Principal Coordinates Analysis based on diversity revealed by 10 microsatellites markers showing the dispersion of 48 swiddens from three soil types (17 in ADE soils, 14 in floodplain soils and 17 in Oxisols/Utilsols) in six communities along the middle Madeira River.

<p>The two coordinates together explain 65.4% of the variation in the matrix.</p

Map of the middle Madeira River region, Amazonas State, Brazil, showing communities where research was carried out.

<p>The inset map shows the location of the middle Madeira River in Northern South America. Map by Victoria Frausin.</p

Schematic representation of floodplain zones relative to the main channel, lakes and <i>terra firme</i> (non-flooded upland plateaus).

<p><i>Vazante</i> is the local term on the middle Madeira for the banks of the main channel, <i>Restinga</i> for the high levee floodplain and <i>Cacaia</i> for the back-swamp area. Drawn by Victoria Frausin.</p

Farmer-recorded production of 50 kg sacks of manioc flour that would be obtained from approximately 0.5 ha of swidden plot at various localities along the Middle Madeira River, Central Amazonia, Brazil, in 2007–2008.

<p>Superscript characters indicate significant differences in pairwise comparisons using Tukey's HSD test (p<0.05).</p

Number of informants, both total and key individuals for manioc management, number of landraces cultivated, and the ways that farmers manage seedlings at six communities along the middle Madeira River, municipality of Manicoré, Amazonas, Brazil.

<p>Number of informants, both total and key individuals for manioc management, number of landraces cultivated, and the ways that farmers manage seedlings at six communities along the middle Madeira River, municipality of Manicoré, Amazonas, Brazil.</p

Number of individuals, haplotype designation, and genetic diversity for the sampled populations grouped according to geographical origin.

<p>Number of individuals, haplotype designation, and genetic diversity for the sampled populations grouped according to geographical origin.</p

Bayesian phylogenetic tree of <i>H. armigera</i> and <i>H. zea</i> individuals sampled in Brazil.

<p>This phylogenetic tree is based on partial COI haplotype sequences and includes <i>H. assulta</i> and <i>H. gelotopoeon</i> sequences. Numbers near the interior branches indicate posterior probability (×100) values. The outgroup used was <i>Heliothis virescens</i>. <i>H. armigera</i> COI haplotypes and Genbank Accession numbers can be found in <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0113286#pone.0113286.s003" target="_blank">Table S2</a>.</p

Sampling sites for <i>Helicoverpa armigera</i> and <i>Helicoverpa zea</i> in Brazil, including the sites where these insects were sampled for this study, abbreviations, sample sizes for the mitochondrial genes (COI), crops sampled, geographic coordinates, dates sampled, and GenBank Accession.

<p>Sampling sites for <i>Helicoverpa armigera</i> and <i>Helicoverpa zea</i> in Brazil, including the sites where these insects were sampled for this study, abbreviations, sample sizes for the mitochondrial genes (COI), crops sampled, geographic coordinates, dates sampled, and GenBank Accession.</p

Indices of intra-varietal genetic diversity [Observed (<i>H_O</i>) and expected (<i>H_E</i>) heterozygosities, and number of multi-locus genotypes (No. MLGs)] for five bitter manioc landraces cultivated in different soil types in the middle Madeira River region, based on variation detected with 10 microsatellite markers.

<p>Capital letters indicate the MLGs that were present in more than one landrace. Boldfaced letters indicate the most common MLG for a given landrace, while small letters indicate MLGs present at low frequencies.</p

Non-metric multidimensional scaling (NMDS) showing the composition of bitter manioc landraces sampled in fields on Ultisols, Oxisols, Anthropogenic Dark Earths (ADE) and on floodplains along the middle Madeira River (percentage of explanation of the bidimensional model: 35.8%).

<p>Each point represents a bitter manioc field, and its position in the graph is a bidimensional representation of the Bray-Curtis dissimilarity between the fields.</p