Hostname: page-component-586b7cd67f-dsjbd Total loading time: 0 Render date: 2024-11-22T17:25:59.116Z Has data issue: false hasContentIssue false

The Technical and Economic Effects of Johnsongrass (Sorghum halepense) Control in Soybeans (Glycine max)

Published online by Cambridge University Press:  12 June 2017

C. G. McWhorter
Affiliation:
South. Weed Sci. Lab., Sci. Ed. Admin., U.S. Dep. Agric., Stoneville, MS 38776
J. M. Anderson
Affiliation:
Ames Plantation, Univ. of Tennessee, Grand Junction, TN 38039

Abstract

The effect of johnsongrass [Sorghum halepense (L.) Pers.] on soybean [Glycine max (L.) Merr.] yields, grades, and net returns were determined by regression analysis of data from 252 field research plots from 1971 through 1976. Johnsongrass control from 0 to 100% was achieved by various combinations of summer fallow, dalapon (2,2-dichloropropionic acid) as a preplanting application at 8.3 kg/ha, or trifluralin (α,α,α-trifluoro-2,6-dinitro-N,N-dipropyl-p-toluidine) at 0.8 to 1.7 kg/ha incorporated into the soil before planting. Repeated usage of trifluralin at 1.7 kg/ha, either with or without use of summer fallow, provided the most effective and most profitable soybean production. Foreign material in soybean seed samples was about 0.8% with 100% johnsongrass control and nearly 6% with no control. At least 70% johnsongrass control was required to avoid deductions from gross harvested weights caused by seed moisture levels exceeding 13%. Levels of johnsongrass control in excess of 60% tended to increase soybean test weights. With 100% johnsongrass control, about 1.2% damaged soybean seed occurred; whereas, without johnsongrass control, about 1.7% seed damage occurred. The level of johnsongrass control had little effect on the level of split soybean seed at harvest. Failure to control johnsongrass resulted in predicted soybean grades of 4.1; whereas, nearly 100% johnsongrass control was necessary to provide U.S. No. 1 grade soybeans. Soybean yields were increased 4.8 to 6.2% for each 10% increase in johnsongrass control when plots were not fallowed or after fallowing, respectively. Net returns in soybean production were nearly twice as great with 100% johnsongrass control as when johnsongrass was not controlled.

Type
Research Article
Copyright
Copyright © 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. Anderson, J. M. and McWhorter, C. G. 1976. The economics of common cocklebur control in soybean production. Weed Sci. 23:397400.Google Scholar
2. Cooke, F. T. Jr., Anderson, J. M., and Heagler, A. M. 1972. Crop budgets and planning data for major farm enterprises in the Yazoo-Mississippi Delta. Miss. Agric. Exp. Stn. Bull. 794. 56 pp.Google Scholar
3. Draper, N. R. and Smith, H. 1966. Applied Regression Analysis. John Wiley and Sons, Inc., New York. 407 pp.Google Scholar
4. McWhorter, C. G. and Anderson, J. M. 1976. Effectiveness of metribuzin applied preemergence for economical control of common cocklebur in soybeans. Weed Sci. 24:385390.Google Scholar
5. McWhorter, C. G. and Anderson, J. M. 1976. Bentazon applied postemergence for economical control of common cocklebur in soybeans. Weed Sci. 24:391396.Google Scholar
6. McWhorter, C. G. and Anderson, J. M. 1979. Hemp sesbania (Sesbania exaltata) competition in soybeans (Glycine max . Weed Sci. 27:5863.Google Scholar
7. McWhorter, C. G. and Hartwig, E. E. 1965. Effectiveness of preplanting tillage in relation to herbicides in controlling johnsongrass for soybeans production. Agron. J. 57:385389.Google Scholar
8. McWhorter, C. G. and Hartwig, E. E. 1972. Competition of johnsongrass and cocklebur with six soybean varieties. Weed Sci. 20:5659.Google Scholar
9. Parvin, D. W. Jr., Anderson, J. M., Holder, S. H. Jr., and Cooke, F. T. Jr. 1976. Cost of production estimates for major crops, Mississippi Delta, 1976. Miss. Agric. For. Exp. Stn. Bull. 843. 58 pp.Google Scholar
10. Steel, R. G. D. and Torrie, J. H. 1960. Principles and Procedures of Statistics. McGraw-Hill Book Co., Inc., New York. 481 pp.Google Scholar
11. U.S. Department of Agriculture. 1970. Official grain and standards of the United States. Pages 8.18.6 in Official Grain Standards of the United States. Revised ed., U.S. Government Printing Office, Washington, D.C. Google Scholar