title: Phylogenetic Relationships among Whiteflies in the Bemisia tabaci (Gennadius) Species Complex from Major Cassava Growing Areas in Kenya.
abstract: Whiteflies,Bemisia tabaci(Gennadius) are major insect pests that affect many crops such as cassava, tomato, beans, cotton, cucurbits, potato, sweet potato, and ornamental crops.Bemisia tabacitransmits viral diseases, namely cassava mosaic and cassava brown streak diseases, which are the main constraints to cassava production, causing huge losses to many small-scale farmers. The aim of this work was to determine the phylogenetic relationships amongBemisia tabacispecies in major cassava growing areas of Kenya. Surveys were carried out between 2013 and 2015 in major cassava growing areas (Western, Nyanza, Eastern, and Coast regions), for cassava mosaic disease (CMD) and cassava brown streak disease (CBSD). Mitochondrial cytochrome oxidase I (mtCOI-DNA) was used to determine the genetic diversity ofB. tabaci. Phylogenetic trees were constructed using Bayesian methods to understand the genetic diversity across the study regions. Phylogenetic analysis revealed twoB. tabacispecies present in Kenya, sub-Saharan Africa 1 and 2 comprising five distinct clades (A-E) with percent sequence similarity ranging from 97.7 % to 99.5%. Clades B, C, D, and E are predominantly distributed in the Western and Nyanza regions of Kenya whereas clade B is dominantly found along the coast, the eastern region, and parts of Nyanza. OurB. tabaciclade A groups with sub-Saharan Africa 2-(SSA2) recorded a percent sequence similarity of 99.5%. In this study, we also report the identification of SSA2 after a 15 year absence in Kenya. The SSA2 species associated with CMD has been found in the Western region of Kenya bordering Uganda. More information is needed to determine if these species are differentially involved in the epidemiology of the cassava viruses.
authors.affiliation: Department of Biochemistry, Jomo Kenyatta University of Agriculture and Technology, Nairobi P.O. Box 62000-00200, Kenya. mogareduke@gmail.com.
authors.forename: Duke M
authors.initials: DM
authors.lastname: Manani
authors.affiliation: Department of Horticulture, Jomo Kenyatta University of Agriculture and Technology, Nairobi P.O. Box 62000-00200, Kenya. eateka@agr.jkuat.ac.ke.
authors.forename: Elijah M
authors.initials: EM
authors.lastname: Ateka
authors.affiliation: Department of Biochemistry, Jomo Kenyatta University of Agriculture and Technology, Nairobi P.O. Box 62000-00200, Kenya. snyanjom@gmail.com.
authors.forename: Steven R G
authors.initials: SR
authors.lastname: Nyanjom
authors.affiliation: Australian Research Council Centre of Excellence in Plant Energy Biology, The University of Western Australia, Crawley, WA 6009, Australia. laura.boykin@uwa.edu.au.|School of Molecular Sciences, The University of Western Australia, Crawley, WA 6009, Australia. laura.boykin@uwa.edu.au.
authors.forename: Laura M
authors.initials: LM
authors.lastname: Boykin
keywords: Bemisia tabaci; Kenya; cassava; cassava brown streak disease (CBSD); cassava mosaic disease (CMD); genetic diversity; mtCOI