Show simple item record

Developing and testing plant health management options against the maize cob borer Mussidia nigrivenella Ragonot (Lepidoptera: Pyralidae) in West Africa

dc.contributor.advisorVidal, Stefan Prof.
dc.contributor.authorAgboka, Komide
dc.titleDeveloping and testing plant health management options against the maize cob borer Mussidia nigrivenella Ragonot (Lepidoptera: Pyralidae) in West Africade
dc.title.translatedDeveloping and testing plant health management options against the maize cob borer Mussidia nigrivenella Ragonot (Lepidoptera: Pyralidae) in West Africade
dc.contributor.refereeVidal, Stefan Prof.
dc.subject.dnb630 Landwirtschaft, Veterinärmedizinde
dc.description.abstractengThe present research project aimed at developing and testing different IPM components focusing on i) habitat management particularly maize-legume intercropping and trap crops, ii) botanical formulations with special emphasis on neem and Jatropha curcas and iii) biological control using redistribution or new association approach for sustainably controlling the maize cob borer Mussidia nigrivenella Ragonot (Lepidoptera: Pyralidae) in field and in storage systems. To this end, field and lab experiments were conducted mainly in different locations in Benin. Field experiments conducted in four different locations in Benin using four by two pattern of maize-legumes or cassava planting indicated that intercrops could reduce the number of eggs and larvae of M. nigrivenella compared to the monocrop. Maize- Canavalia ensiformis and maize-Tephrosia vogelii proved to be the most effective combinations for reducing M. nigrivenella populations in the different locations. The effect of two leguminous cover crops, C. ensiformis and Sesbania rostrata and cowpea planted as border rows on infestations of maize by the pyralid M. nigrivenella and of other cob-boring lepidopteran pests was studied in two field trials. Towards harvest of both the main and minor season trials, M. nigrivenella densities were higher in the maize alone than the legume treatments, though the effect depended on the timing of planting of the cover crop in relation to that of maize. However, pest loads expressed as cumulative number of feeding-days varied with treatment during the minor season only, and they were lower on maize with C. ensiformis planted 4 weeks before maize and maize surrounded by S. rostrata than in the maize alone treatment. There were no discernable trends for other borers such as the noctuid Sesamia calamistis Hampson (Lepidoptera: Noctuidae), the pyralid Eldana saccharina Walker (Lepidoptera: P! yralidae), and the tortricid Thaumatotibia leuctotreta Meyrick (Lepidoptera: Tortricidae). Furthermore,M. nigrivenella pest loads were considerably higher on C. ensiformis than maize. Thus, the presence of alternative host plant species in the vicinity of maize fields does not increase M. nigrivenella attack on maize. The results of laboratory and field experiments using two concentrations of aqueous extracts of Tephrosia vogelii and Hyptis suaveolens, and of oils of Azadirachta indica and Jatropha curcas, as well as the pesticide Furadan 5G showed that oil emulsions of A. indica and J. curcas oils act not only as oviposition deterrent but also as ovicides. Overall, treated plants had a strong deterrent effect on ovipositing M. nigrivenella. In addition, egg hatch was adversely affected by neem and Jatropha oils. By contrast, larval survival was not affected by the treatment. In the field, Furadan, neem and J. curcas oils significantly reduced the number of M. nigrivenella larvae by 16-49.2%, while aqueous extracts of T. vogelii and H. suaveolens were similar to the control consisting of emulsified water. Although M. nigrivenella is mostly described as a field pest, it can be found feeding on stored maize up to the 4th month. Survey conducted in Benin in 2006 to assess M. nigrivenella infestations in different maize storage systems in the Southern (SGS) and Northern Guinea Savanna (SGS) showed that in SGS and NGS the percentage of infested stores decreased from 86.7% to 26.7% and from 51.4% to 14.3%, respectively, during the first 28 weeks of storage. During the same time, mean numbers of M. nigrivenella per cob decreased from 0.36 to 0.04 across both zones. All larval stages, but mostly 3rd to 5th instars, were frequently found even after more than 12 weeks, showing that M. nigrivenella could reproduce in storage. Highest M. nigrivenella incidence of 16.8% and 14.4% were found in the “Ava” and crib stores, respectively. Infestations were highest in “Ava” and lowest in maize grain stored in polyethylene bags or in mud silos. In a laborat! ory experiment, presence of post-harvest beetles negatively affected the bionomics of the cob borer indicating strong interspecific competition. Surveys for natural conducted in Malaysia pointed out the presence of three genera parasitizing Parkia speciosa pod borer: Bracon spp. (Hymenoptera: Braconidae) accounted for 64%, Eurytoma sp. (Hymenoptera: Eurytomidae) (32%) and Sphaeripalpus sp. (Hymenoptera: Pteromalidae) (4%). Overall, mortality caused by parasitoids could reach <40% hence they were considered a key mortality factor in the population dynamics of the Mussidia spp./or pyralid species in
dc.contributor.coRefereeTscharntke, Teja Prof.
dc.contributor.thirdRefereeSchütz, Stefan Prof.
dc.subject.topicAgricultural Sciencesde
dc.subject.engCanavalia ensiformisde
dc.subject.engTephrosia vogeliide
dc.subject.engMussidia nigrivenellade
dc.subject.engcover cropsde
dc.subject.engJatropha curcasde
dc.subject.engstorage systemde
dc.subject.engParkia speciosade

Files in this item


This item appears in the following Collection(s)

Show simple item record