Sagittaria trifolia is a noxious paddy weed in East Asia. This weed propagates both sexually and asexually. Information on the role of sexual reproduction in the spread of herbicide‐resistant gene(s) and control of S. trifolia is important. Therefore, effects of oxygen, light, and temperature on the germination; germination percentages of fresh and stored seeds; and seed dormancy cycles were clarified. Seeds of S. trifolia require hypoxia and light with temperatures above 30/20°C for germination. Germination percentages increased after 1 month of storage on the soil surface. Germination percentages at 35/25°C for seeds submerged in the summer (simulating a well‐drained paddy during winter) and year round (simulating a poorly drained paddy) for 5 months and exhumed on April 7 were 84.7 and 94.4%, respectively, and decreased gradually to 41.3 and 40.0%, respectively, on June 2 (7 months burial). Germination percentages increased again and reached 63.7 and 94.0%, respectively, on July 25 (9 months burial). Seeds that form in summer germinate quickly at high temperatures, and the seedlings form tubers before winter. Thus, once herbicide‐resistant individuals emerge, the resistant gene or genes is/are easily distributed and fixed in the next generation. Autumn plowing and/or the spraying of herbicides is/are effective for controlling this weed.

中文翻译：

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三叶草的发芽特性

三叶人参是东亚的一种有害稻田杂草。这种杂草在性和无性两方面都传播。关于有性生殖在除草剂抗性基因的传播和黑麦链球菌控制中的作用的信息很重要。因此，氧气，光和温度对发芽的影响；新鲜种子和贮藏种子的发芽率；并阐明了种子休眠周期。三叶草种子需要缺氧和温度超过30/20°C的光线才能发芽。在土壤表面储存1个月后，发芽率增加。在35/25°C下，夏季淹没的种子（模拟冬季排水良好的稻谷）和全年（模拟水稻的排水不良）在5月内发芽的种子的发芽率分别为84.7和94.4％，分别为84.7％和94.4％，并在6月2日（埋葬7个月）分别逐渐降至41.3％和40.0％。7月25日（埋葬9个月），发芽率再次提高，分别达到63.7和94.0％。夏季形成的种子在高温下迅速发芽，而幼苗则在冬季之前形成块茎。因此，一旦出现抗除草剂的个体，抗性基因就可以很容易地分布并固定在下一代中。