Host plant diversity of Sesamia calamistis: cytochrome b gene sequences reveal local genetic differentiation

• Published in: Entomologia experimentalis et applicata Vol. 128; no. 1; pp. 154 - 161
• Main Authors: Ong'amo, G.O, Le Rü, B.P, Moyal, P, Calatayud, P.-A, Le Gall, P, Ogol, C.K.P.O, Kokwaro, E.D, Capdevielle-Dulac, C, Silvain, J.-F
• Format: Journal Article Conference Proceeding
• Language: English
• Published: Oxford, UK Oxford, UK : Blackwell Publishing Ltd 01-07-2008; Blackwell Publishing Ltd; Blackwell
• Subjects: Animal and plant ecology; Animal, plant and microbial ecology; Animals; Autoecology; Biological and medical sciences; diet breadth; Fundamental and applied biological sciences. Psychology; Genetics of eukaryotes. Biological and molecular evolution; haplotypes; Invertebrata; Lepidoptera; maize; mitochondrial gene; Noctuidae; pest management; Poaceae; Population genetics, reproduction patterns; population structure; Protozoa. Invertebrata; Sesamia calamistis; Sorghum; wild hosts; Zea mays; Kenya; Africa; Monocotyledones; Genetic variability; Insecta; Poaceae; Mitochondrial DNA; Population genetics; Cereal crop; Pest; Gramineae; Host plant; Angiospermae; wild hosts; mitochondrial gene; Haplotype; Zea mays; Sorghum; Population structure; pest management; maize; haplotypes; Cytochrome b; Diet; Animal plant relation; Arthropoda; Lepidoptera; Host range; Spermatophyta; Noctuidae; diet breadth; Invertebrata
• ISSN: 0013-8703; 1570-7458
• DOI: 10.1111/j.1570-7458.2008.00735.x

Sesamia calamistis Hampson (Lepidoptera: Noctuidae) is one of the indigenous stem borer pests associated with maize (Zea mays L.) and sorghum [Sorghum bicolor (L.) Moench] (both Poaceae) in Africa. Its pest status varies across the continent and this has been attributed to variation in diet breadth and ecological preferences among populations. Its larvae were found on 12 plant species during a study initiated at four sites (Muhaka, Mtito Andei, Kakamega, and Suam) in Kenya to estimate its diet breadth and genetic population structure. Ten of the infested plant species belonged to the family Poaceae [Echinochloa haploclada (Stapf) Stapf, Eleusine corocana L., Eleusine jaegeri Pilg., Panicum deustum Thunb, Panicum maximum Jacquin, Pennisetum purpureum Schumacher, Setaria verticillata (L.) P. Beauv., Sorghum arundinaceum (Desvaux) Stapf, S. bicolor, and Z. mays]; the other two were Cyperaceae: Cyperus distans L. and Cyperus dives Delile. Combined with collections from other African countries (Uganda, South Africa, Benin, Ghana, Nigeria, and Togo), comparisons of partial cytochrome b sequences revealed the presence of 68 haplotypes that differentiated into clades I and II. In Kenya, the two clades colonized different regions, except in Mtito Andei where they co-existed. Individuals from Mtito Andei could be separated based on their host plants: clade I with 14 haplotypes was found mainly on maize (78.6%), whereas clade II with 10 haplotypes was found mainly among wild host plants (63.6%). Detection of divergence among these clades with cytochrome b suggests that their evolutionary separation may have taken place about one million years ago. This article discusses the potential implication of this differentiation for the management of S. calamistis as a pest of maize and sorghum in Africa.