Limits...
The geographic mosaic of herbicide resistance evolution in the common morning glory, Ipomoea purpurea: Evidence for resistance hotspots and low genetic differentiation across the landscape.

Kuester A, Chang SM, Baucom RS - Evol Appl (2015)

Bottom Line: We uncovered a mosaic pattern of resistance across the landscape, with some populations exhibiting high-survival postherbicide and other populations showing high death.SSR genotyping revealed little evidence of isolation by distance and very little neutral genetic structure associated with geography.An approximate Bayesian computation (ABC) analysis uncovered evidence for migration and admixture among populations before the widespread use of glyphosate rather than the very recent contemporary gene flow.

View Article: PubMed Central - PubMed

Affiliation: Department of Ecology and Evolutionary Biology, 830 North University, University of Michigan Ann Arbor, MI, USA.

ABSTRACT
Strong human-mediated selection via herbicide application in agroecosystems has repeatedly led to the evolution of resistance in weedy plants. Although resistance can occur among separate populations of a species across the landscape, the spatial scale of resistance in many weeds is often left unexamined. We assessed the potential that resistance to the herbicide glyphosate in the agricultural weed Ipomoea purpurea has evolved independently multiple times across its North American range. We examined both adaptive and neutral genetic variations in 44 populations of I. purpurea by pairing a replicated dose-response greenhouse experiment with SSR genotyping of experimental individuals. We uncovered a mosaic pattern of resistance across the landscape, with some populations exhibiting high-survival postherbicide and other populations showing high death. SSR genotyping revealed little evidence of isolation by distance and very little neutral genetic structure associated with geography. An approximate Bayesian computation (ABC) analysis uncovered evidence for migration and admixture among populations before the widespread use of glyphosate rather than the very recent contemporary gene flow. The pattern of adaptive and neutral genetic variations indicates that resistance in this mixed-mating weed species appears to have evolved in independent hotspots rather than through transmission of resistance alleles across the landscape.

No MeSH data available.


Related in: MedlinePlus

Survival 3 weeks post-RoundUp herbicide application among I. purpurea populations at the rate of (A) 1.7 kg a.i./ha and (B) 3.4 kg a.i/ha. The proportion survival within each population is indicated by color.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
getmorefigures.php?uid=PMC4561571&req=5

fig01: Survival 3 weeks post-RoundUp herbicide application among I. purpurea populations at the rate of (A) 1.7 kg a.i./ha and (B) 3.4 kg a.i/ha. The proportion survival within each population is indicated by color.

Mentions: We collected leaf material and seeds from 44 populations of I. purpurea located within soya, cotton, corn or alfalfa fields selected at random from six states across the Midwestern and Southeastern USA (IN, OH, VA, NC, SC, TN; Fig. 1A, Table S1). We collected between 20 and 40 seeds and leaf material from a single maternal plant every 2 meters at each of our 44 sites until we had sampled from at least 30 individuals per population. Each population was sampled from a discrete agricultural field, which we assume to represent discrete units of selection. Populations were at least 5 km apart.


The geographic mosaic of herbicide resistance evolution in the common morning glory, Ipomoea purpurea: Evidence for resistance hotspots and low genetic differentiation across the landscape.

Kuester A, Chang SM, Baucom RS - Evol Appl (2015)

Survival 3 weeks post-RoundUp herbicide application among I. purpurea populations at the rate of (A) 1.7 kg a.i./ha and (B) 3.4 kg a.i/ha. The proportion survival within each population is indicated by color.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4561571&req=5

fig01: Survival 3 weeks post-RoundUp herbicide application among I. purpurea populations at the rate of (A) 1.7 kg a.i./ha and (B) 3.4 kg a.i/ha. The proportion survival within each population is indicated by color.
Mentions: We collected leaf material and seeds from 44 populations of I. purpurea located within soya, cotton, corn or alfalfa fields selected at random from six states across the Midwestern and Southeastern USA (IN, OH, VA, NC, SC, TN; Fig. 1A, Table S1). We collected between 20 and 40 seeds and leaf material from a single maternal plant every 2 meters at each of our 44 sites until we had sampled from at least 30 individuals per population. Each population was sampled from a discrete agricultural field, which we assume to represent discrete units of selection. Populations were at least 5 km apart.

Bottom Line: We uncovered a mosaic pattern of resistance across the landscape, with some populations exhibiting high-survival postherbicide and other populations showing high death.SSR genotyping revealed little evidence of isolation by distance and very little neutral genetic structure associated with geography.An approximate Bayesian computation (ABC) analysis uncovered evidence for migration and admixture among populations before the widespread use of glyphosate rather than the very recent contemporary gene flow.

View Article: PubMed Central - PubMed

Affiliation: Department of Ecology and Evolutionary Biology, 830 North University, University of Michigan Ann Arbor, MI, USA.

ABSTRACT
Strong human-mediated selection via herbicide application in agroecosystems has repeatedly led to the evolution of resistance in weedy plants. Although resistance can occur among separate populations of a species across the landscape, the spatial scale of resistance in many weeds is often left unexamined. We assessed the potential that resistance to the herbicide glyphosate in the agricultural weed Ipomoea purpurea has evolved independently multiple times across its North American range. We examined both adaptive and neutral genetic variations in 44 populations of I. purpurea by pairing a replicated dose-response greenhouse experiment with SSR genotyping of experimental individuals. We uncovered a mosaic pattern of resistance across the landscape, with some populations exhibiting high-survival postherbicide and other populations showing high death. SSR genotyping revealed little evidence of isolation by distance and very little neutral genetic structure associated with geography. An approximate Bayesian computation (ABC) analysis uncovered evidence for migration and admixture among populations before the widespread use of glyphosate rather than the very recent contemporary gene flow. The pattern of adaptive and neutral genetic variations indicates that resistance in this mixed-mating weed species appears to have evolved in independent hotspots rather than through transmission of resistance alleles across the landscape.

No MeSH data available.


Related in: MedlinePlus