Microsatellites Uncover Multiple Introductions of Clonal Giant Reed (Arundo donax)

Abstract

Giant reed (Arundo donax) is an invasive weed that is native to the Old World. Tens of thousands of hectares of riparian habitat in the Rio Grande Basin (RGB) in Texas and Mexico have been heavily affected by invasions of Arundo. Additionally, many other watersheds across the southwestern United States have also been affected. Giant reed is being targeted for biological control because it displaces native vegetation and consumes water that could potentially be used for agricultural and municipal purposes, especially in areas with limited access to water. Finding the best-adapted insects for biological control involves locating the origin(s) of this plant. To narrow down the proximal source(s) of invasion of giant reed in the RGB, 10 microsatellite markers were developed. An analysis of 203 Old World and 159 North American plants, with an emphasis on the RGB, indicated a reduction in the allelic diversity in the introduced range compared with the Old World. Clonal assignment, neighbor joining, principal coordinates analyses, and STRUCTURE analyses were consistent and implied multiple introductions in North America, with one (likely clonal) lineage responsible for the invasion of the RGB, northern Mexico, and other parts of the southwestern United States. Although no identical matches with the RGB lineage were found in the Old World, several close matches were found on the Mediterranean coast of Spain.

Multiple evolutionary lineages detected in giant reed (Arundo donax L.): Applied and evolutionary perspectives

“…Only recently, giant reed spread from the Mediterranean basin to USA (Hardion et al, ; Mariani et al, ) and to Africa (Canavan, Paterson, & Hill, ) through human activity. It needs to be underlined that, because human‐mediated dispersal may have strongly influenced the distribution of current lineages, as it could be the case of the possible multiple introduction in North America and Australia (Malone et al, ; Tarin et al, ), further investigations of the processes involved in A. donax expansion are required.…”

“…Molecular studies have investigated the genetic relationship within A. donax , suggesting an Asian origin of the species (Hardion et al, ; Mariani et al, ). Giant reed has likely spread from Asia to other continents and only recently it has increased its genetic diversity due to multiple introduction events (Malone, Virtue, Williams, & Preston, ; Tarin et al, ). Moreover, Hardion et al () showed a relevant plastid genetic variability in some geographic areas, but no specific hypothesis about the delimitation of lineages has been proposed.…”

Nota sobre los primeros registros históricos de dos plantas invasoras en la península de Baja California: crónica del misionero jesuita Miguel del Barco

“…Tarin et al (2013) detectaron seis conjuntos clonales en Norteamérica, uno de ellos con amplia distribución geográfica que incluye México, Texas y California. Todos los individuos analizados de México (Durango, Zacatecas, Veracruz y Quintana Roo) pertenecieron al mismo grupo genético (Tarin et al, 2013). En 1820 el carrizo ya era abundante en el río Los Ángeles, California (Dudley, 2000).…”

“…Según Greenlee (1992) fue llevado a California por los misioneros españoles, pero otros autores consideran que se introdujo a principio del siglo XIX para control de la erosión en canales de drenaje (Bell, 1997). El registro de del Barco sugiere que la relación entre las poblaciones de México y California encontradas por Tarin et al (2013) puede tener como conexión aquellas introducidas en la península de Baja California.…”

Tripius gyraloura n. sp. (Aphelenchoidea: Sphaerulariidae) parasitic in the gall midge Lasioptera donacis Coutin (Diptera: Cecidomyiidae)

“…The Old World giant reed, Arundo donax (L.), native to the Mediterranean, was introduced into North America in the 16th Century (Tarin et al, 2013) and since then has become a noxious weed. Attempts have and are being made to find insects that feed on this invasive plant and may be useful in reducing its negative impacts (Seawright et al, 2009).…”