The spread of morning glory (Ipomoea spp.) in soybean fields in Japan has severely decreased soybean yield. Yet, current control measures do not control the proliferation of Ipomoea spp. As little is known about the flowering period and seed production among the different invading Ipomoea spp., it is challenging to create targeted control measures based on ecological characteristics. This study aimed to reveal the characteristics of the flowering phenology and seed production of four morning glory species, namely, Ipomoea coccinea L. (red morning glory), Ipomoea lacunosa L. (pitted morning glory), Ipomoea hederacea L. Jacq. var. integriuscula A. Gray (entireleaf morning glory), and Ipomoea triloba L. (three-lobe morning glory). Between 2017 and 2019, the four selected study species were grown under similar conditions of soil quality, irrigation, and environmental influences and their flowering phenology and seed data were recorded. The flowering period ranged from 36 to 40 days, and the initial flowering of I. triloba was approximately 2 weeks later than the others. I. coccinea had the highest flowering number and seed production, followed by I. lacunosa, I. triloba, and I. hederacea var. integriuscula. The fruit setting rate of I. triloba decreased later in the reproductive stage but tended to increase as the daily mean temperature increased on each flowering day. Thus, we report that the flowering phenology and seed production differed greatly among the Ipomoea spp. These findings can provide crucial insights into designing targeted species-specific control measures against the spread of Ipomoea spp. in Japan.

中文翻译：

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日本四种牵牛花（Ipomoea）开花物候和种子生产的差异

牵牛花（Ipomoea spp.）在日本大豆田中的蔓延严重降低了大豆产量。然而，目前的控制措施并不能控制番薯属植物的扩散。由于对不同入侵的五爪属植物的开花期和种子产量知之甚少，因此根据生态特征制定有针对性的控制措施具有挑战性。本研究旨在揭示Ipomoea coccinea L.（红色牵牛花）、Ipomoea lacunosa L.（去核牵牛花）和Ipomoea hederacea L. Jacq四种牵牛花的开花物候和种子生产特征。变种。整合肌A. Gray（全叶牵牛花）和Ipomoea triloba L.（三叶牵牛花）。2017 年至 2019 年间，四种选定的研究物种在相似的土壤质量、灌溉和环境影响条件下生长，并记录了它们的开花物候和种子数据。花期36-40天，I.初花。triloba比其他的晚大约 2 周。我。coccinea的开花数和种子产量最高，其次是I。lacunosa , I . 三叶草，还有我。常春藤_整合。坐果率I . 三叶叶在生殖期后期减少，但随着每个开花日日平均温度的升高而增加。因此，我们报告说，番薯属植物的开花物候和种子生产差异很大。这些发现可以为设计针对性的物种特异性控制措施以防止番薯属植物的传播提供重要的见解。在日本。