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Effects of Temperature and Relative Humidity on the Toxicity of Glyphosate to Bermudagrass (Cynodon dactylon)

Published online by Cambridge University Press:  12 June 2017

T.N. Jordan*
Affiliation:
Delta Branch of the Mississippi Agric. and For. Exp. Stn., Stoneville, MS 38776

Abstract

Glyphosate [N-(phosphonomethyl)glycine] toxicity to bermudagrass [Cynodon dactylon (L.) Pers.] increased significantly with each rate increase from 0.14 to 1.12 kg/ha. Under greenhouse conditions approximately 50% bermudagrass control was obtained at 0.56 kg/ha glyphosate. Visible toxicity and fresh wt of treated plants and regrowth of plants clipped at the soil surface 24 h after treatment were used as indices for penetration and translocation of glyphosate. Visible injury to bermudagrass with 0.56 kg/ha glyphosate was greater at 100% than at 40% relative humidity (RH) at both 22 and 32 C. Fresh wt data indicated that 0.56 kg/ha glyphosate was more toxic at 32 C than at 22 C at 40% RH, but no difference was observed at 100% RH. Less than 10% of the applied 14C-glyphosate penetrated the treated bermudagrass leaf at 22 C and 40% RH; whereas, more than 70% penetrated the treated leaf at 32 C and 100% RH. Five to six times more 14C-label was translocated into the plant at 100% than at 40% RH. Significantly more 14C-label translocated out of the treated leaf and into the plant at 32 C than at 22 C at 40% RH but no significant increase was observed at 100% RH.

Type
Research Article
Copyright
Copyright © 1977 by the Weed Science Society of America 

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References

Literature Cited

1. Burton, G.W. 1967. Bermudagrass. Pages 270280 in Hughes, H.D., Heath, M.E., and Metcalfe, D.S., eds. Forages, the Science of Grassland Agriculture. The Iowa State University Press, Ames, Iowa.Google Scholar
2. Clor, M.A., Crafts, A.S., and Yamaguchi, S. 1962. Effect of high humidity on translocation of foliar-applied labeled compounds in plants. Part I. Plant Physiol. 37:609617.Google Scholar
3. Crafts, A.S. and Yamuguchi, S. 1964. The autoradiography of plant materials. California Agric. Exp. Stn. and Ext. Serv. Manual 35. 143 pp.Google Scholar
4. Dudek, C., Basler, E., and Santelmann, P.W. 1973. Absorption and translocation of terbutryn and propazine. Weed Sci. 21:440442.CrossRefGoogle Scholar
5. Jordan, T.N. and Baker, R.S. 1975. Control of bermudagrass in cotton. Mississippi Agric. For. Stan. Res. Rep. 1(20): looseleaf pub. n.p. Google Scholar
6. Jordan, T.N. and Bridge, R.R. 1975. Selectivity of glyphosate to cotton cultivars, johnsongrass, and bermudagrass. Proc. South. Weed Sci. Soc. 29:5357.Google Scholar
7. McWhorter, C.G. and Jordan, T.N. 1976. Effects of adjuvants and environment on the toxicity of dalapon to johnsongrass. Weed Sci. 24:257260.Google Scholar
8. McWhorter, C.G. and Jordan, T.N. 1976. Factors affecting dalapon absorption and translocation in johnsongrass. Physiol. Plant. 38:166170.Google Scholar
9. Prasad, R., Foy, C.L., and Crafts, A.S. 1967. Effect of relative humidity on absorption and translocation of foliarly-applied dalapon. Weeds 15:149156.CrossRefGoogle Scholar
10. Sheets, T.J. 1961. Uptake and distribution of simazine by oat and cotton seedlings. Weeds 9:13.CrossRefGoogle Scholar
11. Sprankle, P., Meggett, W.F., and Penner, D. 1975. Absorption, action, and translocation of glyphosate. Weed Sci. 23:235240.Google Scholar