|Wilcut, John - N.C. STATE UNIVERSITY|
Submitted to: Weed Technology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: June 3, 2007
Publication Date: October 1, 2007
Citation: Price, A.J., Wilcut, J.W. 2007. Response of ivyleaf morningglory [(Ipomoea hederacea (L.) Jacq.] to neighboring plants and objects. Weed Technology. 21:922-927. Interpretive Summary: Field observations of morningglory noted that many plants grew out of places of comparable competitive advantage (alleys in field experiments with little or no vegetation) onto neighboring plants or structures that allowed a climbing habitat. Greenhouse and field research were initiated to determine if morningglory grew preferentially toward certain colored structure. Data showed that if morningglory that are located within 46 cm of green corn, 78% of the time they will successfully locate and climb. Because many crops are planted with row spacing of 76 to 90 cm, the success of morningglory to locate and climb a crop readily illustrates reasons why control of morningglories is critical. Also, these data show that as morningglory successfully locate and climb structure, seed production increases.
Technical Abstract: Field observations of morningglory (Ipomoea spp.) noted that many plants grew out of places of comparable competitive advantage (alleys in field experiments with little or no vegetation) onto neighboring plants or structures that allowed a climbing habitat. A total of 223 morningglory plants growing in rows and row middles in a 121 m2 area within established corn research plots containing no other weeds revealed that of the total morningglory plants surveyed, 68% that were large enough climbed up corn plants. More significant, of the 152 climbing morningglory, 96% had grown to the row closest in proximity instead of growing across the row middle. Greenhouse and field research were initiated to determine if morningglory grew preferentially toward certain colored structure or green corn plants. Greenhouse grown ivyleaf morningglory displayed varying frequency of locating and climbing growth toward black (17%), blue (58%), green (75%), red (58%), yellow (67%), white (75%) stakes, or corn (92%). Pots containing black stakes had the fewest climbing morningglory. In the field study, fewer ivyleaf morningglory climbed black structure compared to white or green-colored structure or green corn. The morningglories’ initial planting distance from structure or green corn was also significant for percentage of ivyleaf morningglory that exhibited climbing growth as well as their final weight. Morningglory that successfully located and climbed structure or green corn weighed more and produced more seed. Ivyleaf morningglory appear to respond to spatial distribution of surrounding objects and possibly used reflectance to preferentially project their stems toward the most prospective structure for climbing.