IJERD – International Journal of Environmental and Rural Development (2022) 13-1

Research article
erd

Toxicity of Plant Essential Oil from Khok Phutaka
Resources Protection Area, Khon Kaen Province Against
Storage Pest, Sitophilus oryzae
DUANGRAT THONGPHAK*
Entomology Section, Faculty of Agriculture, Khon Kaen University, Khon Kaen, Thailand
E-mail: duathg@kku.ac.th

PRAPAPORN PIANGSUWAN
Entomology Section, Faculty of Agriculture, Khon Kaen University, Khon Kaen, Thailand
Received 30 January 2022

Accepted 2 May 2022(*Corresponding Author)

Abstract Botanical insecticides may offer an alternative solution for pest control. The
objective was to test on the repellant, contact, and fumigant effect of the essential oils of 10
indigenous plants from Khok Phutaka Resources Protection Area, Khon Kaen Province
including Limnophila aromatica, Piper sarmentosum, Clausena harmandiana,
Streptocaulon juventas, Litsea glutinosa, Thunbergia laurifolia, Eupatorium odoratum,
Rothmannia wittii, Ficus altissima, Clausena harmandiana and Gymnopetalum integrifolim
to control the rice weevil, S. oryzae. The essential oils of plants were extracted by usinghydro-distillation method and then they were tested against rice grain weevil, S. oryzae forcontact, fumigant and repellent activities in laboratory condition. Adults of weevil weredifferent tested oil at the concentrations of 0, 25, 50, 75 and 100 percentage (w/v). The
maximum repellency action, 80% when L. glutinosa oil, at the concentrations of 100%(w/v) were applied for after 72 hours follow by L. aromatica (73.33%) at the concentrationsof 25% (w/v) were applied for after 2 hours. The fumigant and contact test of all 10
essential oils resulted in all lower rate mortality (less than 50%), at all the concentrations.
Keywords essential oil, Sitophilus oryzae, repellency, fumigant, contact,
Khok Phutaka Resources Protection Area

INTRODUCTION
The rice weevil, Sitophilus oryzae Linnaeus 1763 (Coleoptera: Curculionidae) is a serious andsevere insect pest of stored products (Park, 2003) and one of the most widespread and destructive
stored product pests of rice throughout the world. Treatment of rice with synthetic insecticides is
not recommended because of direct and indirect health hazards to humans. Plants are sources ofnatural insecticides that are produced to defend themselves against those insect pests. Many plants
are rich in secondary compounds with insecticidal activities. The several efforts have been focusedon the use of plant derived materials including essential oils as bio insecticides.
OBJECTIVE
The objective of this study was to screen plant oils of 10 indigenous plants from Khok Phutaka
Resources Protection Area, Khon Kaen Province as repellent contact and fumigant against adults ofrice weevil, S. oryzae.
METHODOLOGY
Insect RearingⒸ ISERD164

IJERD – International Journal of Environmental and Rural Development (2022) 13-1

Adults of S. oryzae were reared in the laboratory conditions at 25 ± 2ºC, 46.8 ± 5.0% R.H.
Approximately, 50 of S. oryzae adults were placed in 11×10×5 cm plastic containing 500 g of ricegrains. Colonies were reared on whole rice grains in plastic container. The insects were reared forseveral generations on rice. For the bioassays, the F1 generation of the adults from the rearing wasused.
Extraction of Essential Oil
Ten of indigenous plants were collected from Khok Phutaka Resources Protection Area, KhonKaen Province (Table 1). The essential oils of plants were extracted by using hydro-distillation
method.
Table 1 Plant essential oils used in the study
Scientific Name
Litsea glutinosa
Thunbergia laurifolia
Streptocaulon juventas Merr
Ficus altissima
Eupatorium odoratum L.
Rothmannia wittii
Clausena harmandiana
Gymnopetalum integrifolim Kurz.
Limnophila aromatica (Lam.) Merr.
Piper sarmentosum Roxb.

FamilyLauraceae
Acanthaceae
Asclepiadaceae
Moraceae
Asteraceae
Rubiaceae
Rutaceae
Cucurbitaceae
Plantaginaceae
Piperaceae

Plant usedLeaves
LeavesLeavesLeavesLeavesLeaves
LeavesLeavesWhole plant
LeavesRepellent Activity Bioassay
The repellency test was used the area preference method based on Lü and Ma (2015). The essential
oils of plants were diluted in acetone to prepare different concentrations (25, 50, 75 and 100%(w/v)). Pure acetone was used as the control. Each treatment was replicated five times. The numberof insects present on the control and treated regions were recorded to 1, 2, 3, 4, 5, 6, 12 and 24
hours after treatment. Mean number of insects present on the control (NC) and treated (NT) regionsduring the experiment were used to estimate the Percent Repellency (PR) which was equal to[NC/(NC+NT)] × 100 (Nerio et al., 2009).
Contact Toxicity Bioassay
The contact toxicity test was done by the used of impregnated filter paper test method modified
from Fournet et al. (1996). The essential oils of the plants were diluted in acetone to prepare four
different concentrations (25, 50, 75 and 100% (w/v)). Controls were treated with acetone alone.
Ten adults of S. Oryzae were released separately into each petri dish and covered with a lid. Fivereplicates of each treatment and control were set up. Mortality was recorded after 24, 48, and 72
hours. Mortality rate was estimated and corrected according to Abott’s formula (Abbott, 1925)
Fumigant Toxicity Bioassay
The fumigant toxicity test was conducted by using space trial test method based on Keita et al.
(2001). Series of dilutions of essential oils were prepared different concentrations (25, 50, 75 and100% (w/v)) using acetone as a solvent. Five replications of each treatment were set up. Controls
were maintained in the similar way with the solvent only. Mortality was recorded after 24, 48, and72 hours. Mortality rate was estimated and corrected according to Abott’s formula (Abbott, 1925).
Ⓒ ISERD

165

IJERD – International Journal of Environmental and Rural Development (2022) 13-1

RESULT AND DISCUSSION
Ten different plant oils were tested against the adults of Sitophilus oryzae at concentrations of 25,50, 75 and 100% (w/v) for repellent activity, contact toxicity and fumigant toxicity tests.
Repellent Activity Bioassay
In general, repellency increases with increase in concentration in the treatment. The result indicatedvariation among the essential oils tested. The Percent Repellency (PR) ranged from 23.33 to
80.00%. The maximum repellency action, 80% when L. glutinosa oil, at the concentrations of
100% (w/v) were applied for after 72 hours follow by L. aromatica (73.33%) at the concentrationsof 25% (w/v) were applied for after 2 hours (Fig. 1). Arshad et al. (2013) that tested the repellentsof guava leaf extracts found 20% (w/v) concentration of P. guajava was the one with the highest
repellent effects on S. oryzae with mean % repellent of 70.3% (class 4) might be attributed topresence of some aromatic monoterpenoids that are major constituents of family Mytaceae (Isman,2000) and this substance is a group of substances found in L. aromatica as well (Vairappan andNagappan, 2014).

Fig. 1 Comparison percent repellency (PR) of the 10 essential oils
with different concentration to Sitophilus oryzae adults
after exposure time using the area preference method
Contact Toxicity Bioassay
Mortality of S. oryzae varied from 0 to 30% after 24, 48, 72 hrs. of treated of 10 essential oils ofplants at 25, 50, 75 and 100 concentrations (w/v). These results demonstrate (Fig. 2) that theefficiency of the oils was directly related to concentration and exposure time. Oil from R. wittii was
the most efficient, causing 30% mortality at concentrations of 100% (w/v) in 72 h. The result
indicated that all concentrations are lower rate mortality. Some other studies have found different
result from this study such as Mattana et al. (2018) showed that the essential oil of P. sarmentosum
leaves showed strong contact and fumigant toxicity at 72 h against adults of S. oryzae. Differences
may be due to the collect from different seasons of the year, soil type and climate, among others
Fumigant Toxicity BioassayⒸ ISERD

166

IJERD – International Journal of Environmental and Rural Development (2022) 13-1

The result of fumigant toxicity (Fig. 3) showed that adult rice weevil exposure to the 10 essential
oil of plant different concentration had lower effect on mortality (less than 50%) except the oilfrom T. laurifolia was the most efficient, causing 56% mortality at 100% (w/v) concentration in 72
hr. Fumigant toxicity of the essential oils gradually increased with increasing exposure time andconcentration. Fang et al. (2010) reported that the essential oil of Carum carvi L. fruit was
insecticidal activity against the maize weevil and red flour beetle adults. Mishra et al. (2012)
reported that the essential oils of Syzygium aromaticum and Aegle marmelos have fumigation
toxicity against S. oryzae at 48 hours exposure were the LC50 values 15.3 and 16.1 µl respectively.

Fig. 2 Comparison contact effect of plant extracts with different concentration
to S. oryzae adults after exposure time using impregnated filter paper test

Fig. 3 Fumigant effect of plant extracts with different concentration
to S. oryzae adults after exposure time using space trial testⒸ ISERD

167

IJERD – International Journal of Environmental and Rural Development (2022) 13-1

CONCLUSION
The results obtained in this study demonstrate that the essential oils tested can be used to control
stored grain pests and to support further studies. The toxic effects of essential oils involve manyfactors, among which are the entry point of toxins, and which may have contact, fumigation, andrepellent effects. However, in the present study some of the plant oils did not show any mortality orshowed least mortality which might be due to the presence of weak volatile compounds. However,
the results of this study indicate that the essential oils might be useful for managing the insect pests
in storage especially S. oryzae.
ACKNOWLEDGEMENTS
This research was supported by the Program Management Unit for Human Resources &Institutional Development, Research and Innovation [grant number B05F630053] and the research
was a part of the Plant Genetic Project under The Royal Initiative of Her Royal Highness Princess
Maha Chakri Sirindhorn, Khon Kaen University [grant number 630000050102].
REFERENCES
Abbott, W.S. 1925. A method of computing the effectiveness insecticides. Journal Economic Entomology, 18(2), 265-267.
Akhtar, M., Arshad, M., Raza, M.B.A., Chaudhary, I.M., Iram, N., Akhtar, N. and Mahmood, T. 2013.
Repellent effects of certain plant extracts against rice weevil, Sitophilus oryzae L. (ColeopteraP;Curculionidae). International Journal of Applied Agricultural Research. 5 (1), 69-73.
Fang, R., Jiang, H.C., Wang, Y.X., Zhang, M.H., Liu, L.Z., Zhou, L., Du, S.S. and Deng, W.Z. 2010.
Insecticidal activity of essential oil of Carum carvi fruits from China and its main components against
two grain storage insects. Molecules, 15, 9391-9402.
Fournet, A., Arias, R.A. de, Charles, B. and Bruneton, J. 1996. Chemical constituents of essential oils ofmuña, Bolivian plants traditionally used as pesticides, and their insecticidal properties against Chagas'
disease vectors. Journal of Ethnophar Macology, 52, 145-149.
Isman, B.M. 2000. Plant essential oils for pest and disease management. Crop Protection. 19, 603- 608.
Keita, M.S., Vincent, C., Schmit, J.P., Arnason, T.J. and Belanger, A. 2001. Effecacy of oil of Ocimum
basilicum L. and O. gratissimum L. applied as an insecticidal fumigant and powder to control
Callosobruchus maculates (Fab.) (Coleoptera: Bruchidae). Journal of Stored Products Research. 37, 339349.
Lü, J. and Ma, D. 2015. Repellent and contact toxicity of alpinia officinarum rhizome extract against
lasioderma serricorne adults. PLoS ONE, 10 (8), e0135631.
Mattana, K., Vanichpakorn, Y. and Vanichpakorn, P. 2018. Chemical composition and toxicity of essential
oil from Piper sarmentosum leaves against Sitophilus oryzae. Khon Kaen Agriculture Journal, 46Supplement, 1, 189-194.
Mishra, B.B., Tripathi, P.S. and Tripathi, M.P.C. 2012. Bioactivity of two plant derived essential oils against
the rice weevils Sitophilus oryzae (L.) (Coleoptera: Curculionidae). Proceedings of the National
Academy of Sciences India Section B - Biological Sciences, 83 (2).
Nerio, S.L., Olivero-Verbel, J. and Stashenko, E.E. 2009. Repellency activity of essential oils from sevenaromatic plants grown in Colombia against Sitophilus zeamais Motschulsky (Coleoptera). Journal ofStored Products Research, 45, 212-214.
Park, I.K., Lee, S.G., Choi, D.H., Park, J.D. and Ahn, Y.J. 2003. Insecticidal activities of constituents
identified in the essential oil from leaves of Chamaecyparis obtusa against Callosobruchus chinensis (L.)
and Sitophilus oryzae (L.). Journal of Stored Products Research, 39 (4), 375-384.
Vairappan, S.C. and Nagappan, T. 2014. Major volatile hydrocarbons of rice paddy herb, Limnophila
aromatica Lam. Merr as possible chemotaxonomic marker. Journal of Tropical Biology andConservation, 11, 41-48.

Ⓒ ISERD168