In Japan, the spread of morning glory (Ipomoea spp.) in soybean fields has become a serious issue. To establish a control approach for Ipomoea species, this study considered the optimal system combining cultural and chemical control methods. Field experiments were conducted for 3 years to investigate the effects of no-tillage compared with tillage seeding in narrow-row soybean and of application timing of selective post-emergence herbicides bentazone and fluthiacet-methyl. The cumulative emergence of entireleaf morning glory (Ipomoea hederacea [L.] Jacq. var. integriuscula A. Gray) in no-tillage was 25–79% of that in tillage, and the initial growth was suppressed. In no-tillage, the dry matter weight of I. hederacea var. integriuscula was suppressed compared to tillage methods. However, in no-tillage, initial soybean growth was inferior, and reduction of the relative photosynthetic photon flux density (RPPFD) in the soybean canopy was delayed. A combination of selective post-emergence herbicide applications at the second and fourth trifoliate leaf stages (TLS) of soybean was most effective in I. hederacea var. integriuscula suppression. The initial growth of soybean greatly fluctuated yearly, and the period when the RPPFD became less than 50% varied at the fourth through seventh TLS. Therefore, if the initial soybean growth is good, the end of the required period for weed control can be defined as the fourth TLS. No-tillage cultivation combined with management to promote soybean growth, such as adequate soil moisture control by subirrigation systems, may be effective in controlling I. hederacea var. Integriuscula.

中文翻译：

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Ipomoea hederacea var. 的化学和文化控制。日本西南部窄行大豆中的Integriuscula

在日本，牵牛花（Ipomoea spp.）在大豆田中的传播已成为一个严重的问题。为了建立对番薯属物种的控制方法，本研究考虑了结合培养和化学控制方法的最佳系统。进行了为期 3 年的田间试验，以研究免耕与耕作相比在窄行大豆中播种的效果以及选择性芽后除草剂灭草松和氟噻草胺的施用时机。免耕时全叶牵牛花（Ipomoea hederacea [L.] Jacq. var. integriuscula A. Gray）的累计出苗率是耕作时的25%~79%，初期生长受到抑制。免耕条件下，常春藤干物质重量变种 与耕作方法相比，integriuscula受到抑制。然而，在免耕中，大豆的初始生长较差，并且大豆冠层中相对光合光子通量密度 (RPPFD) 的降低被延迟。在大豆的第二和第四三叶阶段 (TLS) 的选择性芽后除草剂应用组合对I. hederacea var.最有效。积分抑制。大豆的初始生长量逐年波动较大，RPPFD 低于 50% 的时期在第 4 至第 7 次 TLS 变化。因此，如果最初的大豆生长良好，则可以将杂草控制所需时期的结束定义为第四个 TLS。免耕栽培与促进大豆生长的管理相结合，例如通过地下灌溉系统控制足够的土壤水分，可能对控制I. hederacea var.有效。Integriuscula。