Title: Climate suitability analyses compare the distributions
of invasive knotweeds in Europe and North America with the source
localities of their introduced biological control agents.
Authors: Jeremy C. Andersen, and Joseph S. Elkinton
Affiliations: Department of Environmental Conservation, 160
Holdsworth Way, Room 204 Holdsworth Hall, University of Massachusetts
Amherst, Amherst, MA 01003
Running Title: Climate suitability of knotweed biological
control
Abstract: Climate suitability analyses based on ecological
niche modeling provide a powerful tool for biological control
practitioners to assess the likelihood of establishment of different
candidate agents prior to their introduction in the field. These same
analyses could also be performed to understand why some agents establish
more easily than others. The release of three strains of Aphalaraitadori (Shinji) (Hemiptera: Pysllidae), each from a different
source locality in Japan, for the biological control of invasive
knotweed species, Reynoutria spp. Houtt. (Caryophyllales:
Polygonaceae), provides an important opportunity to compare the utility
of climate suitability analyses for identifying potential climate-based
limitations for successful biological control introductions. Here we
predict climate suitability envelopes for three target species of
knotweed in Europe and two target species of knotweed in North America
and compare these suitability estimates for each of these species to the
source localities of each A. itadori strain. We find that source
locality of one strain, the Kyushu strain, has little-to-no suitability
compared to other locations in Japan based on knotweed records from
Europe, supporting an earlier study based on North American Japanese
knotweed records. The source locality of a second strain, the Murakami
strain, was predicted to have medium-to-high suitability based on
records of knotweeds from North America. In contrast, European records
of R. × bohemica Chrtek & Chrtková and R.
sachalinensis (F. Schmidt) Nakai predicted no suitability for this
locality compared to other locations in Japan, while European records
for R. japonica Houtt. predicted low suitability. The source
locality of the final strain, the Hokkaido strain, was predicted as
having medium-to-high suitability based on knotweed records of all
examined species from both North America and Europe.
Keywords: Environmental Niche Modeling, classical biological
control, genotype x environment interactions, Reynoutria,
Fallopia