Submitted to: Weed Technology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 12/6/2012
Publication Date: 1/28/2013
Citation: Anderson, R.L. 2013. Possible causes of dry pea synergy to corn. Weed Technology. 26:438-442.
Interpretive Summary: Producers have long noted that crop rotation can improve crop yield. In our studies, we have found that in addition to the rotation effect, some crops can improve growth efficiency of following crops. For example, corn yields 15% more following dry pea compared with either soybean or spring wheat as a preceding crop. This yield gain occurs with the same resource supply; corn produces more grain by using resources such as nutrient or water more efficiently. Improved growth efficiency also increases corn tolerance to weeds, reducing yield loss due to weed interference. This unique interaction between dry pea and corn may help producers reduce herbicide use in crop production.
Technical Abstract: Dry pea improves corn yield and tolerance to weed interference compared with soybean, spring wheat, or canola as preceding crops. To understand this synergy between dry pea and corn, we examined growth and nutrient concentration of corn following dry pea or soybean in sequence. Each corn plot was split into weed-free and weed-infested subplots, with foxtail millet established at one density to provide uniform weed interference. Compared with soybean, dry pea improved corn grain yield 10% in weed-free conditions and corn tolerance to weed interference more than twofold. Dry pea synergy to corn in weed-free conditions was not related to differences in corn development, height, or nutrient status of corn seedlings. When foxtail millet was present, dry pea increased corn height and rate of development late in the growing season compared with soybean. Improved corn tolerance to weed interference was not related to seedling emergence or growth of foxtail millet, as these parameters did not vary with preceding crop. Other biological factors must be involved in dry pea synergy to corn.