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Effect of Weed Competition on Sunflowers

Published online by Cambridge University Press:  12 June 2017

B. J. Johnson
B. J. Johnson*
Affiliation:
Georgia Sta., Experiment, Georgia 30212
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Abstract

Sunflowers (Helianthus annuus L.) produced maximum seed yields when kept weed free for a period of 4 to 6 weeks after planting. This was accomplished with one cultivation anytime between 2 and 6 weeks after the early planting in 1969, with two cultivations 2 and 4 weeks or 4 and 6 weeks after the late planting in 1969, and with one cultivation at 4 weeks after either the early or late planting in 1970. The average height of sunflower plants was not influenced by weed competition if weeded at either 2 or 4 weeks after planting, whereas, head and seed size were not affected if weeded at 4 weeks after planting. The oil content of seed was higher in plots with the least amount of weed competition.

Type
Research Article
Information
Weed Science , Volume 19 , Issue 4 , July 1971 , pp. 378 - 380
Copyright
Copyright © Weed Science Society of America 

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References

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