| dc.contributor.author | Tindo, M. |
| dc.contributor.author | Doumtsop, A. |
| dc.contributor.author | Goergen, Georg E. |
| dc.contributor.author | Hanna, R. |
| dc.date.accessioned | 2019-12-04T11:18:35Z |
| dc.date.available | 2019-12-04T11:18:35Z |
| dc.date.issued | 2006 |
| dc.identifier.citation | Tindo, M., Doumtsop, A., Goergen, G. & Hanna, R. (2006). Morphological description and illustration of female developmental stages of Stictococcus vayssierei (Homoptera: Stictococcidae). International Journal of Tropical Insect Science, 26(2), 126-133. |
| dc.identifier.issn | 1742-7584 |
| dc.identifier.uri | https://hdl.handle.net/20.500.12478/3257 |
| dc.description.abstract | The African root and tuber scale Stictococcus vayssierei Richard is the only known hypogeal species of the family Stictococcidae. Its wide range of host plants together with concurrently field observed differences in host preference provided evidence of polyphagy or the involvement of more than a single-scale species. To establish the baseline information for future taxonomic studies, newly emerged larvae were collected from infested cassava from three sites in the humid forest zone of southern Cameroon. A glass binocular magnifier was used to observe morphological changes of live individuals and slide-mounted individuals of all developmental stages were examined with a compound microscope. Stictococcus vayssierei females went through three developmental stages—two larval instars and an adult stage. The first and second instars were purple-red, while the adult was brown. Body size and the degree of sclerotization of the dorsal line increased in each developmental stage. White waxy secretions on the basal periphery of the second instar, and both dorsum and periphery of the adults, distinguished them from the first instar, which lacks the white waxy secretions. On slide-mounted specimens, certain aspects of the anal complex (i.e. number of opercular plates and -setae) were found to be the most discriminating features of S. vayssierei life stages. These results are useful for further studies on the diversity of subterranean stictoccocid scales. |
| dc.description.abstract | La cochenille Africaine des plantes it racines et tubercules Stictococcus vayssierei Richard est l'unique espece souterraine decrite appartenant it la farnille des Stictococcidae. La large gamme des plantes attaquees ainsi que les differences de preference observees suggerent l'implication de plus d'une espece de cochenille hypogee. Pour reunir des informations de base pouvant permettre une prochaine etude taxinornique, des larves femelles nouvellement pondues ont ete collectees sur des tiges de manioc infestees provenant de trois locaLites de la region de foret hum ide du sud Cameroun. Les changements morphologiques pendant Ie developpement ont ete observes a l'aide d'une loupe binocuJaire et d'un microscope apres montage entre lames et lamelles des echantillons de chaque stade de developpement. Le developpement des femelles de S. vayssierei passe par trois stades dont deux stades larvaires et un stade adulte. Le premier et Ie deuxieme stade sont de couleur rouge pourpre alors que Ie troisieme est de couJeur marron. En plus de (,augmentation de la taille, on constate au cours du developpement la sclerotisation de I'anneau anal et de la ligne dorsale. On note egalement la presence de secretions cireuses blanchatres pres de la peripherie basale du deuxieme stade et sur la cuticuJe dorsale du troisieme stade, ce qui les distingue du premier stade qui ne presente pas de secretions cireuses blanchatres. Cependant, sur les echantillons montes entre lames et lamelles, il apparait que Ie nombre de plaques et de soies operculaires presentes sur Ie complexe anal sont les caracteres les plus discriminants des stades larvaires de S. vayssierei. Ces resultats sont indispensables pour entamer ('etude de la diversite des Stictococcidae hypogees. |
| dc.description.sponsorship | International Fund for Agricultural Development |
| dc.description.sponsorship | Austrian Development Agency |
| dc.language.iso | en |
| dc.language.iso | fr |
| dc.subject | Development |
| dc.subject | Hypogeal |
| dc.subject | Morphology |
| dc.subject | Pests |
| dc.subject | Stictococcidae |
| dc.subject | Stictococcus Vayssierei |
| dc.subject | Root |
| dc.subject | Tuber |
| dc.title | Morphological description and illustration of the female developmental stages of Stictococcus vayssierei (Homoptera: Stictoccocidae) |
| dc.type | Journal Article |
| dc.description.version | Peer Review |
| cg.contributor.affiliation | International Institute of Tropical Agriculture |
| cg.contributor.affiliation | University of Douala |
| cg.coverage.region | Africa |
| cg.coverage.region | Central Africa |
| cg.coverage.country | Cameroon |
| cg.isijournal | ISI Journal |
| cg.authorship.types | CGIAR and developing country institute |
| cg.iitasubject | Pests Of Plants |
| cg.iitasubject | Cassava |
| cg.iitasubject | Climate Change |
| cg.accessibilitystatus | Limited Access |
| local.dspaceid | 94931 |
| cg.identifier.doi | http://dx.doi.org/10.1079/IJT2006109 |
