Abstract
We evaluated the efficacy of herbicide-based control systems against naturalized morning glory species such as three-lobe morning glory (Ipomoea triloba L.) and pitted morning glory (Ipomoea lacunosa L.), in soybean fields. Treatment with whole-surface, leaf-and stem-applied herbicides imazamox ammonium salt solution and bentazone solution were effective against both species from the emergent stage to the 2L stage, and treatment with fluthiacet-methyl emulsion was effective from the emergent stage to the 4L stage. In soybean fields infested with three-lobe morning glory and pitted morning glory, sowing methods and soil-mixed trifluralin emulsion treatments were effective against both species, although there was no difference between one-step sowing with partial shallow tilling and standard two-step sowing methods. However, the number of germinated plants and the residual amounts of both species were reduced to less than half of those in control systems that excluded soil-mixing. In addition, the control systems that included soil-mixed trifluralin emulsion, soil-applied herbicide, and two applications of a foliar herbicide reduced the residual weed volume of these two species of morning glory (three-lobe morning glory and pitted morning glory) by 1-16% compared to treatment with only soil-applied herbicide.
https://ror.org/05qg1fd04 
