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Paul-andré Calatayud – 1st expert on this subject based on the ideXlab platform
draft genome of Busseola fusca the maize stalk borer a major crop pest in sub saharan africaGenome Biology and Evolution, 2019Co-Authors: Kayla M Hardwick, Paul-andré Calatayud, Awino Maureiq Edith Ojwang, Francesca Stomeo, Solomon Maina, Gladys BichangaAbstract:
The maize stalk borer, Busseola fusca, is an important Lepidopteran pest of cereal crops in Central, East, and Southern Africa. Crop losses due to B. fusca feeding activity vary by region, but can result in total crop loss in areas with high levels of infestation. Genomic resources provide critical insight into the biology of pest species and can allow for the development of effective management tools and strategies to mitigate their impact on agriculture. To this end, we sequenced, assembled, and annotated the genome of B. fusca. The total assembled genome size was 492.9 Mb with 19,417 annotated protein-coding genes. Using a comparative approach, we identified a putative expansion in the Chorion gene family, which is involved in the formation of the egg shell structure. Our analysis revealed high repeat content within the B. fusca genome, with LTR sequences comprising the majority of the repetitive sequence. We hope genomic resources will provide a foundation for future work aimed at developing an integrated pest management strategy to reduce B. fusca‘s impact on food security.
Assortments of Digestive Enzymes Induced in First Instar Larvae of Busseola fusca Feeding on Different PlantsInternational Journal of Insect Science, 2019Co-Authors: G. Juma, Paul-andré CalatayudAbstract:
The stem borer Busseola fusca (Fuller) (Lepidoptera: Noctuidae) is an important pest of maize and sorghum in sub-Saharan Africa. This insect has oligophagous feeding habits, feeding mostly on maize…
influence of plant silicon in Busseola fusca lepidoptera noctuidae larvae poaceae interactionsBulletin of Entomological Research, 2015Co-Authors: G. Juma, G. Magoma, Jean Fran??ois Silvain, Peter Ahuya, G Ongamo, Le B Ru, Paul-andré CalatayudAbstract:
The noctuid stem borer Busseola fusca is an important pest of maize and sorghum in Sub-Saharan Africa. The presence of this species occurred mostly on cultivated than on wild habitats. Busseola fusca is oligophagous having a narrow range of a wild grass species. This might be due, in part, to differences in silicon (Si) content in plant tissues between cultivated and wild grasses. In the present study, we have tested this hypothesis by studying the survival and the relative growth rate (RGR) expressed as daily weight gains of B. fusca larvae on maize and six wild host plants, mostly present in the natural habitat where B. fusca occurred, and correlated with their Si contents. Survival and RGR of B. fusca larvae were considerably higher on maize and wild sorghum than on the other grass species, and they were negatively related to plant Si content. This was corroborated with results on RGR from artificial diets amended with increasing levels of Si. In addition, if Si was added to maize growing substrate B. fusca larval growth was significantly reduced confirming the involvement of Si in B. fusca larvae – Poaceae interactions. The results provide insight into the possible mechanisms of oligophagy of B. fusca and provide a correlative support for a physical role of plant endogenous Si in impeding feeding of B. fusca larvae.
J Van Den Berg – 2nd expert on this subject based on the ideXlab platform
resistance status of Busseola fusca lepidoptera noctuidae populations to single and stacked gene bt maize in south africaJournal of Economic Entomology, 2019Co-Authors: E Strydom, Annemie Erasmus, H Du Plessis, J Van Den BergAbstract:
Transgenic Bt maize expressing Cry insecticidal δ-endotoxins of Bacillus thuringiensis has been cultivated in South Africa for the control of Busseola fusca since 1998. Busseola fusca is resistant to Cry1Ab Bt maize at many localities throughout the maize production region. Pre-release evaluation (1994-1996) of the inherent susceptibility and post-release assessments (1998-2011) of resistance status of B. fusca focused on a limited number of pest populations. This study reports the current levels of susceptibility of 10 B. fusca populations evaluated between 2013 and 2017 and compared this data with previously reported data on the survival of this pest on Bt maize, including data of pre-release evaluations done during 1994 and 1995. Larval feeding bioassays in which plant tissue of maize events expressing either Cry1Ab or Cry1A.105+Cry2Ab2 (stacked event) proteins were conducted and survival and different life history parameters recorded. Results show a shift in levels of susceptibility of B. fusca to Bt maize. Pre-release evaluation of the single-gene event showed very low larval survival on Bt maize leaf tissue while studies 10 yr later and the current study reported survival of up to 40% and 100% on Cry1Ab maize, respectively. While no larvae completed their life cycle on the stacked event, higher LT50 values in this study indicate a shift in susceptibility of B. fusca to the stacked-gene event and highlight the importance of baseline information and monitoring of pest populations for their susceptibility to Bt maize.
Genetic hitchhiking and resistance evolution to transgenic Bt toxins: insights from the African stalk borer Busseola fusca (Noctuidae)Heredity, 2017Co-Authors: P Campagne, C Capdevielle-dulac, R Pasquet, S J Cornell, M Kruger, J-f Silvain, B Lerü, J Van Den BergAbstract:
Since transgenic crops expressing Bacillus thuringiensis ( Bt ) toxins were first released, resistance evolution leading to failure in control of pests populations has been observed in a number of species. Field resistance of the moth Busseola fusca was acknowledged 8 years after Bt maize was introduced in South Africa. Since then, field resistance of this corn borer has been observed at several locations, raising questions about the nature, distribution and dynamics of the resistance trait. Using genetic markers, our study identified four outlier loci clearly associated with resistance. In addition, genetic structure at neutral loci reflected extensive gene flow among populations. A realistically parameterised model suggests that resistance could travel in space at speed of several kilometres a year. Markers at outlier loci delineated a geographic region associated with resistance spread. This was an area of approximately 100 km radius, including the location where resistance was first reported. Controlled crosses corroborated these findings and showed significant differences of progeny survival on Bt plants depending on the origin of the resistant parent. Last, our study suggests diverse resistance mutations, which would explain the widespread occurrence of resistant larvae in Bt fields across the main area of maize production in South Africa.
the effect of temperature on the development and reproduction of Busseola fusca lepidoptera noctuidaeBulletin of Entomological Research, 2017Co-Authors: J Glatz, H Du Plessis, J Van Den BergAbstract:
The effect of temperature on the reproduction and development of Busseola fusca was studied under laboratory conditions. Single male-female pairs were confined to oviposition chambers kept at 15, 20, 26 and 30 ± 1°C and a 14L:10D photoperiod. Data on reproduction parameters were captured daily. Oviposition occurred at all the mentioned temperatures but no fertility was recorded at 30°C. The total number of eggs laid per female moth was between 300 and 400 and the optimum temperature for oviposition and fertility was between 20 and 26°C. Larval development was studied at five different temperature regimes, i.e. 15, 18, 20, 26 and 30 ± 1°C and a 14L:10D photoperiod. The most favourable temperature as well as the upper threshold temperature for larval development was between 26 and 30°C. Total development period was 152.6-52.6 days, respectively, at 15°C, and 26-30°C. The thermal constants for B. fusca was 99.50, 536.48, 246.25 and 893.66°D and lower temperature thresholds were 10.36, 8.14, 8.99 and 8.84°C, for completion of the egg, larval, pupal and egg-to-adult stages, respectively. Results on the thermal constants and lower and upper threshold temperatures of B. fusca can be used to predict the impact of climate change on the distribution and population growth of this pest.
J B J Van Rensburg – 3rd expert on this subject based on the ideXlab platform
Recurrent selection for resistance in maize to the African stalk borer, Busseola fusca (Fuller)The South African Journal of Plant and Soil, 2020Co-Authors: J B J Van Rensburg, J. KlopperAbstract:
Stem borer resistant inbred lines Mp704 and Mp706 of Mississippi origin were used as donor parents in a recurrent selection programme, to develop locally adapted germplasm with improved resistance to the stalk borer Busseola fusca. The segregating progenies of crosses between resistant and susceptible lines were planted ear-to-row, with selection based on the incidence of leaf feeding damage and stunting, following artificial infestation of plants with neonate larvae. Resistance derived from the two sources was combined after two cycles of selection, which resulted in high levels of resistance being achieved over a relatively short period. Combining ability for yield was evaluated at the S3 level of inbreeding, using 1137TN as tester. Compared with commercial hybrids, a number of test crosses were identified with superior yield under conditions of stalk borer infestation and comparative yields in the absence of attack. Characterization data were obtained on 42 lines intended for release.
no fitness costs associated with resistance of Busseola fusca lepidoptera noctuidae to genetically modified bt maizeCrop Protection, 2014Co-Authors: Marlene Kruger, J B J Van Rensburg, J Van Den BergAbstract:
Abstract A concern regarding planting of Bt crops is that their widespread cultivation could lead to evolution of insect resistance to Bt toxins. In South Africa, the noctuid maize stem borer ( Busseola fusca [Fuller]), is resistant to Bt maize ( Zea mays L.; MON810) which produces Cry1Ab protein. The presence of fitness costs in resistant populations could be a valuable component of resistance management since the non-Bt maize refuge may select against resistance. The aim of the study was to determine if there are fitness costs associated with Bt resistance of B . fusca . Life history parameters were compared between individuals of a Bt maize resistant B. fusca population when feeding on Bt or non-Bt maize. Similar comparisons were done using a control population. Field collected larvae as well as their F 1 -generation were used in the study. The following parameters were compared: pupal mass, moth longevity, fecundity, fertility, larval mass and survival, and sex ratio. Except for LT50-values, no fitness costs were associated with the resistance trait in the highly resistant B. fusca population. The absence of fitness costs and presence of resistant populations may promote the use of a multi-gene strategy which would be expected to impact negatively on fitness.
the influence of rainfall on the seasonal abundance and flight activity of the maize stalk borer Busseola fusca in south africaThe South African Journal of Plant and Soil, 2013Co-Authors: J B J Van Rensburg, G D J Van Rensburg, J H Giliomee, M C WaltersAbstract:
This study attempts to demonstrate the extent to which seasonal fluctuations in the number of Busseola fusca (Fuller) moths can be explained by precipitation data. Daily flight activity is shown to be enhanced by cool, humid conditions and restricted by rain. Humidity was shown experimentally to be of importance in the survival of moths under laboratory conditions. It is suspected that the observed relationship between seasonal moth numbers and rainfall is an indirect one and that survival of moths is rather determined by the direct influence of humidity. More serious infestations can therefore be expected during years with favourable rains.