Rapid genetic turnover in populations of the insect pestBemisia tabaciMiddle East: Asia Minor 1 in an agricultural landscape

Abstract

Organisms differ greatly in dispersal ability, and landscapes differ in amenability to an organism's movement. Thus, landscape structure and heterogeneity can affect genetic composition of populations. While many agricultural pests are known for their ability to disperse rapidly, it is unclear how fast and over what spatial scale insect pests might respond to the temporally dynamic agricultural landscapes they inhabit. We used population genetic analyses of a severe crop pest, a member of the Bemisia tabaci (Hemiptera: Sternorrhyncha: Aleyrodoidea: Aleyrodidea) cryptic species complex known as Middle East-Asia Minor 1 (commonly known as biotype B), to estimate spatial and temporal genetic diversity over four months of the 2006-2007 summer growing season. We examined 559 individuals from eight sites, which were scored for eight microsatellite loci. Temporal genetic structure greatly exceeded spatial structure. There was significant temporal change in local genetic composition from the beginning to the end of the season accompanied by heterozygote deficits and inbreeding. This temporal structure suggests entire cohorts of pests can occupy a large and variable agricultural landscape but are rapidly replaced. These rapid genetic fluctuations reinforce the concept that agricultural landscapes are dynamic mosaics in time and space and may contribute to better decisions for pest and insecticide resistance management.

Demographic Trends in Mixed <I>Bemisia tabaci</I> (Hemiptera: Aleyrodidae) Cryptic Species Populations in Commercial Poinsettia Under Biological Control- and Insecticide-Based Management

“…Our data suggest that MEAM1 is capable of displacing Mediterranean populations in a greenhouse environment, similar to observations in both laboratory populations and in the Þeld (Liu et al 2007, Crowder et al 2010, Dinsdale et al 2012, Luan et al 2013). This trend is evident in the biological control-managed greenhouses, as indicated by our inability to detect any Mediterranean individuals after 29 July in the seasonal data set.…”

Spatial Genetic Heterogeneity in Populations of a Newly Invasive Whitefly in China Revealed by a Nation-Wide Field Survey

“…A third possibility would include both multiple introductions and rapid evolution. With regard to rapid evolution, both genetic drift and natural selection (from biotic interactions and abiotic factors in the new environment) may result in genetic heterogeneity of the introduced populations [33]–[36]. For example, the application of insecticides can enhance genetic differentiation by resulting in bottleneck effects [34]–[36].…”

“…Although the other five clusters are composed of single populations, each from only one province, the five clusters do not indicate that gene flow between these provinces is limited. The five single-population clusters could be explained by rapid genetic turnover of the B. tabaci Q populations in these regions, because a recent study documented significant temporal change in local genetic composition accompanied by heterozygosity deficits and inbreeding in B. tabaci B [33].…”

Insecticide resistance status of Bemisia tabaci MEAM1 (Hemiptera: Aleyrodidae) in Australian cotton production valleys

“…In Australia, B. tabaci MEAM1 was first detected in 1994 (Gunning et al ) and is now widely distributed, having displaced one of the native Australian (AUSI) species (Liu et al ; Luan et al ). It is now considered a major pest affecting many crops, particularly vegetables, legumes and cotton (Brier et al ; De Barro et al ; Dinsdale et al ; Sequeira and Reid ; Wilson et al ).…”

“…It is now considered a major pest affecting many crops, particularly vegetables, legumes and cotton (Brier et al 2008;De Barro et al 2005;Dinsdale et al 2012;Sequeira and Reid 2019;Wilson et al 2013).…”