AJPS  Vol.9 No.12 , November 2018
Susceptible and Glyphosate-Resistant Palmer Amaranth (Amaranthus palmeri) Response to Glyphosate Using C14 as a Tracer: Retention, Uptake, and Translocation
ABSTRACT
The foliar retention, absorption, translocation, and diffusion of glyphosate in glyphosate resistant-(R) and susceptible (S)-Palmer amaranth populations from seed collected in Georgia in 2007 were examined. The R population of Palmer amaranth had an elevated copy number of the EPSPS gene conferring the mechanism of resistance. When applications of 14C-glyphosate to a single leaf followed entire plant treatment with glyphosate, the distribution percentages were similar for R and S for the above and below treated leaves when harvested at 1, 6, 12, 24, and 48 hours after treatment (HAT). There were initially no differences between R and S at 1 HAT with an average of 8% absorption for both biotypes. However, data indicated that glyphosate absorption increased for R-Palmer amaranth reaching 41% within 6 HAT and was significantly different (P = 0.01) from the 28% absorbed by S-Palmer amaranth. Glyphosate resistant and susceptible Palmer amaranth averaged 44% 14C-glyphosate absorption by 24 HAT. There were no differences for 14C-glyphosate Bq/mg of plant tissue between R and S for the above the treated leaf and below the treated leaf portions of plants at 1, 6, 12, 24, or 48 HAT. However, root accumulation of 14C-glyphosate in plant tissue was significantly greater by 12 HAT for the roots of R (1.21 Bq/mg) than for S (0.51 Bq/mg). The treated leaf of the R-Palmer amaranth plants exhibited greater translocation of 14C-glyphosate in Bq/mg of tissue than the susceptible over time, indicating no detrimental effect or cost of fitness due to EPSPS gene amplification. Additionally, there were no differences in glyphosate retention in leaf discs assays between R and S biotypes. In spite of an average of 6.5 Bq efflux out of R and S leaf discs after 15 minute, only 0.4 Bq was retained after 150 minutes. Glyphosate was not retained over time in the leaf discs for R and S, and there were no biotype differences within bathing times. However, the rate of efflux (the slope of the curves) was greater for the R biotype. These data support the reported gene amplification non-target site glyphosate resistance mechanism in Palmer amaranth.
Cite this paper
Grey, T. and Shilling, D. (2018) Susceptible and Glyphosate-Resistant Palmer Amaranth (Amaranthus palmeri) Response to Glyphosate Using C14 as a Tracer: Retention, Uptake, and Translocation. American Journal of Plant Sciences, 9, 2359-2370. doi: 10.4236/ajps.2018.912171.
References
[1]   Heap, I. (2018) The International Survey of Herbicide Resistant Weeds.
http://www.weedscience.org

[2]   Culpepper, A.S., Grey, T.L., Vencill, W.K., Kichler, J.M., Webster, T.M., Brown, S.M., York, A.C., Davis, J.W. and Hanna, W.W. (2006) Glyphosate-Resistant Palmer Amaranth (Amaranthus palmeri) Confirmed in Georgia. Weed Science, 54, 620-626.
https://doi.org/10.1614/WS-06-001R.1

[3]   Webster, T.M. and Sosnoskie, L.M. (2010) Loss of Glyphosate Efficacy: A Changing Weed Spectrum in Georgia Cotton. Weed Science, 58, 73-79.
https://doi.org/10.1614/WS-09-058.1

[4]   Nichols, R.L., Bond, J., Culpepper, A.S., Dodds, D., et al. (2009) Glyphosate-Resistant Palmer Amaranth Spreads in the Southern US. Resistant Pest Management Newsletter, 18, 8-10.

[5]   Webster, T.M. and Nichols, R.L. (2012) Changes in the Prevalence of Weed Species in the Major Agronomic Crops of the Southern United States: 1994/1995 to 2008/2009. Weed Science, 60, 145-157.
https://doi.org/10.1614/WS-D-11-00092.1

[6]   Webster, T.M. (2013) Weed Survey—Southern States: Grass Crops Subsection. Proceedings of the Southern Weed Science Society 66th Annual Meeting, Houston, TX, 28-30 January 2013, 275-287.
http://www.swss.ws/publications/weed-surveys/

[7]   Gaines, T.A., Zhangb, W., Wang, D., Bukun, B., Chisholm, S., Shaner, D., Nissen, S., Patzoldt, W., Tranel, P., Culpepper, A., Grey, T.L., Webster, T.M., Vencill, W.D., Sammons, R.D., Jiang, J., Preston C., Leach, J. and Westra, P. (2010) Gene Amplification Confers Glyphosate Resistance in Amaranthus palmeri. PNAS, 107, 1029-1034.
https://doi.org/10.1073/pnas.0906649107

[8]   Simarmata, M., Kaufmann, J. and Penner, D. (2003) Potential Basis of Glyphosate Resistance in California Rigid Ryegrass (Lolium rigidum). Weed Science, 51, 678-682.
https://doi.org/10.1614/P2002-124

[9]   Feng, P.C., Tran, M., Chiu, T., Sammons, R.D., Heck, G. and Jacob, C. (2004) Investigation into Glyphosate-Resistant Horseweed (Conyza canadensis): Retention, Uptake, Translocation, and Metabolism. Weed Science, 52, 498-505.
https://doi.org/10.1614/WS-03-137R

[10]   Li, J., Smeda, R., Sellers, B. and Johnson, W. (2005) Influence of Formulation and Glyphosate Salt on Absorption and Translocation in Three Annual Weeds. Weed Science, 53, 153-159.
https://doi.org/10.1614/WS-03-075R1

[11]   Chase, C.A., Bewick, T. and Shilling, D.G. (1998) Characterization of Paraquat Resistance in Solanum americanum Mill. I. Paraquat Uptake, Translocation, and Compartmentalization. Pesticide Biochemistry and Physiology, 60, 13-22.
https://doi.org/10.1006/pest.1998.2328

[12]   Cutts III, G.S., Lee, R., Grey, T.L., Tubbs, S., Vencill, W.K., Webster, T.M. and Anderson, W. (2011) Herbicide Effect on Napiergrass (Pennisetum purpureum) Control. Weed Science, 59, 255-262.
https://doi.org/10.1614/WS-D-10-00130.1

[13]   Wiersma, A.T., Gaines, T.A., Preston, C., Hamilton, J.P., Giacomini, D., Buell, C.R., Leach, J.E. and Westra, P. (2015) Gene Amplification of 5-Enol-pyruvylshikimate-3-phosphat Synthase in Glyphosate-Resistant Kochia scoparia. Planta, 241, 463-474.
https://doi.org/10.1007/s00425-014-2197-9

[14]   Powles, S.P. (2010) Gene Amplification Delivers Glyphosate-Resistant Weed Evolution. PNAS, 107, 955-956.
https://doi.org/10.1073/pnas.0913433107

[15]   Geiger, D.R. and Bestman, H. (1990) Self-Limiting of Herbicide Mobility by Phytotoxic Action. Weed Science, 38, 324-329.

[16]   Geiger, D.R., Shieh, W. and Fuchs, M. (1999) Causes of Self-Limited Translocation of Glyphosate in Beta vulgaris Plants. Pesticide Biochemistry and Physiology, 64, 1245-133.
https://doi.org/10.1006/pest.1999.2419

[17]   Powles, B. and Preston, C. (2006) Evolved Glyphosate Resistance in Plants: Biochemical and Genetic Basis of Resistance. Weed Technology, 20, 282-289.
https://doi.org/10.1614/WT-04-142R.1

[18]   Li, J., Peng, Q., Han, H., Nyporko, A., Kulynych, T., Yu, Q. and Powles, S. (2018) Glyphosate Resistance in Tridax procumbensvia a Novel EPSPS Thr-102-Ser Substitution. Journal of Agriculture Food Chemistry, 66, 7880-7888.
https://pubsdc3.acs.org/doi/full/10.1021/acs.jafc.8b01651
https://doi.org/10.1021/acs.jafc.8b01651

[19]   Vila-Aiub, M.M., Goh, S.S., Gaines, T.A., Han, H., Busi, R., Yu, Q. and Powles, S.B. (2014) No Fitness Cost of Glyphosate Resistance Endowed by Massive EPSPS Gene Amplification in Amaranthus palmeri. Planta, 239, 793-801.
https://link.springer.com/article/10.1007/s00425-013-2022-x
https://doi.org/10.1007/s00425-013-2022-x

[20]   Wakelin, A.M., Lorraine-Colwill, D. and Preston, C. (2004) Glyphosate Resistance in Four Different Populations of Lolium rigidum Is Associated with Reduced Translocation of Glyphosate to Meristematic Zones. Weed Research, 44, 453-459.
https://doi.org/10.1111/j.1365-3180.2004.00421.x

[21]   Pline-Srnic, W. (2006) Physilogical Mechanisms of Glyphosate Resistance. Weed Technology, 20, 290-300.
https://doi.org/10.1614/WT-04-131R.1

 
 
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