wheat growing areas of Pakistan (Aheer et al.,2008).
English grain aphid (Sitobion avenae F.) is one of the most dominant aphids of wheat in many countries of the world including subcontinent. It causes damage by infesting upper mature leaves, spikes and heads of the plants (Tradan and Mileroj, 1999). Maximum loss in yield occurs in case of infestation between ear emergence and flowering which may reach up to 14 (Percent) (Liu et al., 1986).
Control of aphids with synthetic insecticides is not desirable on wheat due to many bad effects like pesticide residues, destruction of predators and parasites, environmental pollution, destabilization of ecosystem and enhanced resistance to insecticides in pests. So, there is a need to explore eco-friendly and cost-effective control methods. Among available non-chemical weapons, neem (Azadirachta indica) has the potential to be used as a substitute of synthetic insecticides (Schmutterer, 1995; Farooq et al., 2011; Basedow et al., 2002; Rashid et al.,2012). Products derived from seeds, leaves, kernels and other parts of the neem tree are inexpensive and biodegradable naturally available source (Shafeek et al.,2004) and have been found to be effective against different pests (Gahukar, 2000; Liang et al., 2003; Senthil Nathan et al., 2005).
According to Schmutterer and Singh (2002), more than 540 insect species including key insect pests of agricultural and horticultural crops have been found to be susceptible to azadirachtin and exhibited various behavioral and physiological effects (Satti et al., 2010).
Present study was conducted with the aim to find out the efficacy of three different neem extracts and their results were compared with imidacloprid (the most widely used insecticide worldwide against sucking insects including aphids) in laboratory, semi field and field conditions to calculate their cost-benefit ratio. So that the farmers may adopt environment friendly and cost effective practices for the management of cereal aphid.
Materials and Methods
Neem Aqueous Extracts
To make neem leaf extract (NLE), one kg of green neem leaves were mixed with water to make 5 L of the solution to get 20 (Percent) of NLE. The leaves were soaked overnight in water. The next day, they were ground and extract was filtered. To the filtrate, an emulsifier like Khadi soap (soap with no detergent) was added @ 1 mL in 1 L water. In order to make neem seed kernel extract (NSKE), outer coat of neem kernel was removed and pounded (hammered) gently, in such a way that no oil came out. Fifty grams of neem kernel powder (between three and eight months old) was gathered in muslin pouch and soaked overnight in water to make up the volume to 1 L (5 (Percent) . The pouch was squeezed and the extract was filtered and khadi soap (soap with no detergent) was added at the rate of 1 mL/L water as an emulsifier One hundred grams of neem cake was added in water to make volume 1 L of solution (10 (Percent) to prepare neem cake extract (NSCE) The neem cake was put in a muslin pouch and soaked in water overnight.
It was then filtered and an emulsifier was added at the rate of 1mL for 1 L of water (Musabyimana et al., 2001).
Neem seed oil-ethanol (NSO-ethanol) was prepared by grinding two hundred grams de-coated neem seeds in a blender to make seed powder, which was added to ethanol to make up to 1 L volume and kept for a week. The solution was filtered through a filter paper and evaporated with the help of soxhlets apparatus to get solvent free oil. The oil was weighed to calculate the concentration of oil and solution of desired concentration was made. For making neem seed oil- hexane (NSO-hexane), same method was followed as described above, only hexane was used in place of ethanol for extracting neem oil (Charmaine et al., 2005). Neem oil extracted by expeller (NSO-expeller) was purchased from the local market. The concentration of oil was calculated (by taking information from the shopkeeper) and solution of desired concentration was made (Musabyimana et al.,2001).
Noenicotinoid insecticide, imidacloprid (Confidor 25 WG) was used as a standard to compare of the results of different neem products against wheat aphids, which is considered most widely used insecticide against sucking pests including aphids (Caroline, 2001).
Toxicological Studies of Different Neem Extracts, Oils and Imidacloprid
Toxicological studies of different neem products were conducted in the laboratory under control conditions (25 +- 2oC and 75 +- 5 (Percent) RH). Seeds of wheat (variety Wafaq) were sown in small pots (15 cm diameter) in field conditions, containing top layer fertile soil, sand and well rotten farm yard manure in 1:1:1 ratio. After 21 days of germination, thinning was done so that each pot contained only three seedlings. These pots were shifted into the laboratory. For each product, a stock solution of desired concentration was prepared with water and subjected to seven serial dilutions. On each pot, ten female aphids (4th instar) were released on wheat seedlings and allowed to settle down. Each pot was covered with round plastic sheet having muslin cloth on its top. Next day these aphids were counted again and dead ones were replaced with new healthy aphids. These pots were sprayed thoroughly with each test product with the help of hand sprayer and covered again with round plastic sheets having muslin cloth.
Each concentration was comprised of four replicates and forty aphids. Four pots were sprayed with only water in each bioassay to serve as a control. The data regarding mortality of aphids were taken 3 days after application of insecticides. All the data were processed through probit analysis using Polo-PC software (Russel et al., 1977).
Testing of Different Neem Extracts, Oils and Imidacloprid in Semi Field Conditions
Toxicological studies of different neem products were conducted in the semi natural condition. Wheat plants were sown in earthen pots in field conditions. After 35 days of germination thinning was done so that each pot contained only five tillers. These pots were kept in iron cages covered with muslin cloth. On each pot twenty five 4th instar female aphids (Sitobion avenae F.) were released on wheat plants and allowed to settle down. These pots were covered with iron cages containing muslin cloth. Next day these aphids were counted again. Most of the aphids were found settled while dead aphids were replaced the new healthy ones. Then these pots were sprayed thoroughly with insecticide preparation with the help of calibrated sprayer and covered again. Each treatment was replicate four times. Four pots were sprayed with water only to serve as a control. The data regarding mortality of aphids were taken 3, 5 and 7 days after application.
All the data was subjected to analysis of variance (ANOVA) and the means were compared by using Duncan's Multiple Range test at 5 (Percent) level of probability (Steel et al., 1996).
Testing of Different Neem Extracts, Oils and Imidacloprid in Field Conditions
The experiment was laid out in Completely Randomized Block Design with eight treatments and three replicates. Wheat crop was sown on 04-11-2010, with 4.5x 9 m plot size. These plots were separated from each other by keeping distance of 0.6 m between each treatment and 1ft between each replicate. All agronomic practices were applied in all experimental plots according to the recommended rates. The plots were observed continuously for the infestation of cereal aphids and application of neem products was done when their population reached 10 aphids per tiller. Application was mad with calibrated knapsack sprayer (Gardena, Model Art 884) during morning hours.
The data regarding wheat aphids and their natural enemies were taken one day before application and 4, 7 and 11 days after application. Further application was not needed because the aphid's population became low in all the experimental plots including control. In each experimental plot nine tillers were clipped randomly following zigzag pattern and shifted in plastic zip bags. These bags were kept in ice box and shifted to laboratory. The data regarding aphids, mummified aphids, lady bird beetles, syrphid fly larvae and green lace wing larvae were taken by counting their number from the whole tillers. The data were converted to cumulative insect days to get an estimate of both intensity and duration of S. avenae and its natural enemies. An insect day may be defined as one insect feeding on one plant for 24 h.
Insect days for a sampling date were calculated with the formula adapted from Ruppel (1983) as ad = ([Xd + Xd[?]1]/t, where ad = number of insect days between the current sampling date and previous sampling date. Xd = Number of insects per plant on the current sampling date. Xd[?]1= Number of insects per plant on previous sampling date, and t = the number of days between sampling dates. Cumulative insect days were calculated by summing the number of insect days for each sampling date.
Yield of wheat was taken by randomly selecting three spots of 1 m2 from each experimental plot. The plants were cut, shifted into plastic bags and brought to the lab. Wheat grains were threshed manually after drying, weighed with electric balance and average yield/m2 was found out for each plot.
All the data was subjected to ANOVA and the means were compared by using Duncan's Multiple Range test at 5 (Percent) level of probability (Steel et al., 1996).
In the lab bioassay, NLE and NSCE were found least effective against English Grain aphid with comparatively more LC50 values than the other neem preparations. NSKE was the most with 1.10 (Percent) LC50 value. All the three neem oils proved more effective with comparatively less LC50 values, and NSO-n-hexane appeared most toxic than the other two, with 0.34 (Percent) LC50 value. The synthetic insecticide imidacloprid proved the most toxic (LC50= 2.85 ppm) than all the neem products (Table 1).
Data regarding mortality (Percent) of English grain aphid showed significant differences among all test formulations, 3, 5 and 7days after application of different neem products revealed. Maximum aphid mortality was observed in plants treated with imidacloprid and NSO-n-hexane followed by NSO- ethanol, NSO-expeller and NSKE treated plants (Table 2). All the neem oils performed better than neem extracts except NSKE. Minimum mortality was observed in case of NLE and NSCE.
All the neem treatments significantly reduced the pest population. Imidacloprid and NSO-Expeller gave the lowest cumulative insect days, while all other neem treatments except NSCE were at par with imidacloprid, showing effectiveness of all neem oils and two extracts. Highest cumulative insect days of mummified aphids were in found in control. Non significant differences were found between control and NSKE, NSCE, and NSO-n-hexane treated plots. Imidacloprid exerted relatively more adverse impact on parasitized aphids with lowest cumulative insect days than all other treatments. The comparison of cumulative insect days showed no significant difference among all treatments in case of aphid predators (lady bird beetles, syrphid fly and green lacewing). All the neem preparations reduced the cereal aphid population in field trials, but their impact on aphid parasitoids was low, in contrast to imidacloprid treated plots.
The CBR of different neem preparations and imidacloprid was calculated to find out the best treatment with maximum control of the pest and yield with a minimum cost. The maximum increase in the yield was observed to be 7.28 q/ha in those plots, where NSKE (5 (Percent) was applied followed by imidacloprid (7.23 q/ha). The results pertaining to the wheat yield and cost benefit ratio in different methods of control are depicted in Fig. 1. The application of NSKE (5 (Percent) resulted in a CBR of 1:1.31 and was found to be the most economical as compared to that of all the other neem preparations followed by NSO-Expeller 0.5 (Percent) (1:1.17) and NLE 20 (Percent) (1:1.15). Application of imidacloprid (neonicotinoid synthetic insecticide) resulted in maximum CBR i.e., 1:1:34.
Table 1: Toxicity of different neem formulations and imidacloprid against English grain aphid (Sitobion avenae) after 72 h
Insecticide###LC50 (95 Percent CL)###Fit of probit line
###Slope (+- SE)###X2###df###Heterogeneity
Neem Leaf Extract###(Percent)###14.75(8.92-32.49)###1.00 +- 0.18###0.38###5###0.08
Neem Seed KernalExtract (Percent)###1.10(0.73-1.71)###1.05 +- 0.16###0.11###5###0.02
Neem Seed Cake Extract###(Percent)###19.29(8.19-144.30)###0.74 +- 0.184###0.12###5###0.02
Neem Seed Oil (Ehanol)###(Percent)###0.67(0.44-0.99)###1.29 +- 0.20###1.16###5###0.23
Neem Seed Oil (n -Hexane)(Percent)###0.34(0.23-0.51)###1.46 +- 0.16###1.17###5###1.17
Neem Seed Oil (Expeller) (Percent)###0.67(0.46-1.04)###1.10 +- 0.16###1.73###5###0.35
Imidacloprid(Confidor)ppm###2.85(1.78-4.11)###1.29 +- 0.17###1.40###5###0.28
Table 2: Means comparison of mortality (Percent)) of English grain aphid (Sitobion avenae) after application of different neem formulations and imidacloprid in semi-field conditions.
Neem Leaf Extract###(Percent)###26.0 +- 2.58 d###39.0 +- 2.52 d###46.0 +- 2.58 c
Neem Seed Kernel Extract (Percent)###75.0 +- 2.52 a###79.0 +- 1.63 c###89.0 +- 1.91 b
Neem Seed Cake Extract###(Percent)###16.0 +- 2.31 e###33.0 +- 1.91 d###46.0 +- 2.58 c
Neem Seed Oil- Ethanol###(Percent)###62.0 +- 2.58 bc###86.0 +- 2.58 b###96.0 +- 1.63 ab
Neem Seed Oil - n-Hexane (Percent)###66.0 +- 2.58 b###92.0 +- 2.83 ab###100.0 +- 0.00 a
Neem Seed Oil - Expeller (Percent)###58.0 +- 2.00 c###79.0 +- 3.00 c###89.0 +- 6.19 b
Imidacloprid (ppm)###77.0 +- 1.91 a###95.0 +- 1.00 a###100.0 +- 0.00 a
Control###5.0 +- 1.00 f###7.0 +- 1.00 e###9.0 +- 1.00 d
Means sharing similar letters are not significantly different (P Greater than 0.05)
DAT = Days after treatment
Table 3: Cumulative insect-days (per plant) of English grain aphid (Sitobion avenae) and its natural enemies after application of different neem formulations and imidacloprid in field experiments
Treatment###Aphids###Mummified Aphids###Lady bird Beetles###Syrphid fly Larvae###Green Lace Wing larvae
NeemLeafExtract###60.91 +- 3.37 bc###3.25 +- 0.32 ab###1.00 +- 0.61 a###0.148 +- 0.07 a###0.278 +- 0.18 a
Neem Seed Kernel Extract###63.30 +- 1.91 bc###4.17 +- 0.47 a###1.09 +- 0.47 a###0.130 +- 0.13 a###0.203 +- 0.20 a
Neem Seed Cake Extract###72.59 +- 8.86 b###4.09 +- 0.28 a###0.54 +- 0.16 a###0.074 +- 0.07 a###0.000 +- 0.00 a
Neem Seed Oil (Ethanol)###63.28 +- 2.25 bc###2.37 +- 0.46 b###0.0 +- 0.00 a###0.074 +- 0.07 a###0.000 +- 0.00 a
Neem Seed Oil (n-Hexane)###58.28 +- 3.58 bc###4.00 +- 0.48 a###0.54 +- 0.15 a###0.074 +- 0.07 a###0.074 +- 0.07 a
Neem Seed Oil (Expeller)###56.28 +- 6.66 c###3.30 +- 0.26 ab###0.0 +- 0.00 a###0.000 +- 0.00 a###0.000 +- 0.00 a
Imidacloprid###53.37 +- 2.59 c###0.94 +- 0.38 c###0.46 +- 0.36 a###0.000 +- 0.00 a###0.000 +- 0.00 a
Control###92.48 +- 4.76 a###4.19 +- 0.19 a###0.74 +- 0.44 a###0.000 +- 0.00 a###0.000 +- 0.00 a
Means sharing similar letters are not significantly different (P Greater than 0.05)
The results of toxicological studies support the effectiveness of NSKE and all the neem seed oils against English grain aphid. Neem oils and neem seed extracts based formulations have been reported to give significant reduction against green peach aphid on pepper, current lettuce aphid on lettuce and strawberry aphids on strawberry with LC50 values ranging from 0.2 to 1.4 (Percent) (Lowery et al., 1993). In the present studies, NSO-hexane proved better insecticide than NSO-ethanol and NSO-expeller with lowLC50 values. Similar trend was observed with the application of different neem preparations against Lipaphis erysimi, where neem seed oil extracted in hexane exhibited much higher insecticidal activity the neem seed aquous and ethanolic extracts of neem (Singh et al., 1988). Khalequzzaman and Nahar (2008) found that azadirachtin was more toxic than imidacloprid, malathion, carbosulfan and cymbush to control four aphid species namely Aphis craccivora, A. gossypii, Myzus persicae and Lipaphis erysimi.
The results of field cage experiments revealed varied response of neem water extracts and oils against wheat aphids. NSO-hexane and NSO-ethanol performed better than NSO-expeller and produced statistically similar results to imidacloprid. These differential effects of neem products against test aphid species may be attributed to the differences in the methods of extraction influencing the bioactivity of the neem formulations. Neem oils may help to spread the chemicals on both plant and animal surface and allow them to penetrate into the insects, therefore the products containing both azadirachtin and oils may exhibit better aphicidal activities than either ingredients alone (Stark and Walter, 1995). Previous studies advocate the effectiveness of neem formulations against different aphids in the semi field conditions. Application of AZ (180 ppm) on potted citrus plants reduced 100 (Percent) citrus aphids 7 days after treatment (Tang et al., 2002).
Neem azal T/S was most effective along with Decis and Karate against cereal aphids, Rhopalosiphum padi and Metopolophium dirhodum on wheat plants in green house conditions (Sallam et al., 2009). Spray of neem extract caused more than 95 (Percent) mortality of R. padi on barley (Sengonca and Bruggen, 1991). On the basis of cumulative insect days, except NSCE all the neem preparations produced comparable results to imidacloprid, under field conditions. The difference in the bio-efficacy of NLE field and lab studies may be due to the variation in the environmental conditions of these experiments as suggested by Lowery et al. (1993). Moreover pungent smell may also be the reason for low aphid population of NLE treated plots.
Lowery et al. (1993) reported that NSO and NSE treatments were as effective as the botanical pyrtherum for control of aphids on pepper and strawberry. According to Melesse and Singh (2012), NSKE proved better than all other treatments against pea aphid, Acyrthosiphon pisum and can be used for the management of pea aphid. Application of 5 (Percent) NSKE controlled the mustard aphid, Lipaphis erysimi to 13 aphids per plant on treated plots than 40 aphids per plant on untreated plots (Sanjeev and Singh, 2008).
The population of mummified aphids was very low in imidacloprid treated plots and maximum, in plots treated as a control. The comparison of the cumulative insect days reflected no or low (as in NSO-ethanol treatment) significant negative impact on aphid parasitism in plots treated with neem as compared to control. In an earlier study, Tang et al. (2002) found similar emergence of parasitoids from neem seed extract (Neemix) treated and untreated citrus brown aphids and concluded that application neem extract had a little impact on the survival and development of aphid parasitoids. There was no significant difference in the cumulative insect days in plots treated with neem as compared to control for lady bird beetles, syrphid fly larvae and green lace wing larvae. Many previous findings support the safety of neem based insecticide formulations towards predators.
Eisnenlohr et al. (1992) reported that the number of syrphid fly larvae in the field was not reduced after spraying of neem Azal-F on peach trees infested by Myzus persicae. Similarly Neemix was found to have little or no impact on lady bird beetles, parasitic wasps, spiders and predatory mites (Hoelmer et al.,1990; Stark et al., 1990). Kaethner (1991) used AZT-VR-K (1000 ppm) and a mixture of this product with NO (250-3000 ppm) on broad spectrum predator Chrysoperla carnea in the laboratory and semi-field trials. The products had no toxicity on eggs, larvae, adults and fecundity of the preadator. Similarly, Vogt (1993) was also unable to find the significant influence of neem-Azal-F on larvae of the lacewing in field trials. The neem products must be ingested to be effective, therefore insects, which feed on plant tissues, are affected by the extract and those which feed on other insects rarely contact lethal concentrations, which may lead to their insensitivity to the neem extracts.
The compatibility of neem formulations with beneficial insects of wheat is especially important to use them in conjunction with parasitoids and predators for management of wheat aphids. Maximum increase in the yield was observed NSKE (5 (Percent) treated plots followed by imidacloprid. Whereas application of imidacloprid resulted in maximum CBR (1:1:34) followed by that of NSKE 5 (Percent) (1:1.31), which reflects that imidacloprid is cheap as compared to neem extract. But if the additional cost of loss of beneficial insects and environmental risks posed by the application of insecticides is considered, the CBR of neem seed kernel extract may be regarded comparable to that of imidacloprid.
In conclusion, the effectiveness of both neem seed extracts and oils against English grain aphid. In field trials NSO-expeller proved as effective as imidacloprid against wheat aphids. Wheat yield was maximum in NSKE treated plots, which in-turn yielded highest CBR among all the neem preparations. Although CBR of NSKE was less as compared to imidacloprid, yet keeping in mind safety towards natural enemies and environment it may considered as a promising substitute of synthetic insecticides to control wheat aphids.
These studies were completed with the financial help of PMAS-Arid Agriculture University, Rawalpindi under the project grant entitled, "Exploration of pesticidal effect of different neem products against wheat aphids", which is highly acknowledged.
Aheer, G.M., A. Ali and M. Ahmad, 2008. Abiotic factors effect on population fluctuation of alate aphids in wheat. J. Agric. Res., 46:367-371
Akhtar, N. and Y. Mujahid, 2006. Patterns of resistance to Schizaphis graminum (Rondani) among rain fed national uniform wheat varieties. Pak. J. Zool., 38: 153-157
Basedow, T., H.R. Ossiewatsch, J.A. Bernal Vega, S. Kollmann, H.A.F. El Shafie and C.M.Y. Nicol, 2002. Control of aphids and whiteflies (Homoptera: Aphididae and Aleyrodidae) with different neem preparations in laboratory, greenhouse and field: effects and limitations. J. Plant Dis. Prot., 109: 612-623
Caroline, C., 2001. Insecticide Factsheet/Imidacloprid, Northwest Coalition for Alternatives to Pesticides (NCAP). J. Pestic. Reform., 21: 15-21
Charmaine Lloyd, A.C., T. Menon and K. Umamaheshwari, 2005.Anticandidal activity of Azadirachta indica. Ind. J. Pharmacol., 37:386-389
Eisnenlohr, K., A. L. Domange, C. Lenfant and B. Sauphanor, 1992. Effect of neem Azal-F on the aphids and beneficial insects in peasch orchards in France. In: Kleeberg, and H. Giessen (eds.). Proc. 1s tWorksh. Practice Oriented Results on Use and Prodcution of Neem- Ingredients, pp: 27-40. Druck and Graphics Gahukar, R.T., 2000. Use of neem products in cotton pest management. Int.J. Pest. Manage., 46: 149-160
GOP, 2008. Agricultural Statistics of Pakistan. Ministry of Food, Agriculture and Livestock (Economic Wing), Government of Pakistan, Islamabad, Pakistan Farooq, M., K. Jabran, Z.A. Cheema, A. Wahid and K.H.M. Siddique, 2011. The role of allelopathy in agricultural pest management. Pest Manage. Sci., 67: 493-506
Hoelmer, K.A., L.S. Osborne and R.K. Yokomi, 1990. Effects of neem extracts on beneficial insects in greenhouse culture. In: Neem's Potential in Pest Management Programs, pp: 100-105. Locke, J.C. and R.H. Lawson (eds.). U.S. Dep. Res. Serv. 86
Kaethner, M., 1991. No side effects of neem extracts on the aphidophagous predators Chrysoperla carnea (Steph.) and Coccinella septempunctata L. Anzeiger tur schad lings kunde, Pflanzenschutz, Umwelt Schutz, 64: 97-99
Khalequzzaman, M. and J. Nahar, 2008. Relative toxicity of some insecticides and azadirachtin against four crop infesting aphid species. Univ. J. Zool. Rajshahi Univ., 27: 31-34
Kiechefer, R.W. and J.L. Gellener, 1992. Yield losses in winter wheat caused by low- density cereal aphid poplations. Agron. J., 84: 180
Liang, G., W. Chen and T.X. Liu, 2003. Effects of three neem-based insecticides on diamondback moth (Lepidoptera: Plutellidae). Crop Prot., 22: 333-340
Liu, S.Y., R.L. Stoltz and Z.Z. Niu, 1986. Damage to wheat by Macrosiphum avenae in Northwest China. J. Econ. Entomol., 79:688-699
Lowery, D.T., M.B. Isman, and N.L. Brard, 1993. Laboratory and field evaluation of neem for the control of aphids (Homoptera: Aphididae). J. Econ. Entomol., 86: 864-870
Melesse, T. and S.K. Singh, 2012. Effect of climatic factors on pea aphid, Acyrthosiphon pisum Harris (Homoptera:Aphididae) population and its Management through planting dates and biopesticides in field pea (Pisum sativum L.). J. Agric. Tech., 8: 125-132
Musabyimana, T., R.C. Saxena, E.W. Kairu, C.P.K.O. Ogol and Z.R. Khan, 2001. Effects of Neem Seed Derivatives on Behavioral and Physiological Responses of the Cosmopolites sordidus (Coleoptera: Curculionidae). J. Econ. Entomol., 94: 449-454
Rashid, M.M., M.K. Khattak and K. Abdullah, 2012. Residual toxicity and biological effects of neem (Azadirachta indica) oil against cotton mealy bug, Phenacoccus solenopsis Tinsley (Sternorrhyncha: Pseudococcidae). Pak. J. Zool., 44: 837-843
Rossing, W.A.H., R.A. Daaman and M.J.W. Jansen, 1994. Uncertainty analysis applied to supervised control of aphids and brown rust in winter wheat. Part2. Relative importance of different components of uncertainty. Agris. Sys., 44: 449-460
Ruppel, R.F., 1983. Cumulative insect-days as an index of crop protection.J. Econ. Entomol., 76: 375-377
Russel, R.M., J.L. Robertson and N.E. Savin, 1977. POLO: A new computer program for probit analysis. Bull. Entomol. Soc., 23: 209-213
Sallam, A.A., C. Volkmar and N.E. El-Wakeil, 2009. Effectiveness of different bio-rational insecticides applied on wheat plants to control cereal aphids. J. Plant Dis. Prot., 116: 283-287
Sanjeev, R. and N. Singh, 2008. Field efficacy of eco-friendly pesticides against mustard aphid Lipaphis erysimi (Kalt.) on mustard. Environ. Ecol., 26: 1831-1834
Satti, A.A., M.E. Ellaithy and A.E. Mohamed, 2010. Insecticidal activities of neem (Azadirachta indica A. Juss) seeds under laboratory and field conditions as affected by different storage durations. Agric. Biol. J. N. Amer., 1: 1001-1008
Schmutterer, H., 1995. The Neem Tree Source of Unique Natural Products for IPM, Medicine, Industry and Other Purposes, VCH, Publication New York, USA
Schmutterer, H. and R.P. Singh, 2002. List of insect pests susceptible to neem products. In: The Neem Tree Azadirachta indica A. Juss. and other Meliaceous Plants. pp: 411-456. Schmutterer, H. and Weinhiem (eds). VCH Publications, Germany
Sengonca, C. and K.U. Bruggen, 1991. Untersuchungen uber die Wirkung wassriger Extrakte aus Quassia amara (L.) auf Getreideblattlause. J. Appl. Entomol., 112: 211-215
Senthil Nathan, S., K. Kalaivani, K. Murugan and P.G. Chung, 2005. The toxicity and physiological effect of neem limonoids on Cnaphalocrocis medinalis (Guene'e), the rice leaffolder. Pest. Biochem. Physiol., 81: 113-122
Shafeek, A., R.P. Jaya Prasanthi, G. Hariprasad Reddy, C.S. Chetty and G.Rajarami Reddy, 2004. Alterations in acetylcholinesterase and electrical activity in the nervous system of cockroach exposed to the neem derivative, azadirachtin. Ecotoxicol. Environ. Saf., 59: 205-208
Singh, R.P., C. Devakumar and S. Dhingra, 1988. Activity of Neem (Azadirachta indica A Juss) seed kernel extracts against the Mustard Aphid, Lipaphis erysimi. Phytoparasitica, 16: 225-230
Stark, J.D., R.I. Vargas and T.Y. Wong, 1990. Effects of neem seed extracts on tephritid fruit flies (Diptera: Tephritidae) and their parasitoids in Hawaii. ARSUSDA. Beitsville Md.: The Service, 86: 106-112
Stark, J.D. and J.F. Walter, 1995. Neem oil and neem oil components affect the efficacy of commercial neem insecticides. J. Agric. Food Chem.,43: 507-512
Steel, R.G.D., J.H. Torrie and D.A. Dickey, 1996. Principles and Procedures of Statistics: A Biometric Approach, 3rd edition. WCB Mc Graw Hill Companies, Inc., USA
Tang, Y.Q., A.A. Weathersbee and R.T. Mayer, 2002. Effect of neem seed extract on the brown citrus aphid (Homoptera: Aphididae) and its parasitoid Lysiphlebus testaceipes (Hymenoptera: Aphidiidae). Environ. Entomol., 31: 172-176
Trdan, S. and L. Mileroj, 1999. The cereal aphid (Sitobion avenae F.), wheat pest. Sodobno-Kmetijstvo, 32: 119-128
Vogt, H., 1993. Einsatz von Niempraparaten gegen Adoxophyes orana F.V.R. und Untersuchungen zu Nebenwirkungen. In: 6th Intern. Erfahrungsaust. uber Forschungserg. zum Okologischen Obstbau,pp: 51-55. LVWO, Weinsberg
Zeb, Q., H. Badshah, H. Ali, R.A. Shah and M. Rehman, 2011. Population of aphids on different varieties/lines of wheat and their effect on yield and thousands grain weight. Sarhad J. Agric., 27: 443-445
To cite this paper: Aziz, M.A., M. Ahmad, M.F. Nasir and M. Naeem, 2013. Efficacy of different neem (Azadirachta indica) products in comparison with imidacloprid against english grain aphid (Sitobion avenae) on wheat. Int. J. Agric. Biol., 15: 279-284
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|Author:||Aziz, Muhammad Asif; Ahmad, Munir; Nasir, Muhammad Farooq; Naeem, Muhammad|
|Publication:||International Journal of Agriculture and Biology|
|Date:||Apr 30, 2013|
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