Hostname: page-component-586b7cd67f-t7czq Total loading time: 0 Render date: 2024-11-25T19:42:27.690Z Has data issue: false hasContentIssue false

Johnsongrass (Sorghum halepense) Competition in Soybeans (Glycine max)

Published online by Cambridge University Press:  12 June 2017

C. S. Williams
Affiliation:
Plant and Soil Sci. Dep., Univ. of Tenn., West Tenn. Agric. Exp. Stn., Jackson, TN 38301
Robert M. Hayes
Affiliation:
Plant and Soil Sci. Dep., Univ. of Tenn., West Tenn. Agric. Exp. Stn., Jackson, TN 38301

Abstract

Johnsongrass [Sorghum halepense (L.) Pers., ♯3 SORHA] dry weight and johnsongrass culms/ha at harvest were more negatively correlated with soybean yield reductions than the number of johnsongrass plants/ha present at 4 to 6 weeks after planting. However, plant numbers can be determined in sufficient time to implement control measures to prevent yield reduction. Prediction equations for estimating soybean yield at various johnsongrass populations are Ŷ = 1776 + 424e-.023x2 for 0.25-m row spacing and Ŷ = 1668 + 643e-.004x2 for the 1-m row spacing, where Ŷ = estimated yield and x = the number of johnsongrass plants/10 m2. Full-season heavy johnsongrass competition reduced soybean yields from 59 to 88%. Soybeans in the 1-m row spacing were more competitive with low johnsongrass densities than in the 0.25-m row spacing. The johnsongrass-free requirement for soybeans was 4 weeks after planting and soybeans could not tolerate heavy infestations of johnsongrass for more than 5 weeks without loss in yield potential. Application of sethoxydim {2-[1-(ethoxyimino)-butyl]-5-[2-ethylthio)propyl]-3-hydroxy-2-cyclohexen-1-one} at 3 or 4 weeks after planting was effective in controlling heavy infestations of johnsongrass and preventing yield reductions due to competition.

Type
Weed Biology and Ecology
Copyright
Copyright © 1984 by the Weed Science Society of America 

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

Literature Cited

1. Barrentine, W. L. 1974. Common cocklebur competition in soybean. Weed Sci. 22:600603.CrossRefGoogle Scholar
2. Black, C. C., Chen, T. M., and Brown, R. H. 1969. Biochemical basis for plant competition. Weed Sci. 17:338344.Google Scholar
3. Bloomberg, J. R., Kirkpatrick, B. L., and Wax, L. M. 1982. Competition of common cocklebur (Xanthium pensylvanicum) with soybean (Glycine max). Weed Sci. 30:507513.Google Scholar
4. Buchanan, G. A. 1977. Weed biology and competition. Pages 2441 in Truelove, B. (ed.). Research Methods in Weed Science. 2nd ed. South. Weed Sci. Soc. Google Scholar
5. Burnside, O. C. and Colville, W. L. 1964. Soybean and weed yields as affected by irrigation, row spacing, tillage and amiben. Weeds 12:107112.CrossRefGoogle Scholar
6. Buntley, G. L. and Bauer, L. L. 1974. Soybean production on some major soils in Tennessee. Univ. of Tenn. Agric. Exp. Stn. Bull. 537. 42 pp.Google Scholar
7. Caviness, C. E. and Taylor, M. 1960. Effect of johnsongrass on soybean yields. Arkansas Farm. Res. 9:2.Google Scholar
8. Chamblee, R. W., Thompson, L. Jr., and Coble, H. D. 1982. Interference of broadleaf signalgrass (Brachiaria platyphylla) in peanuts (Arachis hypogea). Weed Sci. 30:4549.Google Scholar
9. Coble, H. D. and Ritter, R. L. 1978. Pennsylvania smartweed (Polygonum pensylvanicum) interference in soybeans (Glycine max). Weed Sci. 26:556559.CrossRefGoogle Scholar
10. Holm, L. 1969. Weed problems in developing countries. Weed Sci. 17:113118.Google Scholar
11. Horowitz, M. 1973. Competition of Cynodon dactylon, Sorghum halepense, and Cyperus rotundus on cotton and mustard. Exp. Agric. 9:263273.Google Scholar
12. McWhorter, C. G. and Anderson, J. M. 1981. The technical and economic effect of johnsongrass (Sorghum halepense) control in soybeans (Glycine max). Weed Sci. 29:245253.CrossRefGoogle Scholar
13. McWhorter, C. G. and Hartwig, E. E. 1968. Competition of johnsongrass and cocklebur with six soybean varieties. Weed Sci. 20:5659.CrossRefGoogle Scholar
14. Peters, E. J., Gebhardt, M. R., and Stritzke, J. F. 1965. Interrelations of row spacings, cultivations, and herbicides for weed control in soybeans. Weeds 13:285289.Google Scholar
15. Snipes, C. E., Buchanan, G. A., Street, J. E., and McGuire, J. A. 1982. Competition of common cocklebur (Xanthium pensylvanicum) with cotton (Gossypium hirsutum). Weed Sci. 30:553556.CrossRefGoogle Scholar
16. Turlow, D. L. and Buchanan, G. A. 1972. Competition of sicklepod with soybeans. Weed Sci. 20:379384.CrossRefGoogle Scholar
17. Weaver, J. E. and Clements, F. E. 1938. Plant Ecology. McGraw-Hill, New York. 600 pp.Google Scholar
18. Zimdahl, R. L. 1980. Weed-Crop Competition. A review. International Plant Protection Center, Oreg. State Univ., Corvallis. 195 pp.Google Scholar