The biological control of maize pest
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This is my presentation that I gave in the "Pests and diseases of tropical crops" course module. It's actually a literature review of the research article by D.J. Bergvenson and S. GarciaLara.
Transcript of The biological control of maize pest
Journal of Stored Products Research Synergistic effects of insect-resistant maize and Teretrius nigrescens on the reduction of grain losses caused by Prostephanus truncatus (Horn.) D.J. Bergvinson, S. Garcia-Lara
Journal of Stored Products Research
Synergistic effects of insect-resistant maize and Teretrius nigrescens on the reduction of grain losses caused by Prostephanus truncatus (Horn.)D.J. Bergvinson, S. Garcia-LaraRepresented bySyeda Rubab Z. RizviContentsIntroductionMaterials and MethodsResults and DiscussionConclusionReferencesIntroductionProstephanus truncatus The bad guy:Larger grain borer; storage pestArthropoda; Insecta; Coleoptera; BostrichidaeNative to MesoamericaHosts: Maize and Cassava Cause of 10 45% maize losses in Africa
IntroductionProstephanus truncatus The bad guy:Successful pest due to its35 weeks longevityhigh flight activity reproduction under versatile conditionstolerance to insecticides (Pyrethroids or inert dusts)
IntroductionProstephanus truncatus The bad guy:Control measures against the pest attack:Chemical: applying mixture of Silica and AbamectinHost plant resistance: use of resistant cultivarsMechanical fortification: strengthening of pericarp cellwallsAntibiosis: toxic compounds in endosperm layerBiological: parasitoid Teretrius nigrescens
IntroductionTeretrius nigrescens The good guy:Natural enemy of P. truncatusArthropoda; Insecta; Coleoptera; HisteridaeStrong preference for adults and larva of P. truncatusHigher fecundity rate than P. truncatus
IntroductionAim of ResearchTo investigate the potential of Integrated Pest Management (IPM) against Prostephanus truncatususing both insect resistant maize plants Teretrius nigrescensMaterials and MethodsMaize genotypes:Source: CIMMYT, MexicoTwo maize varieties selected:Resistant variety (P84c3)Susceptible variety (CML244 x CML349 hybrid)
After harvest, stored at 4oC toPrevent pest damageConserve seed qualityMaterials and MethodsInsect pest culture:Source: CIMMYT, MexicoIn a 0.5 L glass jar, added400g equilibrated maize10g maize frass250 unsexed adults of P. truncatus
After 6 8 weeks:Progeny was collectedAdults obtained by sieving > 50 % damaged grain
Materials and MethodsInsect predator culture:Source: Maize storage facilities, MexicoIn a 0.5 L glass jar, added400g equilibrated maize200 unsexed and unaged adults of P. truncatus
After 2 weeks:Added 20 unsexed and unaged adults of T. nigrescensThen removed 2 weeks later
Materials and MethodsInsect population dynamics and susceptability parameters:Exp. 1Exp. 2Exp. 3Exp. 4Susceptible maize+P. truncatus (100 unsexed adults)Resistant maize+P. truncatus (100 unsexed adults)Susceptible maize+P. truncatus (100 unsexed adults)+T. nigrescens (30 unsexed adults)Resistant maize+P. truncatus (100 unsexed adults)+T. nigrescens (30 unsexed adults)Materials and MethodsInsect population dynamics and susceptability parameters:Kept for 28 weeksMonthly separation via mesh sieves, ofMaize grain for grain weight loss calculationFrass for frass productionP. truncatus adults for counting no.T. nigrescens adults for counting no.At the end, all P. truncatus and T. nigrescens adults were counted and weighedMaterials and MethodsStatistical Analysis:ANOVA model usedAnalysis of variance using Statistix v.7Comparison of differences among means via Tukey-Kramer HSD test at P
