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Research Article
 

Chronic Activity of Plant Volatiles Essential Oils in Management of Rice Weevil Sitophilus oryzae (Coleoptera: Curculionidae)



Bhuwan Bhaskar Mishra, S.P. Tripathi and C.P.M. Tripathi
 
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ABSTRACT

Stored food faces severe damage due to infestation by insects. The essential oils extracted from leaves of Aegle marmelos, Mentha arvensis, peels of Citrus reticulata and clove of Syzygium aromaticum by hydrodistillation method were screened as fumigant for chronic activity against rice weevil Sitophilus oryzae (Coleoptera: Curculionidae) in laboratory assay. All four essential oils showed chronic activity in a dose dependent manner. Fumigation with sub-lethal concentration of essential oils significantly (p<0.01) reduced oviposition capsity and exhibited ovicidal activity. Highest reduction in oviposition (35.66%) and feeding deterrence index (74.52%) observed in A. marmelos essential oils against S. oryzae in comparison to control groups. These studies showed strong insecticidal activity of all four essential oils and its potential role as a fumigant against S. oryzae. From this study it is concluded that these essential oils have potential for application in Insect Pest Management programs for stored-grain insect pests because of its fumigant action.

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Bhuwan Bhaskar Mishra, S.P. Tripathi and C.P.M. Tripathi, 2014. Chronic Activity of Plant Volatiles Essential Oils in Management of Rice Weevil Sitophilus oryzae (Coleoptera: Curculionidae). Journal of Entomology, 11: 78-86.

DOI: 10.3923/je.2014.78.86

URL: https://scialert.net/abstract/?doi=je.2014.78.86
 
Received: July 09, 2013; Accepted: November 18, 2013; Published: March 08, 2014



INTRODUCTION

Sitophilus oryzae (Coleoptera: Curculionidae) is a major pest of stored-grain products which occurs worldwide (Park et al., 2003; Athanassiou et al., 2008; Derbalah et al., 2012). Its local name is “Ghun” and commonly found in humid climatic conditions in the sub-tropical regions. The progeny production rate of S. oryzae is so high. The fourth instars larvae are highly active in rainy season and cause very high infestation.

The damage to stored-grains causes more economic loss of total world-wide production annually (Via, 1999; Weston and Rattlingourd, 2000). According to an estimate, the overall damage caused by stored-grain insect pests was 10-40% loss in temperate regions and tropical regions (Matthews, 1993). For control of S. oryzae many chemical fumigants and contact synthetic insecticides are commonly used to prevent the loss of stored products throughout the world. These chemical pesticides are still most effective against insect infestation but their repeated use has disrupted biological control by natural enemies and led to outbreaks of other insect species and sometimes resulted in the development of pest resistance (Ignatowicz, 1999; Zeng, 1999). Besides this chemical pesticides also play negative role in ozone depletion, environmental pollution and toxicity to non-target organisms (Zhang and Van Epenhuijsen, 2004).

To overcome this adverse impact on environment and human beings alternatives of chemical pesticides are being searched. Therefore, it is urgent need to develop certain insecticides which should be ecologically safe, biodegradable and cause no toxicity to non-target animals. Botanical pesticides have high insecticidal activity against insect pests that check its infestation stage (Isman, 2000; Sahaf and Moharamipour, 2009; Ikbal et al., 2007). The insecticidal activity of essential oils against different stored-product pests has been evaluated and is environmentally compatible (Shaaya et al., 1991; Sarac and Tunc, 1995; Aslan et al., 2005; Ayvaz et al., 2007; Oparaeke and Kuhiep, 2006; Asmanizar et al., 2012). In present time, botanical insecticides in the form of essential oils presently constitute 1% of the world insecticide market (Rozman et al., 2007).

The essential oils of Aegle marmelos (Rutaceae), Citrus reticulata (Rutaceae), Mentha arvensis (Laminaceae) and Syzygium aromaticum (Myrtaceae) are known to exhibit antifungal, antibacterial, antimicrobial properties (Jeeva et al., 2007; Koochak et al., 2010; Kingston et al., 2009). Their repellent and toxic effect against S. oryzae has already been determined and finds their lethal concentration values (Mishra and Tripathi, 2011; Mishra et al., 2011, 2012, 2013). This study was undertaken to evaluate the bioefficacy of the essential oils from A. marmelos, M. arvensis, C. reticulata and S. aromaticum against S. oryzae in chronic exposure at sub-lethal concentration.

MATERIALS AND METHODS

Extraction of essential oils: For plant collection and extraction of essential oils, leaves of A. marmelos, M. arvensis, peels of C. reticulata were collected and cloves of S. aromaticum was purchase from the local area of Gorakhpur district of Uttar Pradesh, India. The specimens were identified and authenticated by Department of Botany, D. D. U. Gorakhpur University, Gorakhpur. The buds and leaves (1 kg of each) were dried in the absence of sun light at room temperature (30±5°C) and grounded using a domestic mixer. The essential oils were extracted with distilled water by hydro-distillation using a modified Clevenger apparatus. Distillation was done continuously for 5 h to yield essential oils (1-1.5 mL approximately). Anhydrous sodium sulphate was used to remove water after extraction. The superior phase was collected from the condenser in glass containers and stored in appendorff tube at 5°C until their use for further experiments.

Insect rearing: Rice weevils S. oryzae were used to examine the activity of essential oils. For experiments adults of insects were taken from laboratory stock cultures at 28±2°C, 75±5% RH and at a photoperiod of 10:14 (L:D). The adults were reared on grains and flours of rice (Oryza sativa) and wheat (Triticum aestivum) at 12-13% moisture content. The newly born 10 days old unsexed adult weevils were used to determine the insecticidal property of essential oils.

Effect of essential oils on oviposition capability and hatchability of eggs: The effect of A. marmelos, C. reticulata, M. arvensis and S. aromaticum essential oils on oviposition capability and hatchability of eggs was tested against S. oryzae by fumigation. Ten adults taken from the laboratory culture (1-2 week old) were placed in 1 g of wheat flour and grain in glass petri dish (height 15 mmxradius 45 mm). Flour and grain was spread uniformly along the whole surface of the petri dish. A paper strip (2 cm2) treated with 40, 60 and 80% sub-lethal concentration of 24 h LC50 of essential oils in acetone was pasted on the inner surface of the cover of each petri dish. Another paper strip (2 cm2) was treated with absolute acetone only used as control. All the closed petri dishes were kept in dark and six replicates were set for each concentration. After 72 h of fumigation, the treated adults of S. oryzae were transferred to fresh petri dish having fresh wheat flour and grain. After 7 days of treatment, the adults of both stored-grain pests were removed and discarded. The number of the larvae hatched was counted for the treated as well as for control groups.

Hatchability was calculated as percentage:

Image for - Chronic Activity of Plant Volatiles Essential Oils in Management of Rice Weevil 
  Sitophilus oryzae (Coleoptera: Curculionidae)

C = No. of larvae in control
T = No. of larvae in test

Determination of chronic toxicity of essential oils: The chronic toxic activity of A. marmelos, C. reticulata, M. arvensis and S. aromaticum essential oils was tested against adults of S. oryzae by contraction method with two sub-lethal concentrations. Whatman No. 1 filter papers were cut according to the shape and size of petri dishes and treated with sub-lethal concentrations of essential oils prepared in acetone (30 and 60% of 24 h LC50) by using micropipette. The treated filter papers were dried to evaporate the solvent completely. The treated filter paper placed at the bottom in glass petri dish (height 15 mmxradius 45 mm). Ten adults taken from the laboratory culture (1-2 week old) were placed with 1 g of wheat flour and grain in petri dish. Flour and grains were spread uniformly along the whole surface of the petri dish. All the closed petri dishes were kept in dark and six replicates were set for each concentration. After 30 days per cent grains damage by stored-grain insect pests were recorded. The adults surviving after treatment were used for experiments.

Data analysis: Correlation and linear regression analysis were conducted to define all dose-response relationships (Sokal and Rohlf, 1973). Analysis of variance was performed to test the equality of regression coefficient (Sokal and Rohlf, 1973).

RESULTS

The essential oils significantly (p<0.01) inhibited oviposition capacity of S. oryzae at three sub-lethal concentrations compared to control. The maximum oviposition inhibitory activity of A. marmelos, C. reticulata, M. arvensis and S. aromaticum essential oils against adults of S. oryzae was 35.66, 53.31, 44.90 and 43.31% at 80% sub-lethal concentration of 24 h LC50, respectively (Table 1).

The hatchability percentage of A. marmelos, C. reticulata, M. arvensis and S. aromaticum essential oils was 47.41, 30.45, 38.05 and 39.55% reduced in compared to control at 80% of 24 h LC50 against S. oryzae, respectively (Table 1).

The essential oils of A. marmelos, C. reticulata, M. arvensis and S. aromaticum caused less damage to the grains by adults of stored-grain insect pest S. oryzae by fumigation action. The percent grains infection was reduced by A. marmelos, C. reticulata, M. arvensis and S. aromaticum essential oils against S. oryzae was 74.520±0.82, 66.23±0.56, 57.30±0.61 and 59.56±0.48 at 60% sub-lethal concentration of 24 h LC50 (Table 2).

The decrease in oviposition potential of S. oryzae (F = 222.440; 102.425; 260.782 and 202.163) (df = 3.20; p<0.01) was significant when fumigated with A. marmelos, C. reticulata, M. arvensis and S. aromaticum essential oils, respectively (Table 3).

The regression analysis indicated that per cent damage grain reduction of adults of S. oryzae by essential oils showed a significant negative correlation (df = 2.15; p<0.01) with concentration when fumigated with A. marmelos (F = 606.31), C. reticulata (F = 517.54), M. arvensis (F = 408.75) and S. aromaticum (F = 488.36) essential oil (Table 3).

Table 1: Effect of fumigation of Aegle marmelos, Citrus reticulata, Mentha arvensis and Syzygium aromaticum essential oils on oviposition of stored-grain insect pest Sitophilus oryzae
Image for - Chronic Activity of Plant Volatiles Essential Oils in Management of Rice Weevil 
  Sitophilus oryzae (Coleoptera: Curculionidae)
aHatchability percentage was calculated as 100(C-T)/(C+T), where C and T represent the No. of eggs/larvae produced in the control and in the test, respectively

Table 2: Effect of fumigation of Aegle marmelos, Citrus reticulata, Mentha arvensis and Syzygium aromaticum essential oils on damage caused by stored-grain insect pest Sitophilus oryzae
Image for - Chronic Activity of Plant Volatiles Essential Oils in Management of Rice Weevil 
  Sitophilus oryzae (Coleoptera: Curculionidae)

Table 3: Regression parameters of sub lethal and chronic activity of A. marmelos, C. reticulata, M. arvensis and S. aromaticum essential oils on stored-grain insect pest S. oryzae by fumigation method
Image for - Chronic Activity of Plant Volatiles Essential Oils in Management of Rice Weevil 
  Sitophilus oryzae (Coleoptera: Curculionidae)
FDI (%): Feeding deterrence index. *F values were significant at all probability levels (90, 95 and 99%), *df = 3,20; **df = 2, 15

Analysis of variance revealed that A. marmelos essential oil had strong chronic activity with sub-lethal concentration against rice weevil in comparison to other essential oils (Table 3).

Image for - Chronic Activity of Plant Volatiles Essential Oils in Management of Rice Weevil 
  Sitophilus oryzae (Coleoptera: Curculionidae)
Fig. 1: Percent hatchability and percent grain reduction assay when Sitophilus oryzae adults were fumigated with essential oils by chronic exposure

DISCUSSION

This insecticidal activity in essential oils are may be due to presence of volatile chemicals present in essential oils having different functional groups which persist for longer time if used against stored grain insects in closed chambers. On an average each essential oils extract has shown 60-75% oviposition and damaging food reduction. This high oviposition inhibition and feeding deterrence in all four essential oils was due to volatile components present in essential oils available in leaves, peels and buds.

In GC-MS analysis, the essential oils of A. marmelos, C. reticulata, M. arvensis and S. aromaticum show different chemical components. The leaf essential oil of A. marmelos contain 15 compounds, in all of this limonene was the main constituent (Kaur et al., 2006). The Citrus genus extracts are monocyclic monoterpenoides and the main constituents are d-limonene show insecticidal activity (Karr and Coats, 1988). The major constituents reported from essential oils of M. arvensis are L-menthone (29.41%), menthol (21.33%), isomenthone (10.80%), eucalyptol (6.91%), neo-menthol (4.70%), cis-piperitone oxide (3.62%), linalool (2.20%), thymol (1.60%), di-Limonene (1.47%) and a-Phellandrene (3.20%) (Mishra et al., 2012). In clove essential oil of S. aromaticum, eugenol, caryophyllene, eugenol acetate and alpha-humelene are present and in all of these, eugenol is the main constituent (Viuda-Martos et al., 2007).

When adult weevils were exposed to sub-lethal dose of essential oils; these have shown significantly oviposition inhibition in female insects and block the emergence of F1 individuals from exposed eggs. From the result it was found that oviposition inhibition in S. oryzae was dose and time dependent because when the concentration of essential oils increased oviposition inhibition in adults was also increased.

It is clear from the results section that all the essential oils showed a significant (p<0.01) reduction in oviposition and chronic toxic activity against adults of S. oryzae compared to control. Maximum oviposition inhibition and chronic toxic activity was observed by A. marmelos against adults of S. oryzae (Table 1, 2).

The present findings are similar to the observations of Kumar et al. (2008) who tested insecticidal activity of A. marmelos essential oil against four stored-grain insect pests and found significant reduction in oviposition and chronic activity against four stored-grain insect pests. The monoterpenoids are present in A. marmelos essential oil and they inhibit reproduction of stored insects at several steps of their life cycles. Sur et al. (1999) reported anti spermatogenic acitivity of ethanolic extract of A. marmelos leaves in rats. Similarly, Remya et al. (2009) studied the effect of ethanol extracts of leaves of A. marmelos for their in-vitro effect on sperm motility and suggested that extracts had a considerable effect on the motility of sperms.

In the present investigation, C. reticulata essential oil also showed the reduction in adult emergence which could either is due to the egg mortality or larval mortality or even reduction in hatching of the eggs. Similarly, Zewde and Jembere (2010) evaluated the orange peel C. sinensis as a source of protectant against Zabrotes subfasciatus (Coleoptera: Bruchidae) and found significant reduction in progeny emergence of Z. subfasciatus. The current findings are supported with to the results of Tripathi et al. (2003) who has also reported oviposition reduction (94.5%) effects of orange peel oil against T. castaneum.

Mentha oil is lipophilic in nature and accumulates with lipids, it had a strong morphogenic effect acting by fumigation and disrupting adult development. The reduction in oviposition and adult emergance may be due to suffocation and inhibition of various biosynthesis processes of the insects at developmental stages. Mesbah et al. (2006) reported that all the efficiency tested essential oils acted principally as insect growth inhibitors causing disruption of insect development and abnormal adults that were lead finally to death.

Bhat and Kempraj (2009) found that the hatchability of the eggs was affected by the presence of leaf and buds of clove oils. The present investigation was also supported to the result of Sharma and Meshram (2006) that evaluated insecticidal activity of essential oils of Acorus calamus (Acoraceae) and S. aromaticum (Myrtaceae) against S. oryzae as seed protector. The use of both essential oils exhibited inhibition of F1 progeny from 61.08-91.52%.

Recently, Jeyasankar et al. (2010) tested the antifeedent and growth inhibitory activities of Syzygium lineare leaves against fourth instars larvae of Spodoptera litura and found that high pupal, adult deformities and decreased adult emergence of S. litura. Ho et al. (1994) investigated the biological activity of S. aromaticum oil against stored-products pests. They found that this oil suppress progeny development of T. castaneum with isoeugenol being particularly active.

CONCLUSION

The present study indicates that after fumigation of the essential oils obtained from A. marmelos, C. reticulata, M. arvensis and S. aromaticum reduce the oviposition of S. oryzae. Observation further reveal that per cent infestation rate of S. oryzae is also drastically affected. Therefore, the essential oils obtained from the aforesaid plants products can be used to protect stored-grains from the infestation of rice weevil.

REFERENCES

1:  Aslan, I., O. Calmasur, F. Sahin and O. Caglar, 2005. Insecticidal effects of essential plant oils against Ephestia kuehniella (Zell.), Lasioderma serricorne (F.) and Sitophilus granarius (L.). J. Plant Dis. Prot., 112: 257-267.
Direct Link  |  

2:  Asmanizar, A. Djamin and A.B. Idris, 2012. Evaluation of Jatropha curcas and Annona muricata seed crude extracts against Sitophilus zeamais infesting stored rice. J. Entomol., 9: 13-22.
CrossRef  |  Direct Link  |  

3:  Athanassiou, C.G., N.G. Kavallieratos, B.J. Vayias and E.C. Panoussakis, 2008. Influence of grain type on the susceptibility of different Sitophilus oryzae (L.) populations, obtained from different rearing media, to three diatomaceous earth formulations. J. Stored Prod. Res., 44: 279-284.
CrossRef  |  Direct Link  |  

4:  Ayvaz, A., S. Albayrak and A.┼×. Tun├žbilek, 2007. Inherited sterility in mediterranean flour moth Ephestia kuehniella zeller (Lepidoptera: Pyralidae): effect of gamma radiation on insect fecundity, fertility and developmental period. J. Stored Prod. Res., 43: 234-239.
CrossRef  |  Direct Link  |  

5:  Bhat, S.K. and V. Kempraj, 2009. Biocidal potential of clove oils against Aedes albopictus-a comparative study. Afr. J. Biotechnol., 8: 6933-6937.
Direct Link  |  

6:  Ikbal, C., B.H.K. Monia and B.H.M. Habib, 2007. Development perturbation of cotton leave noctuid with green cestrum extracts. J. Entomol., 4: 121-128.
CrossRef  |  Direct Link  |  

7:  Derbalah, A.S., A.M. Hamza and A.A. Gazzy, 2012. Efficacy and safety of some plant extracts as alternatives for Sitophilus oryzae control in rice grains. J. Entomol., 9: 57-67.
CrossRef  |  Direct Link  |  

8:  Ho, S.H., L.P.L. Cheng, K.Y. Sim and H.T.W. Tan, 1994. Potential of cloves (Syzygium aromaticum (L.) Merr. and Perry as a grain protectant against Tribolium castaneum (Herbst) and Sitophilus zeamais Motsch. Postharvest Biol. Technol., 4: 179-183.
CrossRef  |  

9:  Ignatowicz, S., 1999. Cases of phosphine resistance for grain weevil, Sitophilus granarius found in Poland. Proceedings of the 7th International Working Conference on Stored-Product Protection, October 14-19, 1998, Beijing, China, pp: 625-630
Direct Link  |  

10:  Isman, M.B., 2000. Plant essential oils for pest and disease management. Crop Protect., 19: 603-608.
CrossRef  |  Direct Link  |  

11:  Jeeva, S., C. Kingston, S. Kiruba and D. Kannan, 2007. Scared Forests: Treasure Trove of Medicinal Plants: A Case Study from South Travancore. In: Indian Folk Medicine, Trivedi, P.C. (Ed.). Pointer Publishers, Jaipur, India, ISBN: 9788171325214, pp: 262-274

12:  Jeyasankar, A., N. Raja and S. Ignacimuthu, 2010. Antifeedant and growth inhibitory activities of Syzygium lineare Wall (Myrtaceae) against Spodoptera litura Fab. (Lepidoptera: Noctuidae). Cur. Res. J. Biol. Sci., 2: 173-177.
Direct Link  |  

13:  Karr, L.L. and J.R. Coats, 1988. Insecticidal properties of d-limonene. J. Pesticide Sci., 13: 287-290.
Direct Link  |  

14:  Kaur, H.P., S.N. Garg, K.V. Sashidhara, A. Yadav, A.A. Naqvi and S.P.S. Khanuja, 2006. Chemical composition of the essential oil of the twigs and leaves of Aegle marmelos (L.) Correa. J. Essent. Oil Res., 18: 288-289.
CrossRef  |  Direct Link  |  

15:  Kingston, C., S. Jeeva, G.M. Jeeva, S. Kiruba, B.P. Mishra and D. Kannan, 2009. Indigenous knowledge of using medicinal plants in treating skin diseases in Kanyakumari district, Southern India. Indian J. Tradit. Knowledge, 8: 196-200.
Direct Link  |  

16:  Koochak, H., S.M. Seyyednejad and H. Motamedi, 2010. Preliminary study on the antibacterial activity of some medicinal plants of Khuzestan (Iran). Asian Pacific J. Trop. Med., 3: 180-184.
CrossRef  |  

17:  Kumar, R., A. Kumar, C.S. Prasa, N.K. Dubey and R. Samant, 2008. Insecticidal activity Aegle marmelos (L.) Correa essential oil against four stored grain insect pests. Int. J. Food Saf., 10: 39-49.
Direct Link  |  

18:  Matthews, G.A., 1993. Insecticide Application in Stores. In: Application Technology for Crop Protection, Matthews, G.A. and E.C. Hislop (Eds.). CAB International, Wallingford, UK., pp: 305-315

19:  Mesbah, H.A., A.K. Mourad and A.Z. Rokaia, 2006. Efficacy of some plant oils alone and/or combined with different insecticides on the cotton leaf-worm Spodoptera littoralis (Boisd.) (Lepidoptera: Noctuidae) in Egypt. Common. Agric. appl. Boil. Sci., 71: 305-328.
Direct Link  |  

20:  Mishra, B.B. and S.P. Tripathi, 2011. Repellent activity of plant derived essential oils against Sitophilous oryzae (Linnaeus) and Tribolium castaneum (herbst). Singapore J. Sci. Res., 1: 173-178.
CrossRef  |  Direct Link  |  

21:  Mishra, B.B., S.P. Tripathi and C.P.M. Tripathi, 2011. Contact Toxicity of essential oil of Citrus reticulata fruits peels against stored grain pests Sitophilous oryzae (Linnaeus) and Tribolium casteneum (Herbst). World J. Zool., 6: 307-311.

22:  Mishra, B.B., S.P. Tripathi and C.P.M. Tripathi, 2012. Response of Tribolium castaneum (Coleoptera: Tenebrionidae) and Sitophilus oryzae (Coleoptera: Curculionidae) to potential insecticide derived from essential oil of Mentha arvensis leaves. Biol. Agric. Horticult.: Int. J. Sustain. Prod. Syst., 28: 34-40.
CrossRef  |  Direct Link  |  

23:  Mishra, B.B., S.P. Tripathi and C.P.M. Tripathi, 2013. Bioactivity of two plant derived essential oils against the Rice weevils Sitophilus oryzae (L.) (Coleoptera: Curculionidae). Proc. Natl. Acad. Sci. India Sect. B: Biol. Sci., 83: 171-175.
CrossRef  |  Direct Link  |  

24:  Oparaeke, A.M. and G.C. Kuhiep, 2006. Toxicity of powders from indigenous plants against Sitophilus zeamais motsch on stored maize grains. J. Entomol., 3: 216-221.
CrossRef  |  Direct Link  |  

25:  Park, I.K., S.G. Lee, D.H. Choi, J.D. Park and Y.J. Ahn, 2003. Insecticidal activities of constituents identified in the essential oil from leaves of Chamaecyparis obtusa against Callosobruchus chinensis (L.) and Sitophilus oryzae (L.) J. Stored Prod. Res., 39: 375-384.
CrossRef  |  

26:  Remya, M., R.C. Sharma, H. Shoaib, J.R.U. Asad and S. Swati, 2009. In vitro effect of Aegle marmelos on human sperm motility. J. Med. Plants Res., 3: 1137-1139.
Direct Link  |  

27:  Rozman, V., I. Kalinovic and Z. Korunic, 2007. Toxicity of naturally occurring compounds of Lamiaceae and Lauraceae to three stored-product insects. J. Stored Prod. Res., 43: 349-355.
CrossRef  |  Direct Link  |  

28:  Sahaf, B.Z. and S. Moharamipour, 2009. Comparative study on deterrency of Carum copticum C. B. Clarke and Vitex pseudo-negundo (Hausskn.) Hand.-Mzt. essential oils on feeding behavior of Tribolium castaneum (Herbst). Iran. J. Med. Arom. Plants, 24: 385-395.
Direct Link  |  

29:  Sarac, A. and I. Tunc, 1995. Toxicity of essential oil vapours to stored-product insects. Zeitschrift fur Pflanzenkrankheiten und Pflanzenschutz, 102: 429-434.

30:  Shaaya, E., U. Ravid, N. Paster, B. Juven, U. Zisman and V. Pissarev, 1991. Insecticidal activity of essential oils against four major stored product insects. J. Chem. Ecol., 17: 499-504.

31:  Sharma, K. and N.M. Meshram, 2006. Bioactivity of essential oils from Acorus calamus Linn. and Syzygium aromaticum Linn. against Sitophilus oryzae Linn. in stored wheat. Biopesticide Int., 2: 144-152.

32:  Sokal, R.R. and F.J. Rohlf, 1973. Introduction to Biostatistics. W.H. Freeman and Co., San Francisco, Pages: 365

33:  Sur, T.K., S. Pandit and T. Pramanik, 1999. Antispermatogenic activity of leaves of Aegle marmelos, Corr. in albino rats: A preliminary report. Biomedicine, 19: 199-202.

34:  Tripathi, A.K., V. Prajapati, P.S. Khanuja and S. Kumar, 2003. Effect of d-limonene on three stored-product beetles. J. Econ. Entomol., 96: 990-995.
CrossRef  |  Direct Link  |  

35:  Via, S., 1999. Cannibalism facilitates the use of a novel environment in the flour beetle, Tribolium castaneum. Heredity, 82: 267-275.
CrossRef  |  

36:  Viuda-Martos, M., Y. Ruiz-Navajas, J. Fernandez-Lopez and J.A. Perez-Alvarez, 2007. Chemical composition of the essential oils obtained from some spices widely used in Mediterranean region. Acta Chimica Slovenica, 54: 921-926.
Direct Link  |  

37:  Weston, P.A. and P.L. Rattlingourd, 2000. Progeny production by Tribolium castaneum (Coleoptera: Tenebrionidae) and Oryzaephilus surinamensis (Coleoptera: Silvanidae) on maize previously infested by Sitotroga cerealella (Lepidoptera: Gelechiidae). J. Econ. Entoml., 93: 533-536.
CrossRef  |  PubMed  |  Direct Link  |  

38:  Zeng, L., 1999. Development and counter measures of phosphine resistance in stored grain insects in Guandong of China. Proceedings of 7th Inenational Working Conference on Stored-Product Protection, October 14-19, 1998, Beijing, China, pp: 642-647

39:  Zewde, D.K. and B. Jembere, 2010. Evaluation of orange peel Citrus sinensis (L) as a source of repellent, toxicant and protectant against Zabrotes subfasciatus (Coleoptera: Bruchidae). Momona Ethiop. J. Sci., 2: 61-75.
Direct Link  |  

40:  Zhang, Z. and C.W. Van Epenhuijsen, 2004. Improved envirosol fumigation methods for disinfesting export cut Xowers and foliage crops. New Zealand Institute for Crop and Food Research Limited, Palmerston North, New Zealand.

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