Submitted to: Weed Science
Publication Type: Peer reviewed journal
Publication Acceptance Date: 5/23/2006
Publication Date: 9/21/2006
Citation: Williams, M., Masiunas, J.B. 2006. Functional relationships between giant ragweed (Ambrosia trifida L.) interference and sweet corn yield and ear traits. Weed Science. 54:948-953. Interpretive Summary: Improvements in weed management systems in crop production rely on detailed understanding of how the crop is negatively affected by weed interference. For many horticultural crops, weed interference has the potential to influence several crop quality traits besides yield. Studies were conducted over four site-years to quantify relationships between giant ragweed density and sweet corn yield and ear traits. Although sweet corn is the same botanical species as field corn, sweet corn is far more susceptible to losses due to weeds. Also, many ear traits responsible for crop quality were also affected by weed interference. This research impacts future studies of weed-sweet corn interactions, because selection of crop response variables will often need to consider traits beyond mass of ears.
Technical Abstract: Field experiments were conducted to quantify functional relationships between giant ragweed density and sweet corn yield and ear traits. A rectangular hyperbolic model was fit to yield loss measured in terms of ear mass, appropriate for the processing industry, and boxes of ears, relevant to the fresh market industry. The initial slope of the hyperbolic yield loss function, which describes the linear portion of yield loss as weed density approaches zero, was 119 for loss of ear mass and 97 for loss of boxes of ears. Coupled with maximum yield losses of 100%, sweet corn has a poorer tolerance to weed interference compared to previous research in field corn. Furthermore, ten of twelve ear traits including green ear mass, husked ear mass, ear length, filled ear length, ear width, number kernels row-1, number of rows, kernel depth, kernel mass, and kernel moisture content, were significantly affected by giant ragweed interference. Future study of sweet corn/weed interactions may need to consider specific variables for yield and ear traits associated with quality, depending on whether the crop is destined for fresh or processed markets.