9 research outputs found
Phylogenetic diversity of cassava green mite, Mononychellus progresivus from different geographical sites in East Africa
Cassava green mite (CGM) of the Mononychellus genus is an invasive
species in Africa, introduced from South America. Its phylogenetic
diversity over geographical localities has never been assessed in East
Africa, where mite density dynamics oscillate from few individuals to a
peak of hundreds. The objective of this study was to determine CGM
species comparative phylogenetic diversity from seven distinct
geographical sites in East Africa. Six sites were sampled for CGM
races, two samples from each country. DNA was extracted on internal
transcribed spacer 2 (ITS2) and cytochrome oxidase subunit I (COI), and
compared for phylogenetic variations of CGM from different locations of
East African region. A comparative search from the NCBI Gene bank
resulted into identical species nucleotides from Congo and Benin.
Sequences from the two sites in Kenya were 99-100% similar to CGM
nucleotide from the Congo-Benin accessions (X79902.1) on ITS2 gene
region. On COI, a 98-99% site sequences similarity was observed on M.
progresivus accession X79901.1. A closely related divergence of
specimens collected from Tanzania and Uganda was determined. Both
Uganda and Tanzania had 99% match to X79901.1 on COI region. Similarly,
the Uganda and Tanzania samples had 99% match to emb/X79902.1 on the
18Sr RNA region. The CGM sequence from coastal Kenya had the highest
phylogenetic divergence from the Congo-Benin sequences. A small
biogeographic phylogenetic divergence (0-1%) was evident from the
analyses among the six collection sites. The results confirm M.
progresivus identity in East Africa it also indicates intra-species
phylogenetic variations on the COI gene region of interest.L\u2019acarien vert du manioc (CGM) du genre Mononychellus est
espece invasive Introduite de l\u2019Amerique du Sud en Afrique. Sa
diversite phyllogenetique au sein et entre les localites n\u2019a
jamais ete evaluee en Afrique de l\u2019Est, ou la densite
d\u2019acarien varie de quelques individus a plusieurs centaines.
L\u2019objectif de cette etude etait de determiner la diversite
phyllogenetiques des especes CGM et de comparer sept sites
geographiquement differents en Afrique de l\u2019Est. six sites ont
ete echantillonnes pour des races de CGM, a raison de deux echantillons
par pays. De l\u2019AND a ete extrait sur l\u2019espaceur interne
transcrit 2 (ITS2) et sous-unite I de cytochrome oxidase (COI), ces
echantillons ont ete compares pour les variations phyllogenetiques de
CGM provenant de localites differentes de la region Est Africaine. Une
etude comparee a la banque de gene de NCBI a revele des especes
identiques en provenance de Congo et du Benin, de point de vue de leur
nucleotides. Des sequences provenant des deux sites au Kenya ont exhibe
99-100% de similarite avec les nucleotides de CGM provenant des
accessions Congo-Benin (X79902.1) sur la region genetique ITS2. Sur
COI, une similarite de 98-99% a ete observee sur l\u2019accession M.
progresivus X79901.1. Une divergence de sujets genetiquement proches
a ete observe chez des specimens collectes en Tanzannie et en Ouganda.
Ouganda et Tanzanie ont exhibe 99% de similitude a X79901.1 sur la
region COI. De meme, les echantillons provenant de Ouganda et de
Tanzannie presentaient 99% de similitude avec emb/X79902.1 sur la
region 18Sr RNA. La sequence de CGM provenant de cote kenyane avait la
divergence phyllogenique la plus elevee d\u2019avec les sequences
Congo-Benin. Une legere divergence phyllogenetique geographiaque (0-1%)
a ete note des analyses dans les sites de collection. Les resultats
conferment l\u2019identite de M. progresivus identity en Afrique de
l\u2019Est. l\u2019etude a aussi revele des variations
phyllogenetiques sur la region de gene d\u2019interet COI