Purple nutsedge (Cyperus rotundus L.) is a major weed problem worldwide, particularly in onion (Allium cepa L.) fields in Iran. No specific herbicide has been registered or reported for controlling purple nutsedge in onion fields in the country. To address this, two field experiments were conducted over two years (2021 and 2022) at the Jiroft Culture and Industry Company in Jiroft, Kerman, Iran, using a randomized complete block design (RCBD) with 13 treatments and three replications. The experiments aimed to evaluate the effectiveness of various chemical control methods on onion and purple nutsedge growth.The results indicated that all herbicides significantly reduced the stem number, tuber number, and both aboveground and belowground dry weight of purple nutsedge. The highest level of weed control (100%) was achieved with a combination of Florasulam + Fluazifop P butyl + Pretilachlor and Allyl isothiocyanate, with no phytotoxic effects on onions. The highest onion yields were observed in plots treated with Florasulam + Fluazifop P butyl + Pretilachlor (ranging from 75.047 to 71.856 t ha-1) and Allyl isothiocyanate (ranging from 73.618 to 71.323 t ha-1). Furthermore, purple nutsedge competition reduced onion yield by 88.97% and 90.80% compared to the weed-free control over the two years of the experiment.While Council and Krismat herbicides effectively suppressed purple nutsedge growth, they caused damage to the onion plants. Based on the results, the application of Florasulam + Fluazifop P butyl + Pretilachlor (800 g per hectare) and Allyl isothiocyanate (280 L per hectare) is recommended for controlling purple nutsedge in onion fields. Although Allyl isothiocyanate, as a bio-herbicide, showed promising results similar to the chemical herbicide, Florasulam + Fluazifop P butyl + Pretilachlor is more cost-effective, easier to apply, and safer for users.

中文翻译：

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评估除草剂选择在控制洋葱 （Allium cepa L.） 中紫色坚果 （Cyperus rotundus L.） 的疗效


紫坚果草 （Cyperus rotundus L.） 是世界范围内的主要杂草问题，尤其是在伊朗的洋葱 （Allium cepa L.） 田地。该国尚未注册或报告用于控制洋葱田中的紫色坚果的特定除草剂。为了解决这个问题，在伊朗克尔曼 Jiroft 的 Jiroft Culture and Industry Company 进行了两年内（2021 年和 2022 年）的两次田间实验，使用具有 13 个处理和 3 个重复的随机完全区组设计 （RCBD）。这些实验旨在评估各种化学防治方法对洋葱和紫坚果生长的有效性。结果表明，所有除草剂均显著降低了紫坚果的茎数、块茎数以及地上和地下干重。Florasulam + Fluazifop P 丁基 + Pretilachlor 和异硫氰酸烯丙酯的组合实现了最高水平的杂草控制 （100%），对洋葱没有植物毒性作用。在用 Florasulam + Fluazifop P 丁基 + Pretilachlor（范围从 75.047 到 71.856 t ha-1）和异硫氰酸烯丙酯（范围从 73.618 到 71.323 t ha-1）处理的地块中观察到最高的洋葱产量。此外，在两年的实验中，与无杂草对照相比，紫色坚果竞争使洋葱产量降低了 88.97% 和 90.80%。虽然 Council 和 Krismat 除草剂有效地抑制了紫坚果的生长，但它们对洋葱植物造成了损害。根据结果，建议使用 Florasulam + Fluazifop P 丁基 + 普雷希草胺（每公顷 800 克）和异硫氰酸烯丙酯（每公顷 280 升）来控制洋葱田中的紫色坚果。 尽管异硫氰酸烯丙酯作为一种生物除草剂，显示出与化学除草剂相似的有希望的结果，但 Florasulam + Fluazifop P 丁基 + Pretilachlor 更具成本效益，更易于施用，对用户更安全。