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Insecticidal Evaluation of Some Plant Materials as Grain Protectants Against the Maize Weevil, Sitophilus zeamais (Mots) (Coleoptera: Curclionidae)
S.T. Arannilewa,O.O. Odeyemi
Agricultural Journal , 2013,
Abstract: Laboratory experiments were carried out to investigate the efficacy of ethanolic extract of four plant materials, namely: Zanthoxylum xanthoxyloides (Lam.) Waterm., Aristolochia ringens(Vahl), Colocasia esculenta (L.) Schott and Morinda lucida (L) on the maize weevil Sitophilus zeamais (Mots). Parameters assessed were adults toxicity, adult emergence, percentage of reduction of plants and damage effect of weevils to the grains at 0.0, 1.0, 1.5 and 2.0% (w/v) concentrations. Zanthoxylum xanthoxyloides evoked 100% adult mortality within 24 h after treatment; and A. ringens also significantly caused 100% mortality within 48 h. Aristolochia ringens at all concentrations provided good protection to the grains stored for 49 days and also gave 100% reduction value as well as 0.00% damage and 0.00 Weevil Perforation Index. This study therefore revealed the grain protectant ability of A .ringens and Z. xanthoxyloides on the maize weevil, Sithophlius zeamais. The bioassay procedure used and results obtained are reported.
A Simple Laboratory Prescreen for Plants with Grain Protectant Effects Against the Maize Weevil; Sitophilus zeamais (Mots) (Coleoptera: Curculionidae)
S.T. Arannilewa
Agricultural Journal , 2013,
Abstract: A simple bioassay technique to assess pulverized indigenous plant materials for ability to protect maize grains from damage by weevils during storage, was employed. Of the 9 plants that were screened, Zanthoxylum xanthoxyloides (Lam.) Waterm. (Rutaceae), Aristolochia ringens Vahl. (Aristolochiaceae) and Morinda lucida Linn. (Rubiaceae) showed best protectant effects on adult toxicity, adult emergence and Weevil Perforation Index (WPI). The details of the bioassay procedure used and the results obtained are reported.
Selection of Beauveria bassiana (Bals.) Vuill. isolates for controlling Sitophilus zeamais (Mots.) (Coleoptera: Curculionidae)
Rondelli,Vando Miossi; de Carvalho,José Romário; Pratissoli,Dirceu; Polanczyk,Ricardo Antonio; de Alencar,Jo?o Rafael De Conte Carvalho; Zinger,Fernando Domingo; Pereira,Sara Maria Andrade;
Idesia (Arica) , 2012, DOI: 10.4067/S0718-34292012000300013
Abstract: sitophilus zeamais (mots.) (coleoptera: curculionidae) is considered a major pest of maize, responsible for reducing grain quality and making the corn inappropriate for industrial use and human consumption. s. zeamais has been controlled exclusively with chemical products. the objective of this research was to select isolates of beauveria bassiana (bals.) vuill. to control s. zeamais. beetles were immersed in conidia suspensions of each isolate for five seconds and placed in a gerbox container with maize grains. in pathogenicity tests, the isolates that caused the highest mortality to the maize weevil were esalq-447 (68.0%), cca-ufes/ bb-36 (57.3%) and cca-ufes/bb-31 (51.3%). esalq-447 was the most virulent, with an lc50 of 1.7 x 107 conidia/ml and shows promise for controlling maize weevils. these isolates of b. bassiana can be used as effective substitutes for conventional chemical control, normally carried out with phosphine. further tests should be performed under field and semi-field conditions to develop an appropriate strategy for the use of this entomopathogen to manage s. zeamais.
Bioatividade da erva-de-santa-maria, Chenopodium ambrosioides L., sobre Sitophilus zeamais Mots. (Coleoptera: Curculionidae)
Tavares, Márcio A.G.C.;Vendramim, José D.;
Neotropical Entomology , 2005, DOI: 10.1590/S1519-566X2005000200021
Abstract: this work deals with the influence of the powder and aqueous extracts of chenopodium ambrosioides l. on behaviour and survival of the maize weevil, sitophilus zeamais mots. the powders tested were obtained from leaves, branches, fruits and the whole plant (with fruits), when the plant was in the fructification period. the insects were obtained from a population reared on wheat grains. the effect of the powders from the different vegetal structures and from the whole plant (with fruits) was evaluated concerning the insect behavior (attractiveness and/or repellence) and insecticide activity on the adult phase. the insecticide activity of the aqueous extract from the different structures and from the whole plant (with fruits) was evaluated on immature and adult s. zeamais. the results were as follows: a) powders from fruits, branches and leaves of c. ambrosioides were not repellent to s. zeamais adults; b) powders from fruits and whole plant (with fruits) presented insecticide activity against s. zeamais adults; c) the aqueous extracts from these structures did not affect survival and adult emergence in s. zeamais.
Selection of Beauveria bassiana (Bals.) Vuill. isolates for controlling Sitophilus zeamais (Mots.) (Coleoptera: Curculionidae) Sele o de isolados de Beauveria bassiana (Bals.) Vuill. para o controle de Sitophilus zeamais (Mots.) (Coleoptera: Curculionidae)
Vando Miossi Rondelli,José Romário de Carvalho,Dirceu Pratissoli,Ricardo Antonio Polanczyk
IDESIA , 2012,
Abstract: Sitophilus zeamais (Mots.) (Coleoptera: Curculionidae) is considered a major pest of maize, responsible for reducing grain quality and making the corn inappropriate for industrial use and human consumption. S. zeamais has been controlled exclusively with chemical products. The objective of this research was to select isolates of Beauveria bassiana (Bals.) Vuill. to control S. zeamais. Beetles were immersed in conidia suspensions of each isolate for five seconds and placed in a gerbox container with maize grains. In pathogenicity tests, the isolates that caused the highest mortality to the maize weevil were ESALQ-447 (68.0%), CCA-UFES/ Bb-36 (57.3%) and CCA-UFES/Bb-31 (51.3%). ESALQ-447 was the most virulent, with an LC50 of 1.7 x 10(7) conidia/ml and shows promise for controlling maize weevils. These isolates of B. bassiana can be used as effective substitutes for conventional chemical control, normally carried out with phosphine. Further tests should be performed under field and semi-field conditions to develop an appropriate strategy for the use of this entomopathogen to manage S. zeamais. Sitophilus zeamais (Mots.) (Coleoptera: Curculionidae) é considerado uma das principais pragas do milho, responsável pela redu o da qualidade dos gr os, tornando-os impróprios para indústria e consumo humano. Para seu controle tem-se utilizado exclusivamente produtos químicos. Assim, o objetivo deste trabalho foi selecionar isolados de Beauveria bassiana (Bals.) Vuill. para o controle de S. zeamais. Besouros foram imersos em suspens es de conídios de cada isolado por cinco segundos e acondicionados em gerbox contendo gr os de milho. Nos testes de patogenicidade os isolados que causaram maior mortalidade confirmada ao gorgulho-do-milho foram ESALQ-447 (68,0%), CCA-UFES/Bb-36 (57,3%) e CCA-UFES/Bb-31 (51,3%), sendo o primeiro mais virulento e promissor ao controle desta praga com CL50 de 1,7 x 10(7) conídios/ml. A utiliza o desses isolados de B. bassiana pode ser um substituto eficaz ao controle convencional realizado, normalmente, com fosfina. Testes devem ser feitos em campo e semi-campo para elabora o de uma estratégia adequada para utiliza o deste entomopatógeno no manejo de S. zeamais.
Tagetes Minuta Formulation Effect Sitophilus Zeamais (Weevils) Control in Stored Maize Grain
International Journal of Plant Research , 2012, DOI: 10.5923/j.plant.20120203.04
Abstract: The research was carried out at Chaminuka Training Centre in Mt Darwin district of Zimbabwe. Maize producers in the rural areas are challenged by storage pests particularly the Sitophilus zeamais. Affordable and readily available protectants are needed. A common weed, Tagetes minuta, was assessed for its potential to control Sitophilus zeamais. This provides a sustainable and degradable pesticide to the poor farmers. Maize grain samples arranged in a complete randomized design (CRD) were infected with 32 weevils each. The research was run for 8 weeks with the objectives to determine the efficacy of varying forms of Tagetes minuta on Sitophilus zeamais and to establish the effect of Tagetes minuta on maize grain weight loss. Weevil counts were taken on fortnight bases to establish mortalities. Grain weight loss was assessed using the Thousand Grain Method (T G M). There were variations on treatments with varied forms. The ground Tagetes minuta had the highest effect on both weight loss and weevil mortality compared to un- ground Tagetes minuta (p = 0.001). It was concluded that the ground Tagetes minuta works through a wider spectrum by causing physical and physiological effects on the weevil resulting in mortalities.
Sources of Resistance to the Maize Weevil Sitophilus zeamais in Tropical Maize  [cached]
Mwololo J. K.,Mugo S.,Okori P.,Tefera T.
Journal of Agricultural Science , 2012, DOI: 10.5539/jas.v4n11p206
Abstract: The maize weevil, Sitophilus zeamais (Motschulsky) (Coleoptera: Curculionidae), is among the major storage pests that enhance food insecurity among maize farmers. New sources of resistance to the maize weevil are critical in a successful breeding program to address grain damage by postharvest pests. The objective of the study was to evaluate resistance in maize genotypes to the maize weevil, and consequently their value for use in breeding programs. A total of 175 genotypes, including hybrids, landraces, open-pollinated varieties and checks, were tested for resistance to the maize weevil. The percentage grain damage, weight loss, flour weight and weight of damaged and undamaged grains were measured. Significant differences (P <0.001) were observed among the genotypes for all the traits evaluated. The distribution of the genotypes among the different categories of resistance was an indication of the existence of genetic variation. The most resistant genotypes were CKPH08003 and BRAZ 2451 while the most susceptible were PH 3254 and BRAZ 4, among the hybrids and landraces respectively. Genotypes that were superior to the resistant checks were identified. The percentage weight loss and flour weight were identified as the most important insect-resistance traits for discriminating genotypes as evident from the canonical discriminant analysis. Correlation coefficients among the traits evaluated were highly significant. The resistant hybrids identified can be recommended for release and adoption by farmers, whereas the resistant landraces can act as sources of resistance for use in breeding programs.
Controle de Sitophilus zeamais Mots., 1855 (Coleoptera: Curculionidae) com inseticidas empregados em frutíferas temperadas
Afonso, Ana Paula Schneid;Faria, Jo?o Luiz;Botton, Marcos;Loeck, Alci Enimar;
Ciência Rural , 2005, DOI: 10.1590/S0103-84782005000200001
Abstract: the maize weevil sitophilus zeamais mots. has frequently occurred in temperate fruits in the field, damaging peaches in pelotas, rs, apples in fraiburgo, sc and grapes in serra gaúcha, rs, brazil. this work evaluated in laboratory, the effect of deltamethrine (decis 25 ce, 40ml 100l-1), dimetoate (dimetoato ce 150ml 100l-1), thrichlorphon (dipterex 500 snaqc 300ml 100l-1), phosmet (imidan 500 pm, 200g 100l-1), fenthion (lebaycid 500 ce 100ml 100l-1), chlorpiriphos (lorsban 480 br, 150ml 100l-1), malathion (malation 1000, 200ml 100l-1), carbaryl (sevin 480 sc, 360ml 100l-1), fenitrothion (sumithion 500 ce, 150ml 100l-1) and methidathion (supracid 400 ce, 100ml 100l-1) commonly used in temperate fruit pest control and the new insecticides thiamethoxam (actara 250 wg, 15 e 30g 100l-1), emamectin benzoate (proclaim 5 sg, 10 e 20g 100l-1), imidacloprid (provado 200 sc, 30 e 60ml 100l-1), spinosad (tracer 480 ce, 10 e 20ml 100l-1) and etofenprox (trebon 100 sc, 100 e 150ml 100l-1). experiments were conducted treating apple fruits with an insecticide solution per 10 seconds (residual contact) and offered to adults of s. zeamais sp, and by spraying compounds directly on adults (direct contact). the insecticides trichlorfon (150g 100l-1), fenthion (50g 100l-1), chlorpiriphos (72g 100l-1), malathion (200g 100l-1), methidathion (40g 100l-1) and thiamethoxam (3.75 and 7.5g 100l-1) were efficient in the control of the maize weevil by residual contact. fenthion (50g 100l-1), chlorpiriphos (72g 100l-1), malathion (200g 100l-1), fenitrothion (75g 100l-1) and methidathion (40g 100l-1) were efficient by direct contact.
Resistance of maize varieties to the maize weevil Sitophilus zeamais (Motsch.) (Coleoptera: Curculionidae)
F Abebe, T Tefera, S Mugo, Y Beyene, S Vidal
African Journal of Biotechnology , 2009,
Abstract: This study aimed at evaluating commonly used maize varieties, collected from Melkasa and Bako Agricultural Research Centers and Haramaya University, Ethiopia, against the maize weevil Sitophilus zeamais Motsch., one of the most important cosmopolitan stored product pests in maize. A total of 13 improved maize varieties were screened for their relative susceptibility to S. zeamais. The Dobie index of susceptibility was used to group the varieties. The variety, ‘BHQP-542’, had the least index of susceptibility and was regarded as resistant. The varieties, ‘Katumani’, ‘Melkasa-I’, ‘Melkasa-II’, ‘Melkasa-III’, ‘Coree’, ‘BH-541’, ‘BH-660’, ‘BH-540’, ‘Rare-I’, ‘Awasa-511’, ‘ACV3’ and ‘ACV6’, were moderately resistant. Weevils fed with the resistant variety produced low numbers of F1 progeny, had a high median developmental time and a low percentage of seed damage and seed weight loss. Maize varieties with a high F1 progeny tended to have a short median developmental time. An increasing number of F1 progeny resulted in an increasing seed damage and seed weight loss. We found an inverse relationship between the susceptibility index and percent mortality and median developmental time; however, the numbers of F1 progeny, percent seed damage and seed weight loss were positively related with the susceptibility index. The use of resistant varieties should be promoted in managing S.zeamais in stored maize under subsistence farming conditions in Africa.
Pirimiphos-methyl residues in corn and popcorn grains and some of their processed products and the insecticide action on the control of Sitophilus zeamais Mots. (Coleoptera: Curculionidae)
Sgarbiero, Eduardo;Trevizan, Luiz R.P.;Baptista, Gilberto C. de;
Neotropical Entomology , 2003, DOI: 10.1590/S1519-566X2003000400024
Abstract: the degradation/persistence of residues of the organophosphorus insecticide pirimiphos-methyl was determined in corn and popcorn grains and in some of their processed products such as grain, bran, hominy and corn flour from corn and prepared popcorn and grain from popcorn. the action of the insecticide on the control of the corn weevil, sitophilus zeamais mots., was also evaluated. the grains were treated with the concentration of 12 mg.kg-1 (ppm) a.i. pirimiphos-methyl for the control of the weevils. samples were taken at zero, 15, 30, 60, 120 and 240 days after treatment. quantitative measurements were made by gas chromatography, by using a flame photometric detector. for pirimiphos-methyl residual action studies, samples of both types of grain were taken at 15, 30 days after treatment and subsequently at monthly intervals up to one year. treated and non-treated (control) grains were infested with weevil adults. mortality was checked 15 days after exposure. pirimiphos-methyl residues were not persistent in either types of grains or their processed products. residues dropped 5- 8-fold in corn bran and popcorn. they were stable in hominy and corn flour, but the concentration levels were low. higher residues in corn bran than in grain are related to the higher oil content in that processed product. the insecticide remained effective against the pest over the entire period of observation (1 year) for both types of grains.
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