Genetic diversity of whitefly (Bemisia spp.) on crop and uncultivated plants in Uganda: implications for the control of this devastating pest species complex in Africa
Loading...
Date
2021
Journal Title
Journal ISSN
Volume Title
Publisher
Journal of pest science
Abstract
Over the past three decades, highly increased whitefly (Bemisia tabaci) populations have been observed on the staple food
crop cassava in eastern Africa and associated with ensuing viral disease pandemics and food insecurity. Increased whitefly
numbers have also been observed in other key agricultural crops and weeds. Factors behind the population surges on different
crops and their interrelationships are unclear, although in cassava they have been associated with specific populations within
the Bemisia tabaci species complex known to infest cassava crops in Africa. This study carried out an in-depth survey to
understand the distribution of B. tabaci populations infesting crops and uncultivated plant hosts in Uganda, a centre of origin
for this pest complex. Whitefly samples were collected from 59 identified plant species and 25 unidentified weeds in a countrywide
survey. Identities of 870 individual adult whiteflies were determined through mitochondrial cytochrome oxidase 1
sequences (651 bp) in the 3′ barcode region used for B. tabaci systematics. Sixteen B. tabaci and five related whitefly putative
species were identified based on > 4.0% nucleotide divergence, of which three are proposed as novel B. tabaci putative species
and four as novel closely related whitefly species. The most prevalent whiteflies were classified as B. tabaci MED-ASL
(30.5% of samples), sub-Saharan Africa 1 (SSA1, 22.7%) and Bemisia Uganda1 (12.1%). These species were also indicated
to be the most polyphagous occurring on 33, 40 and 25 identified plant species, respectively. Multiple (≥ 3) whitefly species
occurred on specific crops (bean, eggplant, pumpkin and tomato) and weeds (Sida acuta and Ocimum gratissimum). These
plants may have increased potential to act as reservoirs for mixed infections of whitefly-vectored viruses. Management of
whitefly pest populations in eastern Africa will require an integration of approaches that consider their degree of polyphagy
and a climate that enables the continuous presence of crop and uncultivated plant hosts.
Description
Keywords
Whitefly, Bemisia tabaci, MtCO1, Genetic diversity, Host range, East Africa
Citation
Mugerwa, H., Colvin, J., Alicai, T., Omongo, C. A., Kabaalu, R., Visendi, P., ... & Seal, S. E. (2021). Genetic diversity of whitefly (Bemisia spp.) on crop and uncultivated plants in Uganda: Implications for the control of this devastating pest species complex in Africa. Journal of pest science, 94(4), 1307-1330. https://doi.org/10.1007/s10340-021-01355-6