Abstract Weed management is essential in vegetable crops, constituting the main production cost. Cultural control strategies can help minimize weed interference and decrease the critical period for weed control (CPWC) when well implemented. Localized nutrient and water supply may favor crop growth, suppressing weeds, and reducing the CPWC. We hypothesized that the drip system reduces the CPWC compared to the micro-sprinkler system and may be recommended as a cultural control method. To support our hypothesis, the objective was to determine the CPWC in onion cultivated under drip or micro-sprinkler during three cropping seasons. Field experiments were conducted during 2016, 2017, and 2018 to evaluate the effects of drip and micro-sprinkler irrigation had on the CPWC in onion (Allium cepa L.). The coexistence of weed in the onion lifecycle significantly reduced the bulb yield for both irrigation systems. The reduction by weed infestation in relative onion bulb yield for the drip system was 61.8, 80.9, and 97.6% in 2016, 2017, and 2018 seasons, respectively. For micro-sprinkler systems, the reduction was 89.2, 85.2, and 98.6% in the 2016, 2017, and 2018 seasons, respectively. The CPWC varied according to the irrigation system and season. For example, in a drip system, the CPWC was 11, 17, and 74 days for 2016, 2017, and 2018. In the micro-sprinkler system, the CPWC was 18, 53, and 45 days in 2016, 2017, and 2018. The predominant weed community determines the irrigation system (drip or micro-sprinkler) that promotes better cultural weed control and reduction of the CPWC in onion cropping systems.

中文翻译：

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灌溉系统能否改变洋葱种植杂草控制的关键时期？

摘要 杂草管理是蔬菜作物中必不可少的，是主要的生产成本。如果实施得当，栽培控制策略可以帮助最大限度地减少杂草干扰并缩短杂草控制关键期 (CPWC)。局部养分和水供应可能有利于作物生长、抑制杂草和减少 CPWC。我们假设滴灌系统与微喷灌系统相比减少了 CPWC，并可能被推荐为一种文化控制方法。为了支持我们的假设，目标是确定在三个种植季节在滴灌或微喷头下种植的洋葱中的 CPWC。2016 年、2017 年和 2018 年进行了田间试验，以评估滴灌和微喷灌对洋葱 (Allium cepa L.) CPWC 的影响。洋葱生命周期中杂草的共存显着降低了两种灌溉系统的鳞茎产量。2016 年、2017 年和 2018 年，滴灌系统的相对洋葱球茎产量因杂草侵扰而减少的分别为 61.8%、80.9% 和 97.6%。对于微喷淋系统，2016 年、2017 年和 2018 年的减少量分别为 89.2%、85.2% 和 98.6%。CPWC 因灌溉系统和季节而异。例如，在滴灌系统中，2016年、2017年和2018年的CPWC为11、17和74天。在微喷头系统中，2016年、2017年和2018年的CPWC为18、53和45天. 主要的杂草群落决定了灌溉系统（滴灌或微喷头），以促进洋葱种植系统中更好的文化杂草控制和减少 CPWC。