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Lv L, Guo X, Zhao A, Liu Y, Li H, Chen X. Combined analysis of metabolome and transcriptome of wheat kernels reveals constitutive defense mechanism against maize weevils. FRONTIERS IN PLANT SCIENCE 2023; 14:1147145. [PMID: 37229118 PMCID: PMC10204651 DOI: 10.3389/fpls.2023.1147145] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/18/2023] [Accepted: 04/12/2023] [Indexed: 05/27/2023]
Abstract
Sitophilus zeamais (maize weevil) is one of the most destructive pests that seriously affects the quantity and quality of wheat (Triticum aestivum L.). However, little is known about the constitutive defense mechanism of wheat kernels against maize weevils. In this study, we obtained a highly resistant variety RIL-116 and a highly susceptible variety after two years of screening. The morphological observations and germination rates of wheat kernels after feeding ad libitum showed that the degree of infection in RIL-116 was far less than that in RIL-72. The combined analysis of metabolome and transcriptome of RIL-116 and RIL-72 wheat kernels revealed differentially accumulated metabolites were mainly enriched in flavonoids biosynthesis-related pathway, followed by glyoxylate and dicarboxylate metabolism, and benzoxazinoid biosynthesis. Several flavonoids metabolites were significantly up-accumulated in resistant variety RIL-116. In addition, the expression of structural genes and transcription factors (TFs) related to flavonoids biosynthesis were up-regulated to varying degrees in RIL-116 than RIL-72. Taken together, these results indicated that the biosynthesis and accumulation of flavonoids contributes the most to wheat kernels defense against maize weevils. This study not only provides insights into the constitutive defense mechanism of wheat kernels against maize weevils, but may also play an important role in the breeding of resistant varieties.
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Affiliation(s)
| | | | | | | | - Hui Li
- *Correspondence: Hui Li, ; Xiyong Chen,
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Aulicky R, Stejskal V, Frydova B, Athanassiou C. Evaluation of Phosphine Resistance in Populations of Sitophilus oryzae, Oryzaephilus surinamensis and Rhyzopertha dominica in the Czech Republic. INSECTS 2022; 13:1162. [PMID: 36555073 PMCID: PMC9787142 DOI: 10.3390/insects13121162] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/21/2022] [Revised: 12/08/2022] [Accepted: 12/14/2022] [Indexed: 06/17/2023]
Abstract
Phosphine is globally the most widely adopted fumigant for the control of storage pests. Recently, an increase in the frequency of stored-product pest resistance has been observed with significant geographical and interspecific variations. In this context, there are available data for the occurrence of resistant populations from America, Asia, Africa, and Australia, but there are few data in the case of Europe. Therefore, the aim of this work was to evaluate phosphine efficacy in important beetle pests of stored products, i.e., Sitophilus oryzae (L.), Oryzaephilus surinamensis (L.), and Rhyzopertha dominica (F.) sampled from the Czech Republic, using a rapid diagnostic test that is based on the speed to knockdown after exposure. Apart from the standard laboratory populations, which were used as the controls, we tested 56 field populations of these three species, collected in Czech farm grain stores. The survey revealed that 57.1% of the tested field populations were classified as phosphine-susceptible, based on the knockdown method used. However, profound variations among species and populations were recorded. The species with the highest percentage of resistant populations was R. dominica (71.4% of the populations; resistance coefficient 0.5-4.1), followed by S. oryzae (57.1% of the populations; resistance coefficient 0.8-6.9), and O. surinamensis (9.5% of the populations; resistance coefficient 0.5-2.9). Regarding the intra-population variability in response to phosphine (slope of the knockdown time regression), the laboratory and slightly resistant populations of all species were homogenous, whereas the most resistant populations were strongly heterogeneous. Our data show that the occurrence of resistance in the Czech Republic is relatively widespread and covers a wide range of species, necessitating the need for the adoption of an action plan for resistance mitigation.
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Affiliation(s)
- Radek Aulicky
- Crop Research Institute, Drnovska 507, 161 00 Prague, Czech Republic
| | - Vaclav Stejskal
- Crop Research Institute, Drnovska 507, 161 00 Prague, Czech Republic
| | - Barbora Frydova
- Crop Research Institute, Drnovska 507, 161 00 Prague, Czech Republic
| | - Christos Athanassiou
- Laboratory of Entomology and Agricultural Zoology, Department of Agriculture, Crop Production and Rural Environment, University of Tessaly, Phytokou Str., 38446 Nea Ionia, Magnesia, Greece
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Afful E, Tadesse TM, Nayak MK, Phillips TW. High-dose strategies for managing phosphine-resistant populations of Rhyzopertha dominica (F.) (Coleoptera: Bostrichidae). PEST MANAGEMENT SCIENCE 2020; 76:1683-1690. [PMID: 31749328 DOI: 10.1002/ps.5688] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/17/2019] [Revised: 11/10/2019] [Accepted: 11/17/2019] [Indexed: 06/10/2023]
Abstract
BACKGROUND Rhyzopertha dominica is a serious pest of stored grains and many populations have resistance to the fumigant phosphine. Some populations contain beetles with a 'strong resistance' phenotype. Recent work found the LC50 values for two strong-resistant populations recently studied in North America, Belle Glade and Minneapolis were 100- and 595-fold higher, respectively, compared to LC50 of a lab-susceptible strain. Populations with 'weak-resistant' phenotypes had LC50 values 5- to 10-fold that of a susceptible strain. The work reported below aimed to determine the minimum phosphine concentrations and number of days of exposure needed to effectively control all life stages of representative weak- and strong-resistant strains, and then to recommend the treatment conditions needed to control strongly phosphine-resistant R. dominica in pest populations. RESULTS A dose-mortality assay estimated that phosphine fumigation over 48 h using 730-870 ppm at 25° C would control adults of both strongly resistant R. dominica populations. Fumigations with mixed life stage cultures found 200 ppm killed all susceptible and weak-resistant beetles in 2 days, but the strong-resistant Minneapolis and Belle Glade strains had substantial survivors at 200 ppm. Furthermore, the Belle Glade strain had beetles that survived 1000 ppm in 2-day fumigations. The strong-resistant Belle Glade strain needed nearly 10 days at over 400 ppm to have acceptable levels of control. CONCLUSION This study recommends protocols to manage strongly resistant R. dominica populations provided that a minimum phosphine concentration of 400 ppm be maintained at 25° C or higher for up to 10 days. © 2019 Society of Chemical Industry.
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Affiliation(s)
- Edwin Afful
- Department of Entomology, Kansas State University, Manhattan, KS, USA
| | - Tesfaye M Tadesse
- Department of Plant Science, Bahir Dar University, Bahir Dar, Ethiopia
| | - Manoj K Nayak
- Department of Agriculture and Fisheries, Queensland Ecosciences Precinct, Brisbane, Australia
- Plant Biosecurity Cooperative Research Centre, GPO Box 5012, Bruce, ACT 2617, Australia
| | - Thomas W Phillips
- Department of Entomology, Kansas State University, Manhattan, KS, USA
- Plant Biosecurity Cooperative Research Centre, GPO Box 5012, Bruce, ACT 2617, Australia
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H. Qari S, Abdel-Fatt NA, A. Shehawy A. Assessment of DNA Damage and Biochemical Responses in Rhyzopertha dominica Exposed to Some Plant Volatile Oils. ACTA ACUST UNITED AC 2017. [DOI: 10.3923/jpt.2017.87.96] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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Manivannan S, Swati AP, Hemalatha P, Gisha EK, Roopa RS. Phosphine gas generated from an aluminium phosphide tablet exhibits early knock down effects on tamarind pod borer. RSC Adv 2016. [DOI: 10.1039/c6ra05670a] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
The tamarind pod borer, Sitophilus linearis (Herbst), is highly susceptible to phosphine fumigation compared to its congener, Sitophilus oryzae.
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Affiliation(s)
- S. Manivannan
- Food Protectants and Infestation Control Department
- CSIR-Central Food Technological Research Institute
- Mysore
- India
| | - A. P. Swati
- Food Protectants and Infestation Control Department
- CSIR-Central Food Technological Research Institute
- Mysore
- India
| | - P. Hemalatha
- Food Protectants and Infestation Control Department
- CSIR-Central Food Technological Research Institute
- Mysore
- India
| | - E. K. Gisha
- Food Protectants and Infestation Control Department
- CSIR-Central Food Technological Research Institute
- Mysore
- India
| | - R. S. Roopa
- Food Protectants and Infestation Control Department
- CSIR-Central Food Technological Research Institute
- Mysore
- India
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Kaur R, Nayak MK. Developing effective fumigation protocols to manage strongly phosphine-resistant Cryptolestes ferrugineus (Stephens) (Coleoptera: Laemophloeidae). PEST MANAGEMENT SCIENCE 2015; 71:1297-1302. [PMID: 25329520 DOI: 10.1002/ps.3926] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/05/2014] [Revised: 10/14/2014] [Accepted: 10/14/2014] [Indexed: 06/04/2023]
Abstract
BACKGROUND The emergence of high levels of resistance in Cryptolestes ferrugineus (Stephens) in recent years threatens the sustainability of phosphine, a key fumigant used worldwide to disinfest stored grain. We aimed at developing robust fumigation protocols that could be used in a range of practical situations to control this resistant pest. RESULTS Values of the lethal time to kill 99.9% (LT99 .9 , in days) of mixed-age populations, containing all life stages, of a susceptible and a strongly resistant C. ferrugineus population were established at three phosphine concentrations (1.0, 1.5 and 2.0 mg L(-1) ) and three temperatures (25, 30 and 35 °C). Multiple linear regression analysis revealed that phosphine concentration and temperature both contributed significantly to the LT99 .9 of a population (P < 0.003, R2 = 0.92), with concentration being the dominant variable, accounting for 75.9% of the variation. Across all concentrations, LT99.9 of the strongly resistant C. ferrugineus population was longest at the lowest temperature and shortest at the highest temperature. For example, 1.0 mg L(-1) of phosphine is required for 20, 15 and 15 days, 1.5 mg L(-1) for 12, 11 and 9 days and 2.0 mg L(-1) for 10, 7 and 6 days at 25, 30 and 35 °C, respectively, to achieve 99.9% mortality of the strongly resistant C. ferrugineus population. We also observed that phosphine concentration is inversely proportional to fumigation period in regard to the population extinction of this pest. CONCLUSION The fumigation protocols developed in this study will be used in recommending changes to the currently registered rates of phosphine in Australia towards management of strongly resistant C. ferrugineus populations, and can be repeated in any country where this type of resistance appears.
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Affiliation(s)
- Ramandeep Kaur
- Agri-Science Queensland, Department of Agriculture, Fisheries and Forestry, Brisbane, QLD, Australia
- Plant Biosecurity Cooperative Research Centre, Bruce, ACT, Australia
| | - Manoj K Nayak
- Agri-Science Queensland, Department of Agriculture, Fisheries and Forestry, Brisbane, QLD, Australia
- Plant Biosecurity Cooperative Research Centre, Bruce, ACT, Australia
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Manivannan S. Toxicity of phosphine on the developmental stages of rust-red flour beetle, Tribolium castaneum Herbst over a range of concentrations and exposures. Journal of Food Science and Technology 2015; 52:6810-5. [PMID: 26396434 DOI: 10.1007/s13197-015-1799-y] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Revised: 03/03/2015] [Accepted: 03/04/2015] [Indexed: 10/23/2022]
Abstract
The susceptibility of the developmental stages of rust-red flour beetle, Tribolium castaneum to a range of concentrations of phosphine over varying durations from 24 to 168 h was reconnoitered in the laboratory at 25 ± 2 °C. Responses of the life stages exposed to phosphine were compared with those of un-treated controls over 24, 48, 72, 96, 120, 144 and 168 h exposures and mortality was assessed after 14 days. Among the life stages tested, pupae were more tolerant to phosphine followed by the egg and the larval instars. At 24 h, the maximum LC50 value was observed in case of egg; 1.571 mgL(-1); followed by the pupae, 6(th) instar, 4(th) instar and 2(nd) instar larvae with LC50 values of 1.184, 0.336, 0.212 and 0.081 mgL(-1) respectively. However, continued exposure of the developmental stages to phosphine, recorded maximum LC values in the pupae followed by egg and the larval instars. A linear increase in the mortality response was witnessed in all the insect stages when the exposure periods were extended from 24 to 168 h with increasing concentrations of phosphine, conversely significant increase in mortality was greatly apparent during the initial treatment periods.
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Affiliation(s)
- S Manivannan
- Food Protectants and Infestation Control Department, CSIR-Central Food Technological Research Institute, Mysore, 570 020 India
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Nayak MK, Holloway JC, Emery RN, Pavic H, Bartlet J, Collins PJ. Strong resistance to phosphine in the rusty grain beetle, Cryptolestes ferrugineus (Stephens) (Coleoptera: Laemophloeidae): its characterisation, a rapid assay for diagnosis and its distribution in Australia. PEST MANAGEMENT SCIENCE 2013; 69:48-53. [PMID: 22807213 DOI: 10.1002/ps.3360] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/02/2011] [Revised: 04/26/2012] [Accepted: 05/23/2012] [Indexed: 06/01/2023]
Abstract
BACKGROUND The recent development of very high resistance to phosphine in rusty grain beetle, Cryptolestes ferrugineus (Stephens), seriously threatens stored-grain biosecurity. The aim was to characterise this resistance, to develop a rapid bioassay for its diagnosis to support pest management and to document the distribution of resistance in Australia in 2007-2011. RESULTS Bioassays of purified laboratory reference strains and field-collected samples revealed three phenotypes: susceptible, weakly resistant and strongly resistant. With resistance factors of > 1000 × , resistance to phosphine expressed by the strong resistance phenotype was higher than reported for any stored-product insect species. The new time-to-knockdown assay rapidly and accurately diagnosed each resistance phenotype within 6 h. Although less frequent in western Australia, weak resistance was detected throughout all grain production regions. Strong resistance occurred predominantly in central storages in eastern Australia. CONCLUSION Resistance to phosphine in the rusty grain beetle is expressed through two identifiable phenotypes: weak and strong. Strong resistance requires urgent changes to current fumigation dosages. The development of a rapid assay for diagnosis of resistance enables the provision of same-day advice to expedite resistance management decisions.
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Affiliation(s)
- Manoj K Nayak
- Department of Employment, Economic Development and Innovation, Brisbane, Queensland, Australia.
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Mau YS, Collins PJ, Daglish GJ, Nayak MK, Ebert PR. The rph2 gene is responsible for high level resistance to phosphine in independent field strains of Rhyzopertha dominica. PLoS One 2012; 7:e34027. [PMID: 22461899 PMCID: PMC3312893 DOI: 10.1371/journal.pone.0034027] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2012] [Accepted: 02/20/2012] [Indexed: 11/19/2022] Open
Abstract
The lesser grain borer Rhyzopertha dominica (F.) is one of the most destructive insect pests of stored grain. This pest has been controlled successfully by fumigation with phosphine for the last several decades, though strong resistance to phosphine in many countries has raised concern about the long term usefulness of this control method. Previous genetic analysis of strongly resistant (SR) R. dominica from three widely geographically dispersed regions of Australia, Queensland (SRQLD), New South Wales (SRNSW) and South Australia (SRSA), revealed a resistance allele in the rph1 gene in all three strains. The present study confirms that the rph1 gene contributes to resistance in a fourth strongly resistant strain, SR2QLD, also from Queensland. The previously described rph2 gene, which interacts synergistically with rph1 gene, confers strong resistance on SRQLD and SRNSW. We now provide strong circumstantial evidence that weak alleles of rph2, together with rph1, contribute to the strong resistance phenotypes of SRSA and SR2QLD. To test the notion that rph1 and rph2 are solely responsible for the strong resistance phenotype of all resistant R. dominica, we created a strain derived by hybridising the four strongly resistant lines. Following repeated selection for survival at extreme rates of phosphine exposure, we found only slightly enhanced resistance. This suggests that a single sequence of genetic changes was responsible for the development of resistance in these insects.
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Affiliation(s)
- Yosep S. Mau
- School of Integrative Biology, The University of Queensland, Saint Lucia, Queensland, Australia
- Faculty of Agriculture, The University of Nusa Cendana, Kupang, Nusa Tenggara Timur, Indonesia
| | - Patrick J. Collins
- Department of Employment, Economic Development and Innovation, Ecosciences Precinct, Brisbane, Queensland, Australia
- Cooperative Research Centre for National Plant Biosecurity, Bruce, Australian Capital Territory, Australia
| | - Gregory J. Daglish
- Department of Employment, Economic Development and Innovation, Ecosciences Precinct, Brisbane, Queensland, Australia
- Cooperative Research Centre for National Plant Biosecurity, Bruce, Australian Capital Territory, Australia
| | - Manoj K. Nayak
- Department of Employment, Economic Development and Innovation, Ecosciences Precinct, Brisbane, Queensland, Australia
- Cooperative Research Centre for National Plant Biosecurity, Bruce, Australian Capital Territory, Australia
| | - Paul R. Ebert
- School of Integrative Biology, The University of Queensland, Saint Lucia, Queensland, Australia
- * E-mail:
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Ukeh DA, Birkett MA, Bruce TJA, Allan EJ, Pickett JA, Luntz AJM. Behavioural responses of the maize weevil, Sitophilus zeamais, to host (stored-grain) and non-host plant volatiles. PEST MANAGEMENT SCIENCE 2010; 66:44-50. [PMID: 19760598 DOI: 10.1002/ps.1828] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
BACKGROUND Four-arm olfactometer bioassays were conducted to assess the behavioural responses of the adult maize weevil, Sitophilus zeamais (Motschulsky) (Coleoptera: Curculionidae), to harvested seeds of host plants, i.e. white maize, yellow maize (Zea mays L.) and winter wheat (Triticum aestivum L.) (Poaceae), and non-host plant materials, i.e. alligator pepper, Aframomum melegueta (Rosk) K. Schum (Zingiberaceae), rhizomes of ginger, Zingiber officinale (Roscoe) (Zingiberaceae), and West African black pepper, Piper guineense Thonn and Schum (Piperaceae). Additional bioassays with host plant volatiles were conducted in the presence of three doses of non-host plant materials. RESULTS Both sexes of the weevil showed strong attraction to maize and wheat seed volatiles, but were significantly repelled (P < 0.001) by odours from A. melegueta, Z. officinale and P. guineense. Furthermore, S. zeamais avoided maize and wheat seeds presented in combination with the non-host plant material at 10% (w/w) and 33% (w/w) levels. CONCLUSIONS A. melegueta, Z. officinale and P. guineense have the potential for use in the protection of stored grains by resource-poor farmers with local access to these plants.
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Affiliation(s)
- Donald A Ukeh
- School of Biological Sciences, University of Aberdeen, Aberdeen, UK
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Nayak MK, Collins PJ. Influence of concentration, temperature and humidity on the toxicity of phosphine to the strongly phosphine-resistant psocid Liposcelis bostrychophila Badonnel (Psocoptera: Liposcelididae). PEST MANAGEMENT SCIENCE 2008; 64:971-976. [PMID: 18416433 DOI: 10.1002/ps.1586] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
BACKGROUND The psocid Liposcelis bostrychophila Badonnel, is a widespread, significant pest of stored commodities, has developed strong resistance to phosphine, the major grain disinfestant. The aim was to develop effective fumigation protocols to control this resistant pest. RESULTS Time to population extinction of all life stages (TPE) in days was evaluated at a series of phosphine concentrations and temperatures at two relative humidities. Regression analysis showed that temperature, concentration and relative humidity all contributed significantly to describing TPE (P<0.001, R(2)=0.95), with temperature being the dominant variable, accounting for 74.4% of the variation. Irrespective of phosphine concentration, TPE was longer at lower temperatures and high humidity (70% RH) and shorter at higher temperatures and low humidity (55% RH). At any concentration of phosphine, a combination of higher temperature and lower humidity provides the shortest fumigation period to control resistant L. bostrychophila. For example, 19 and 11 days of fumigation are required at 15 degrees C and 70% RH at 0.1 and 1.0 mg L(-1) of phosphine respectively, whereas only 4 and 2 days are required at 35 degrees C and 55% RH for the same respective concentrations. CONCLUSIONS The developed fumigation protocols will provide industry with flexibility in application of phosphine.
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Affiliation(s)
- Manoj K Nayak
- Department of Primary Industries and Fisheries, 80 Meiers Road, Indooroopilly, Queensland 4068, Australia.
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Cinco-Moroyoqui FJ, Díaz-Malváez FI, Alanís-Villa A, Barrón-Hoyos JM, Cárdenas-López JL, Cortez-Rocha MO, Wong-Corral FJ. Isolation and partial characterization of three isoamylases of Rhyzopertha dominica F. (Coleoptera: Bostrichidae). Comp Biochem Physiol B Biochem Mol Biol 2008; 150:153-60. [DOI: 10.1016/j.cbpb.2008.02.008] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2007] [Revised: 02/20/2008] [Accepted: 02/21/2008] [Indexed: 10/22/2022]
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Jayasekara TK, Stevenson PC, Hall DR, Belmain SR. Effect of Volatile Constituents from Securidaca Longepedunculata on Insect pests Of Stored Grain. J Chem Ecol 2005; 31:303-13. [PMID: 15856785 DOI: 10.1007/s10886-005-1342-0] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
Securidaca longepedunculata Fers (Polygalaceae) is commonly used as a traditional medicine in many parts of Africa as well as against a number of invertebrate pests, including insects infesting stored grain. The present study showed that S. longepedunculata root powder, its methanol extract, and the main volatile component, methyl salicylate, exhibit repellent and toxic properties to Sitophilus zeamais adults. Adult S. zeamais that were given a choice between untreated maize and maize treated with root powder, extract, or synthetic methyl salicylate in a four-way choice olfactometer significantly preferred the control maize. Methyl salicylate vapor also had a dose-dependant fumigant effect against S. zeamais, Rhyzopertha dominica, and Prostephanus truncates, with a LD100 achieved with a 60microl dose in a 1-l container against all three insect species after 24 hr of exposure. Probit analyses estimated LD50 values between 34 and 36 microl (95% CI) for all insect species. Furthermore, prolonged exposure for 6 days showed that lower amounts (30 microl) of methyl salicylate vapor were able to induce 100% adult mortality of the three insect species. The implications are discussed in the context of improving stored product pest control by small-scale subsistence farmers in Africa.
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Affiliation(s)
- Thamara K Jayasekara
- Natural Resources Institute, University of Greenwich, Central Avenue Chatham Maritime, Kent ME4 4TB, United Kingdom
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